Excitable cells Flashcards

Question

what forms part of the brain stem and also contains the mesencephalon

Answer 1

the midbrain and hindbrain

Answer 2

endoderm- linings of organs mesoderm - bones and muscles ectoderm - nervous system & skin

Answer 3

- derived from the mesoderm & important for signalling

Answer 4

a condition in which the neural tube closes,the anterior pore does not seal and the brain doesnt develop - fatal

Answer 5

it is resultant of failure for the posterior neural tube to close. It typically results in paralysis

Answer 6

4. There are two lateral ventricles located at the top. The third ventricle is located in the centre and the 4th is located at the bottom, near the brainstem

Answer 7

They contain CSF and act to provide nutrients, remove waste and cushion and support the brain

Answer 8

by supplementing diet with folic acid in early pregnancy

Answer 9

anti epilepsy/bipolar drugs interfere with folate metabolism

Answer 10

there are 3 swellings and they become the primary Vesicles within the brain (forebrain,midbrain & hindbrain )

Answer 11

an excess of CSF in the brainstem and can occur due to an injury to another part of the brain

Answer 12

it contains the thalamus (used in sleep, & concious movement) and the hypothalamus (used in homeostasis and reproduction)

Answer 13

complete absence of the cerebellum. Non-fatal, can result in mild cognitive impairment & medium motor problems

Answer 14

a highly developed 6-layer structure of the cortex that mammals have, the number of neurons is related to intelligence

Answer 15

to increase processing power/intellignece as it increases the number of cortical neurons

Answer 16

actions, motor control, speech control and emotion

Answer 17

sensory & language functions

Answer 18

via dorsal roots (afferent neurons)

Answer 19

motor info (efferent neurons)

Answer 20

neural cell bodies butterfly structure

Answer 21

myelinated axons

Answer 22

visual processing

Answer 23

memory as well as sensory and language based info

Answer 24

in the frontal lobe

Answer 25

parietal lobe

Answer 26

we see contralateral motor and sensory pathways : the right side of the brain controls and receives sensory signals from the left side of the body and vice versa

Answer 27

invented silver staining, allowed to see structure of typical neuron due to staining

Answer 28

Principle of dynamic polarisation Principle of connectional specificity

Answer 29

- neurons have preferred transmittance directions

Answer 30

neurons do not make random connections, they contact other neurons and only the specified structures on them

Answer 31

the cells have to be fixed (dead)

Answer 32

- a property in which if a substance has light of particular wavelength shone on it, it emits light of a different wavelength

Answer 33

Prepare selective antibody tagged with fluorescent label Add to tissue and allow to bind strongly Wash off any free labelled antibody Look for where the fluorescence is Image distribution of fluorescence (corresponds to target proteins distribution)

Answer 34

antibodies

Answer 35

you need to have antibodies against proteins that only occur in neurons or whatever you're comparing them to

Answer 36

-focusing a laser at diff levels in a piece of tissue thats been labelled with a fluorescent probe, and look to see where the fluoresces is coming from,

Answer 37

vertebrates

Answer 38

the supporting cells of the nervous system

Answer 39

support the neurons

Answer 40

astrocytes, microglia, oligodendocytes, ependmyial cells

Answer 41

astrocytes

Answer 42

regulate composition of extracellular fluid, important in proliferation & differentiation of neural stem cells

Answer 43

myelinate axons of neurons (oligo's do it to many axons and schwann cells do it to a single axon)

Answer 44

satellite cells and schwann cells

Answer 45

autosomal dominant disorder & caused by abnormallity in huntingtin gene

Answer 46

:Genetically modifying an animal so that its cell produce random combos of up to 4 fluorescent dyes so cells will randomly be one of 100 diff colours.

Answer 47

Amyloid beta plaques and tau clumps (which form neurofibrillarly tangles)

Answer 48

Microtubules. Polymers of tubulin, 20 nm wide. Role: structure and support. Neurofilaments: 10 nm wide: mechanical strength. Microfilaments: actin polymers 5 nm. Tethered to membrane, mediate shape changes.

Answer 49

aberrant movement coordination

Answer 50

a hydration shell

Answer 51

the hydration shell around the ion

Answer 52

charge density , smaller the ion, higher the charge density so larger the shell

Answer 53

Na+ K+ Cl-

Answer 54

Mg2+ and trace metals e.g Fe3+ & Zn2+)

Answer 55

it is both

Answer 56

- the layer of water molecules that immediately contact the ion

Answer 57

larger ions do, they have a smaller hydration shell so have a smaller 'effective' size

Answer 58

primary active transport

Answer 59

the exchange of ions in an opposite direction

Answer 60

an ion aiding in transport of another ion in the same direction

Answer 61

symporter- SGLT (Sodium-glucose linked transporter) Anti-porter- sodium calcium exchanger

Answer 62

ion movement under the influence of an electric field

Answer 63

the electrochemical gradient

Answer 64

Current (I) = Volts (V)/ Resistance(R) Current(I) = Volts (V) x Conductance (1/R)

Answer 65

the direction ions move in is determined by the electrochemical gradient

Answer 66

size of electrochemical gradient nature of ion number of open channels properties of ion channels

Answer 67

only taking specific ions

Answer 68

only taking specific ions

Answer 69

degree to which ions are allowed to flow through

Answer 70

150 outside, 15 inside (10:1 ratio)

Answer 71

5 outside, 100 inside (1:20 ratio)

Answer 72

2 outside, 0.0002 inside (10000:1)

Answer 73

150 outside, 13 inside (11.5:1 ratio)

Answer 74

opposing hard to predict

Answer 75

energy is needed to move ions across the membrane

Answer 76

energy is released when ions move across the membrane

Answer 77

The electrical gradient exactly balances out the chemical gradient

Answer 78

Sodium ions can also cross the membrane and this has consequences for Ek , RMP is more positive than equilibrium potential

Answer 79

RMP is much closer to EK (equilibirum potential for potassium) than ENa (equilibrium potential for sodium)

Answer 80

it is a weighted form of the nernst equation and it allows us to calculate resting membrane potential

Answer 81

The resting membrane potential of neurons is close to EK because the membrane is more permeable to potassium ions than any other ion at rest.

Answer 82

Potassium ions are the primary ion responsible for establishing the resting membrane potential in neurons.

Answer 83

The first ion current to activate during an action potential is the inward sodium current (Na).

Answer 84

The outward potassium current (K) is responsible for repolarization of the neuron during an action potential.

Answer 85

The activation of the **potassium current** . | you just need to know that its a potassium current

Answer 86

in the voltage across the membrane, which cause conformational changes in the channel protein.

Answer 87

in response to changes in the voltage across the membrane, which cause conformational changes in the channel protein.

Answer 88

ensures that only ions with the appropriate charge and size can pass through the channel pore.

Answer 89

tetramers, crystal structure, composed of 4 individual subunits

Answer 90

cytoplasmic segment of the channel protein blocks the channel pore.

Answer 91

ensures that the sodium current is not forever continuous, helps contribute to the rising and falling phases of the action potential.

Answer 92

Fast = occurs rapidly after the channel opens, slow =over a longer period of time, results in a decrease in channel conductance.

Answer 93

period after a fired action potential in which the neuron requires a greater stimulus to create another (the dip)

Answer 94

period during which the neuron can generate another action potential, but only in response to a stronger-than-normal stimulus.

Answer 95

preventing the action potential from re-activating in the region of membrane that has just undergone an action potential. ensures that the action potential can only propagate in one direction, from the initial site of depolarization to the axon terminals

Answer 96

mutations in the SCN1A gene, which encodes the voltage-gated sodium channel **Nav1.1.

Answer 97

Dravet Syndrome, and some forms of focal epilepsy.

Answer 98

due to inactivation of Na current and activation of K current

Answer 99

dendrites (due to current leaking out of the cell membrane)

Answer 100

Rm (inversly proportional to leakiness) Ri( resistance, want as low as possible) And diameter

Answer 101

increasing insulation (increases Rm) having better conductance cores (decreases Ri) having cables with larger diameters

Answer 102

Resistance, capacitance, and inductance.

Answer 103

through the generation and propagation of action potentials.

Answer 104

the distance where the voltage drops to 37% of its original value.

Answer 105

Rm (inversely proportional to leakiness), Ri (resistance, we want as low as possible, lower resistance, higher conductivity) and diameter (want large).

Answer 106

via a wave of action potentials that travel along the length of the axon.

Answer 107

via a wave of action potentials that travel along the length of the axon.

Answer 108

via saltatory conduction, - rapid propagation of action potentials along the myelinated segments of the axon and passive transmission across the non-myelinated segments.

Answer 109

(100-200 Na channels per μm/ 2 per μm)

Answer 110

v high density of sodium channels thought to be where action potential started off in the axons

Answer 111

(higher Rm & a larger diameter, NOT better conducting cores)

Answer 112

Increased axonal diameter no good for animals w/ complex nervous systems - fat heads Myelination

Answer 113

reducing the capacitance and resistance of the axon membrane, decreases the leak of current and increases the thickness of the insulation around the axon.

Answer 114

Conduction velocity increases with axon diameter.

Answer 115

chronic autoimmune disorder characterised by demyelination of CNS neurons caused by an immune attack on oligodendrocytes that provide myelin sheath

Answer 116

estimated 1200 sodium channels /μM,

Answer 117

a wave of action potentials interspersed by segments of rapid cable conduction

Answer 118

MRI scanning Visual evoked potential (VEP) test

Answer 119

disease-modifying therapies (DMTs), Some DMTs are injectable, while others are oral or infused.

Answer 120

Caused by an immune attack on oligodendrocytes that provide myelin sheath insulation that facilitates saltatory conduction

Answer 121

A-alpha fibres

Answer 122

A-Beta fibres

Answer 123

A-delta fibres

Answer 124

Guillain-Barre Syndrome

Answer 125

Action potentials cannot easily jump between neurons due to the synaptic gap.

Answer 126

No, action potentials are not directly transmitted between neurons.

Answer 127

a structural feature of electrical synapses formed by proteins in the membranes of two neurons docking to each other. It is a 3.5 nanonmetre gap

Answer 128

Connexons, made up of 6 connexins

Answer 129

bigger than ion channels, big enough for both ions and small molecules (things up to 1000 molecular weight) to be transported between 2 neurons

Answer 130

Electrical synapses provide a continuous cytoplasmic connection between neurons.

Answer 131

Electrical synapses are fast.

Answer 132

Neurons are connected by gap junctions in electrical synapses, allowing direct ion flow between them.

Answer 133

uncommon, used in systems where you need an escape reflex

Answer 134

need specialised situations, not very flexible & don't have as much plasticity as chemical synapses

Answer 135

Innexins, in the mutant flies, these become disrupted meaning the escape reflex is disabled

Answer 136

through the release of chemical neurotransmitters.

Answer 137

transformed into chemical signals, which bathe the second neuron and excite an electrical signal in the second neuron.

Answer 138

abnormalities or impairments in the communication between neurons at synapses, leading to disruptions in normal neural signalling.

Answer 139

process by which synaptic strength is enhanced, resulting in an increased efficiency of neural communication.

Answer 140

pathological process in which excessive stimulation of neurons, particularly through the activation of glutamate receptors, leads to cellular damage and neuronal death.

Answer 141

term used to describe a group of disorders that arise from dysfunctional ion channels in cells.

Answer 142

Synaptopathy refers to disorders or conditions characterized by impaired synaptic function.

Answer 143

Astrocytes are a type of glial cell in the central nervous system (CNS) that play diverse roles in supporting neuronal function.

Answer 144

It can result from various factors, such as alterations in neurotransmitter release, impaired receptor function, or structural changes in synapses.

Answer 145

It is considered a cellular mechanism underlying learning and memory formation. LTP involves the strengthening of existing synapses or the formation of new synapses.

Answer 146

It can occur in various neurodegenerative diseases and stroke, where excessive glutamate release overwhelms the ability of neurons to maintain ion homeostasis.

Answer 147

abnormalities in the electrical signalling of neurons, muscles, or other tissues, resulting in various clinical manifestations. Examples include cystic fibrosis, long QT syndrome, and epilepsy

Answer 148

Neurotransmission (chemical signaling) is the primary way neurons communicate, providing high flexibility and plasticity.

Answer 149

abnormalities in neurotransmitter release, synaptic connectivity, or synaptic signalling Leads to disrupted neural communication.

Answer 150

Otto Loewi discovered the first neurotransmitter, which is acetylcholine.

Answer 151

autism spectrum disorders, schizophrenia, and Alzheimer's disease.

Answer 152

undergo reactive gliosis - become hypertrophic, proliferate, and release various inflammatory molecules. can contribute to neuroinflammation and tissue damage.

Answer 153

slows it down

Answer 154

resident immune cells of the CNS and act as the primary mediators of immune responses in the brain.

Answer 155

can undergo morphological changes, transitioning from a resting state to an amoeboid/phagocytic state. Become activated & release pro-inflammatory cytokines and can contribute to neuroinflammation.

Answer 156

can be damaged or destroyed, leading to demyelination.

Answer 157

by selectively affecting specific components of the synaptic process.

Answer 158

inflammation that occurs in the central nervous system (CNS) as a response to injury, infection, or disease.

Answer 159

microglia and astrocytes release inflammatory mediators, recruitment of immune cells to the affected area Neuroinflammation can have both protective and detrimental effects on the CNS.

Answer 160

Tetanus/lockjaw and botulism

Answer 161

provide insights into the mechanisms of synaptic transmission and help understand diseases related to synaptic dysfunction.

Answer 162

substances released during neuroinflammation that contribute to the immune response in the CNS.

Answer 163

Neurotransmitter release is Ca2+-dependent, meaning calcium ions trigger the release of neurotransmitter vesicles.

Answer 164

neurotransmitter release occurs in discrete packets called quanta or vesicles.

Answer 165

cytokines, chemokines, prostaglandins, and reactive oxygen species. can influence neuronal function, modulate immune responses, and promote tissue repair or damage.

Answer 166

specialized barrier formed by tight junctions between endothelial cells in brain capillaries.

Answer 167

the integrity can be compromised, allowing immune cells and inflammatory mediators to enter the brain more easily. BBB dysfunction = associated with pathogenesis of several neurological disorders.

Answer 168

regulates the exchange of substances between the bloodstream and the brain, formed by endothelial cells, tight junctions, and specialized transport systems.

Answer 169

it occurs in specific and measurable amounts, corresponding to the release of individual synaptic vesicles.

Answer 170

poses a challenge for delivering drugs to the brain. tight junctions and efflux transporters limit the passage of many therapeutic agents.

Answer 171

Synaptic vesicles are recycled after neurotransmitter release.

Answer 172

Synaptic vesicles undergo endocytosis, where they are retrieved from the plasma membrane and reform inside the neuron.

Answer 173

allows for sustained neurotransmitter release and the replenishment of vesicles for future neuronal signaling.

Answer 174

it allows the infiltration of immune cells, inflammatory mediators, and potentially harmful substances into the brain, contributing to further tissue damage and neurological complications.

Answer 175

cells that can generate or propagate action potentials or electrical impulses

Answer 176

commonly associated with neurons and muscle cells, also exist in plants, bacteria, and single-celled eukaryotes.

Answer 177

guard cells in stomata, which regulate gas exchange, Venus flytrap, which uses electrical signals to trigger its snapping mechanism.

Answer 178

Synaptobrevin -present on the vesicles SNAP25 -present on nerve terminal membrane Syntaxin - present on nerve terminal membrane Synaptotagmin- calcium sensing vesicle protein

Answer 179

involves the action potential activating the calcium channels, many vesicles are releasing their neurotransmitters at once, causing a large response . If dealing with muscle, this is called a **full end plate potential**

Answer 180

release of the neurotransmitters that occurs when there is no action potential and thus no calcium entry the response is much smaller and a smaller size of change in the membrane potential in the postsynaptic neuron, this is a **miniature end plate potential**

Answer 181

Paramecium: - Front end has mechanoreceptors linked to Ca2+ channels. (Activation causes ciliary to beat in reverse direction from stimulus - aka swim backwards) - Back end has mechanoreceptors linked to K+ channels. (Activation leads to faster rate of swimming forwards)

Answer 182

no, spontaneous vesicular release does not require calcium entry or an AP

Answer 183

end plate potential (evoked release) / the size of 1 quantum current

Answer 184

Potassium channels are probably the earliest members of the family, then calcium channels followed by sodium channels.

Answer 185

They move in a wave/whip like co-ordinated fashion. formed from a 9+2 arrangement (9 pairs outside, 2 in middle) of microtubules termed the **axoneme** which is stabilised by protein cross-links via the motor protein dynein.

Answer 186

Deficits in locomotor responses.

Answer 187

Cannot reverse direction - show little or no calcium current (cannot generate action potentials)

Answer 188

Shows an enhanced calcium current - They reverse direction in response to much weaker stimuli than normal cells.

Answer 189

Have reduced voltage gated potassium channel current and show prolonged depolarisation - this means that they swim backwards for much longer than the wild-type. In laymans terms, they have a lower threshold in order to swim backwards thus swim backwards for longer

Answer 190

Protection from damage (predation) Prey capture (venus fly trap) Spreading pollen and seeds

Answer 191

There is some kind of sensory system Fast signal transmission system is present. There is some kind of mechanism to produce movement.

Answer 192

The 'sensitive plant' - It is capable of rapid and co-ordinated movement of its leaves (will curl up in response to touch).

Answer 193

It's leaves will fold up to expose its thorny stems to predators

Answer 194

It is called 'excitation-turgor loss coupling' Which is movement brought about a chloride ion-based action potential which leads to cell shrinkage.

Answer 195

Neurotransmitters influence the conformation (shape) of the receptor they bind to.

Answer 196

Neurotransmitters induce conformational changes in receptors, leading to downstream signaling events.

Answer 197

The stimulus of touch is applied. When the action potential is fired, the rising phase is due to chloride efflux (negative ions leaving the cell) Repolarisation occurs due to potassium efflux. Therefore, there is a net loss of KCl from the cell and water follows out via osmosis - reducing the turgor of the cell.

Answer 198

Ligands are much smaller than receptors, allowing them to bind to specific binding domains.

Answer 199

cys-loop receptors

Answer 200

Increased dendritic spine size Increased number of dendritic spines

Answer 201

at least two

Answer 202

Characterised by the occurrence of epileptic seizures, which are uncontrolled and excessive synchronised electrical activity of central neurons.

Answer 203

Ligands can act as agonists, partial agonists, antagonists, or allosteric modulators.

Answer 204

It is thought to be caused by an imbalance of excitatory and inhibitory circuits: - Glutamatergic neurotransmission is enhanced - GABA release is decreased This leads to an increase in excitatory neurotransmission.

Answer 205

Antagonists block the activation of receptors by preventing neurotransmitter binding.

Answer 206

only produce a partial response, meaning their activity is weaker compared to full agonists. They can both activate and block the receptor, depending on the existing level of receptor activation.

Answer 207

Epilepsy: It reduces the neurotransmitter release at glutamatergic synapses.

Answer 208

bind to the allosteric site, instead of the active site where agonists typically bind. They can enhance or inhibit the receptor's activity, often by modifying the receptor's response to agonists or antagonists.

Answer 209

Epilepsy It increases the amount of inhibitory GABA

Answer 210

The postsynaptic action of a neurotransmitter depends on the specific receptors it binds to.

Answer 211

Yes, the same neurotransmitter can have different effects depending on the receptors present in the postsynaptic membrane.

Answer 212

Epilepsy It prolongs the inactivation of Na+ channels (inhibitory effect - decreases the amount of APs that can be transmitted)

Answer 213

Different receptors can activate different signaling pathways, leading to diverse postsynaptic effects of the same neurotransmitter.

Answer 214

Ion channels (ligand and voltage gated)

Answer 215

metatropic β2-adrenoceptor

Answer 216

Means that cells/neurons are in a depolarised state for longer than usual

Answer 217

It is a mutation in the gene encoding the NR2B, the beta-2 subunit of the NMDA receptor. It can lead to hyperexcitability (GoF) It can lead to hypoexcitability (LoF)

Answer 218

A ligand gated ion channel that binds to glutamate

Answer 219

Gs stimulates Gi - inhibits Gq Gs and Gi operate on adenylate cyclase -Adenylate cyclase converts ATP into AMP Gq operates on IP3 pathway

Answer 220

no, they are trimeric

Answer 221

The condition that causes 'fainting' in goats. It's caused by a mutation in the skeletal muscle chloride channel CLCN1 which causes the goats to have an inability to relax after they have contracted.

Answer 222

transmembrane proteins which bind peptide hormones, growth factors & cytokines, they Phosphorylate target protein tyrosines Example: insulin receptor

Answer 223

Caused by a mutation in the ryanodine receptor (sarcoplasmic reticulum channel) - It involves a state of hyperactivity in muscle cells due to excessive release of calcium from the sarcoplasmic reticulum. - This causes muscles to contract and become rigid which causes a high fever and a very fast heart rate.

Answer 224

Only receptor type that is intracellular Effects tend to be slower than other receptor types hours to days Examples: oestrogen, progesterone & glucocorticoid

Answer 225

Causes rhabdomyolysis (muscle breakdown) Very high blood potassium levels (potentially fatal)

Answer 226

Bind to lipid soluble ligands e.g. steroids Increase/decrease transcription of specific genes

Answer 227

Structural Metabolic sensing Repair Modulation of synapse transmission

Answer 228

The atrophy and functional asthenia (lack of energy or strength) which is neurotoxic and decreases their abilities. - Occurs in Alzheimer's/Huntington's

Answer 229

Nurturer Sentinel Warrior

Answer 230

GABAa 5HT3 receptor Inhibitory glycine receptor nAChR

Answer 231

Synaptic remodelling and migration Removal of apoptotic neurons They are evenly spaced out

Answer 232

no, but function similarly

Answer 233

Surveillance and sensing They have lots of processes and are in motion.

Answer 234

Defence against infectious pathogens and injurious-self proteins. They are stocky and accumulate.

Answer 235

close channel if ligand binds for too long

Answer 236

nAChR, 5 subunits

Answer 237

amino acids, - L glutamate, glycine & aminobutyric acid (mono) amines, anything ending in amine (dopamine, histamine), (nore)epinephrine, serotonin (ACh is an amine not a monoamine) and peptides. endorphins, vasopressin, oxytocin

Answer 238

A neuron only releases one type of neurotransmitter (he never said this, but was the interpretation) THIS IS NOT TRUE

Answer 239

Neurons that release multiple neurotransmitters are called co-transmitters.

Answer 240

allows for complex and diverse signaling within the nervous system.

Answer 241

The two main types of neurotransmitter receptors are ionotropic and metabotropic.

Answer 242

Ionotropic receptors directly open ion channels upon neurotransmitter binding, leading to rapid synaptic transmission.

Answer 243

activate signaling pathways through G proteins, which ultimately lead to cellular responses.

Answer 244

In these diseases the respective proteins are produced. This causes the microglia to change in response to the pathology (turn to warrior state) in attempts to clear the disease stimulus. However, the stimuli inhibit it's ability to do this which leads to exaggerated proinflammatory response. Therefore neurotoxicity and neurodegeneration.

Answer 245

Multiple sclerosis (demyelination of axons)

Answer 246

It is a pathology that occurs due to the demyelination of neurons and it characterised by: - Limb numbness/weakness - Vision problems - Fatigue/dizziness - Tremor

Answer 247

Invading immune cells: - Encephalitis - Multiple sclerosis

Answer 248

CNS-resident cells

Answer 249

It is an inflammatory response in the central nervous system. Immune cells cross the blood brain barrier and infiltrate nervous tissues - activating microglial cells. this process induced modification in neuronal and synaptic environment which increases the concentration of pro-inflammatory cytokines and reactive oxygen species (ROS). This can lead to significant damage to cell structures known as oxidative stress.

Answer 250

It is the continuous endothelial membrane of the brain vasculature. It restricts the movement of solutes and the migration of cells and pathogens into the brain.

Answer 251

(From inside to out) - endothelial cells (with tight junctions) - pericyte - basement membrane - astroglial 'foot'

Answer 252

Healthy blood vessels Adequate blood flow Recruitment of active transport systems

Answer 253

nicotinic - Excitatory Fast responses µs-ms Muscarinic - Excitatory or inhibitory dependant on subtype Slow responses ms-s

Answer 254

In Parkinson's, there is a lack of dopamine. Dopamine cannot cross the BBB. L-DOPA, a precursor to dopamine can cross the BBB via CMT (carrier mediated transport) Therefore L-DOPA is used instead of dopamine as a treatment.

Answer 255

AMPA () Kainate NMDA

Answer 256

Highly permeable to Ca2+ Blocked by Mg2+ at RMP Need glycine (or D-serine) as a co-agonist 4 subunits, need 2 glutamate and 2 glycine to bind to open

Answer 257

Increased vascular permeability Toxic blood-derived molecules, cells and microbial agents enter the brain. Inflammatory and immune responses. Neuronal injury, synaptic dysfunction, loss of neurons, loss of brain connectivity Neurodegeneration.

Answer 258

Physiological Cellular Association with disease.

Answer 259

ionotropic (ligand gated ion channels) , metabotropic (family C GCPRs)

Answer 260

○ Sleep/wake ○ Body temperature ○ Cardiac output ○ Memory ○ Energy metabolism ○ Eating behaviour ○ Immune response Detoxification

Answer 261

○ Cell cycle progression ○ DNA damage repair ○ Cellular energy metabolism ○ Cell detoxification Neuronal excitability.

Answer 262

Receptors for neurotransmitter released by the nerve terminal in the membrane they reside in, regulate the release of that neurotransmitter Usually inhibitor (negative feedback) Alpha type 2 adrenoceptors which regulate noradrenaline release from cardac sympathetic neurons

Answer 263

○ Affective disorders (Bipolar, depression) ○ Sleep disorders ○ Neurodegenerative disease (Alzheimer's) ○ Obesity/metabolic syndrome Inflammation (Asthma, COPD)

Answer 264

Cellular rhythms lead to physiological rhythms which will in turn impact diseases associated with rhythms

Answer 265

Responds to a diff neurotransmitter than that released by the neuron its embedded in presynaptic nAChR’s - acetylcholine regulates dopamine release in the striatum

Answer 266

Chronic shift work Sleep deprivation Altered eating habits Jet lag

Answer 267

a high conc of dopaminergic synapses

Answer 268

Ultradian Circadian Infradian Circannual

Answer 269

member of Ly6 superfamily, is a protein that interacts with nAChRs to change their protein (important in regulating regulatory systems)

Answer 270

Annual/seasonal

Answer 271

Alpha-bungarotoxin = a peptide toxin that targets the skeletal muscle nAChR Alpha-neurotoxins - usually target nicotinic acetylcholine receptors Alpha-conotoxins are a group of small peptide toxins from marine snails

Answer 272

through various mechanisms, including receptor binding, modulation of ion channels, and second messenger systems.

Answer 273

It is a self-sustained oscillator Has a period of ~24 hours Entrained by the environment (mostly by light) Rhythmical outputs are on a cellular to physiological level.

Answer 274

Mechanisms such as reuptake, enzymatic degradation, and diffusion help remove neurotransmitters from the synaptic cleft.

Answer 275

Mechanisms such as reuptake, enzymatic degradation, and diffusion help remove neurotransmitters from the synaptic cleft.

Answer 276

Acetylcholine is degraded by the enzyme acetylcholinesterase in the synaptic cleft

Answer 277

Acetylcholine is degraded by the enzyme acetylcholinesterase in the synaptic cleft

Answer 278

suprachiasmatic nucleus (regulates biological rhythms)

Answer 279

GABA (gamma-aminobutyric acid) is the main inhibitory neurotransmitter in the brain.

Answer 280

In the hypothalamus, a pair of nuclei next to each other with roughly 10,000 neurons each.

Answer 281

Glutamate receptors mediate excitatory neurotransmission in the brain and are important for synaptic plasticity and learning.

Answer 282

It is the retinohypothalamic tract and it connects the hypothalamus to the retina

Answer 283

Short-term synaptic modification can occur through processes like synaptic potentiation or depression.

Answer 284

Long-term synaptic modification involves structural and functional changes in the synapse, including synaptic plasticity and long-term potentiation (LTP) or long-term depression (LTD).

Answer 285

Postsynaptic potentials are graded, meaning their amplitude can vary depending on the strength of the input.

Answer 286

region of a neuron where the axon originates from the cell body.

Answer 287

Inputs from multiple synapses are summed at the axon hillock, and if the threshold is reached, an action potential is generated.

Answer 288

through the pattern and frequency of action potentials generated by neurons.

Answer 289

changes in the firing rate of action potentials to convey different aspects of information.

Answer 290

Different frequencies of action potentials can represent different stimulus intensities or encode specific features of sensory input.

Answer 291

The retinohypothalamic tract (RHT) and it's processed in the core SCN

Answer 292

Travels via the RHT to the core SCN where it will process this information and adjust the circadian rhythms accordingly Then passing information to the shell SCN. The shell SCN will then send projections to other parts of the brain, that sends connections to the organs they're associated with, causing the organism to be in synchronisation

Answer 293

Multiple PSP’s from a single synapse , how often do they occur

Answer 294

Post synaptic potentials (PSP) form multiple synapses effect summation of a neuron How close/far to hillock/initial segment

Answer 295

Dendrites behave like cables PSPs travel from dendrites to hillock/initial segment passively & attenuate By the time we get to the hillock, we have severe attenuation

Answer 296

an inhibitory synpase being located closer to the axon hillock than an excitatory synapse, causing the inhibition of an excitatory response

Answer 297

frequency modulation - constant amplitude but changes frequency that the signal is sent

Answer 298

Inside cells there is a molecular clock comprised of genes called clock genes. These genes are expressed in a rhythmic fashion which ultimately generates circadian rhythms in neuronal function

Answer 299

Neuronal firing Neuropeptide secretion Behavioural state Gene expression

Answer 300

Melatonin is secreted by the pineal gland

Answer 301

During sleep/pre-sleep when there is no/less light

Answer 302

Pineal gland.

Answer 303

In almost every single cell in our body.

Answer 304

It is the study of the manner and extent to which the kinetics and dynamics of medication are affected by the endogenous biological rhythms. and... How the dosing time of medications affects biological timekeeping and features of biological rhythms.

Answer 305

They coincide and it is in relation to chronotherapy.

Answer 306

It is the first anticancer drug to undergo chronotherapeutic development. A study found that when it was tested as a chronodrug as apposed to a constant rate drug: - the mean dose of oxaliplatin and its maximum tolerated dose could be increased by 15% if given in a circadian rhythm-modulated rate.

Answer 307

It is a first line treatment for bipolar disorder which causes period lengthening and phase delay of the sleep-wake and body temperature rhythm

Answer 308

Seasonal affective disorders Unipolar and bipolar depression (and other forms of depression) benefits: - Improved mood - Enhanced sleep efficiency

Answer 309

It is a basic homeostatic need which is important for learning, memory, growth and repair.

Answer 310

Cognitive impairment Performance impairment Immune system impairments

Answer 311

REM: rapid eye movement NREM: non-rapid eye movement

Answer 312

NREM (light sleep) 1-7mins length 5% total sleep time

Answer 313

NREM (deeper sleep) 10-25 min length 45% of total sleep time.

Answer 314

NREM (deepest sleep) 20-40 mins 25% of total sleep time

Answer 315

REM (dreaming) 10-60 mins 25% of total sleep

Answer 316

Ventrolateral preoptic and sleep

Answer 317

Lateral hypothalamic area (LHA) LDT PPT Raphe LC

Answer 318

SCN SPZ DMH

Answer 319

It is a model that outlines the relationship between Orexin, the vlpo (sleep) and the LC, Raphe (and other awake areas of the brain) - The activation of one state will inhibit the other. - Parts of the brain that are involved with staying awake will inhibit the sleep areas (and vice versa). - Regulated by orexin.

Answer 320

The interaction between the homeostatic drive to sleep and circadian rhythm alerting signal.

Answer 321

The sleep drive increases from 7am and peaks at 11pm - steeply dropping until 7am. The drive for arousal forms a 'mound shape' steeply dropping off at around 10-11pm. This means that as arousal drops, the sleep drive (melatonin production) increases. Where the arousal drive drops and the sleep drive peaks sleep commences

Answer 322

Light Jet lag/shift work Pain/stress/medical conditions Medication/other substances Sleep environment

Answer 323

A chronic sleep disorder in which sufferers suffer from profound daytime sleepiness.

Answer 324

It is caused by disruptions to the brains orexins pathways which is thought to be an autoimmune attack on orexin producing neurons

Answer 325

It is a neuropeptide produced by a small number of neurons in the hypothalamus. It acts on a g protein coupled receptor called Hcrtr2

Answer 326

decussating

Answer 327

greatest when the molecule can only move in one dimension

Answer 328

Opening of sodium channels

Answer 329

depolarize the equilibrium potential for potassium becomes more positive so resting membrane potential will in turn become more positive

Answer 330

GABAA receptor

Answer 331

Alzheimer’s disease (hyper phosphorylated tau neurofibrillary tangles)

Answer 332

Omega-conotoxin

Answer 333

GABAA receptor (Glycine receptor, part of same superfamily as GABAA)

Answer 334

GABAA receptor (Glycine receptor, part of same su;erfamily as GABAA)

Answer 335

green algae

Answer 336

ganglion cell

Answer 337

cell bodies of bipolar cells, cell bodies of amacrine cells & horizontal cells

Answer 338

rods and cones

Answer 339

Conotoxins

Answer 340

Retinal ganglion cells

Answer 341

1. Move electrode onto cell 2. Form a seal on the cell surface. 3. Pull electrode away from cell 4. Move electrode out of the bath solution

Answer 342

IP3 via Gq

Answer 343

G Protein Coupled Receptors

Answer 344

corticosteroids

Answer 345

troponin must bind calcium

Answer 346

drooping eyelids

Answer 347

thick filaments

Answer 348

AMPA and NMDA receptors

Answer 349

calcium channels

Answer 350

chloride efflux or potassium influx

Answer 351

halorhodopsin

Answer 352

phosphodiesterase is activated; sodium channels close

Answer 353

ryanodine receptor

Answer 354

Brain surgery Cranial trepanation Experimental ablation

Answer 355

Cranial trepanation: - drilling/cutting holes in the skull in aims to heal or be part of a ritual - dates back to 7000 years ago. Experimental ablation: - Consists of lesioning or destroying a specific part of the brain to study its function

Answer 356

A map of the regions of the brain so that surgeons can locate the exact region for treatment/lesioning.

Answer 357

Electrode Cannula

Answer 358

Stainless steel electrode with a conducting element will heat up and destroy nearby cells. Not very specific lesioning.

Answer 359

It is the use of excitatory aminoacids which are injected into a specific area via a cannula. It is more specific lesioning as they stimulate more specific neurons to death - creating the lesion.

Answer 360

A placebo procedure that duplicates all the steps of producing a brain lesion except for the one that actually causes the brain damage

Answer 361

Refer to a group of procedures (including fixing, slicing, staining and examining the brain) that aim to observe the location of the the lesion

Answer 362

Railroad construction foreman in the US. Injured by taking an iron rod straight through his head. This changed him: - Couldn't stick to a plan - became rude, violent and uncontrollable. First case to suggest a link between brain trauma and personality change.

Answer 363

measures the electrical activity of neurons by detecting the changes in voltage or current outside the cells.

Answer 364

Used electrical brain stimulation on awake patients for the treatment of epilepsy. He recorded patient's reaction when stimulating certain brain areas. Used this information to create a functional map of the cortex and brain. - He created the 'motor homunculus' as a result of this work

Answer 365

single-unit recording, multi-unit recording, and field potential recording

Answer 366

Electrophysiology (single/multiple cell recording) Electroencephalography (EEG) Deep brain stimulation

Answer 367

Involves implanting electrodes within certain areas of the brain, the level of stimulation is controlled by a pacemaker like device planted under the skin of your upper chest.

Answer 368

Regulate abnormal impulses. Affect certain cells and chemicals within the brain. Approved to treat: - Parkinson's - Obsessive compulsive disorder - Epilepsy

Answer 369

It is an imaging technique that combines a series of x ray images taken from different angles and uses computer processing to create cross-sectional images.

Answer 370

Pinpoint the location of a tumour Guide procedures such as surgery/biopsy Detect and monitor disease such as cancer. Monitor treatment effectiveness.

Answer 371

extracellular recording - easy not specific intracellular recording - hard, specific Patch-clamp recording - Very hard , very specific

Answer 372

It is a scan that uses a radioactive drug (tracer) to show brain activity. The tracer is applied which then collects in areas of your body in which there are higher levels of chemical activity.

Answer 373

It uses a magnetic field and radio waves to create detailed images of the brain. It is the most frequently used imaging test of the brain and spinal cord.

Answer 374

○ Aneurysms. ○ Disorders of the eye and inner ear. ○ Multiple sclerosis. ○ Spinal cord injuries. ○ Stroke. ○ Tumours. ○ Brain injury from trauma.

Answer 375

functional Magnetic Resonance Imaging. It measures the metabolic changes within the brain.

Answer 376

Can be used to examine brain anatomy in people being considered for brain surgery and it can also be used to assess damage from a head injury or from disorders such as AD

Answer 377

It involves the altering the genes inside your body's cells to treat or stop disease, instead of using drugs or surgery.

Answer 378

Large cells (50ml to metered or larger)

Answer 379

Replacing a mutated gene that causes disease with a healthy copy of the gene. Inactivating, or 'knocking out', a mutated gene that is functioning improperly. Introducing a new gene into the body to help fight a disease.

Answer 380

Ex vivo gene transfer (insertion of genetically modified cells) Direct in vivo injection of viral vectors into the target tissue

Answer 381

Sakmann & Neher in the late 1970’s Not a single method, collection of 4-5 diff configurations

Answer 382

Retroviral and lentiviral Adenovirus and adeno-associated virus Herpes simplex virus

Answer 383

Glass tube placed in a heating element, glass softens when heated, pulling electrode apart End up w/ thin walled glass spike which needs to be sealed onto surface of cell Take thick sticky resin and tape to end of electrode, dip fine wire into resin solution Once successfully coated, heat resin and rest to use Take electrode & put close to a heat source to smooth edges of glass Use positron electrode on cell

Answer 384

Glass tube placed in a heating element, glass softens when heated, pulling electrode apart End up w/ thin walled glass spike which needs to be sealed onto surface of cell Take thick sticky resin and tape to end of electrode, dip fine wire into resin solution Once successfully coated, heat resin and rest to use Take electrode & put close to a heat source to smooth edges of glass Use positron electrode on cell

Answer 385

New gene is inserted into a vector Vector is injected and enters target cell New gene is delivered into the nucleus. (detailed version:) - New gene inserted into vector which is then injected. - When it comes into contact with the target cell it will enter through the membrane where it is packaged into a vesicle. - The increasing acidity causes the release of pentons, and their toxicity breaches the vesicle. - The virus will then enter the nucleus and disassemble to deliver the DNA into the nucleus. - Genetic information from the new gene is transferred to mRNA which is now the blueprint for the production of the desired protein.

Answer 386

Record currents through a limited number of active channels at cell surface Take electrode, manoeuvre to surface of cell, apply gentle suction Form tight seal between electrode and membrane Trap channels under puppets to measure activity

Answer 387

They provide new cells for the body as it grows, and replace specialised cells that are damaged or lost. There are three main types: - Embryonic stem cells - Adult stem cells - Induced pluripotent stem cells.

Answer 388

Record currents through active channels in a whole cell- good at seeing cell current responses to drugs Manoeuvre electrode to surface of cell, apply **further** suction Form tight seal between electrode & glass Trap channels Under pipette Disrupt membrane trapped under electrode

Answer 389

Self-renewing population that generates neurons and glia of the developing brain. They can be isolated, proliferated, genetically manipulated and differentiated in vitro and reintroduced into a developing adult or a pathologically altered CNS.

Answer 390

Whole cell recording

Answer 391

Perforated patch Instead of applying further suction, add antibiotic to make perforation in membrane

Answer 392

Declarative (explicit) - Results from conscious effort Non-Declarative (implicit) - Results from direct experience.

Answer 393

Declarative: - facts - events Non-declarative: - procedural skills/habits - associative memories

Answer 394

Record currents through a single active channel away from a cell - good for looking at agents that **modulate channel by working at its intracellular face** Start with the same process as cell attached Trap Channels under electrode , form seal, ** pull membrane away** Take electrode ** out of bath** Put electrode **back into bath**

Answer 395

Hippocampus: Involved in explicit memory Cerebellum and basal ganglia: procedural memory Amygdala: emotional responses Many regions of the cortex: Short and long term explicit memory.

Answer 396

Not very versatile, hard to make a change in this state, hard to set up

Answer 397

Hippocampal neurons that fire at a high rate whenever the animal is in a specific location in the environment - called the place field.

Answer 398

Record currents through a single active channel away from cell - good for looking at ** agents that modulate channel by working at its extra cellular face** Start with cell attatched —> whole cell recording Rip a bit of the membrane off but ** KEEP IT IN THE BATH**

Answer 399

Internal neural representations of the landscape in which an animal travels.

Answer 400

Open state - determined by K+1(opening rate constant) Closed state - determined by K-1 (closing rate constant)

Answer 401

London taxi drivers have greater grey matter in the hippocampus than bus drivers. - The difference is that taxi drivers have to navigate new routes. This suggests that spatial knowledge is associated with the pattern of hippocampal grey matter volume.

Answer 402

Because rate constants determine probability, but it’s still random

Answer 403

Last for seconds to hours. Repetition promotes retention Limited capacity 'labile' - sensitive to disruption Does not require new RNA or protein synthesis.

Answer 404

1/ rate constant

Answer 405

activation mechanisms

Answer 406

Used to hold information 'in mind' A limited storage store that needs repetition to keep it in mind. It is the maintenance and manipulation of memory.

Answer 407

Ion conc Voltage across membrane Pore properties

Answer 408

Lasts for days to years. Unlimited capacity Consolidated (insensitive to disruption) Does require new RNA or protein synthesis

Answer 409

Sensory stimulus: - Brain receives information Encoding: - Brain transduces and stores information Storage: - Brain retains information Retrieval: - Brain retrieves information in order to utilise it.

Answer 410

There would be at least three different levels of current. Think of it like stairs, if there are at least 3 levels of current , there have to be at least 3 stairs in the staircase. You can’t have a staircase with 3 different heights but only 2 stairs.

Answer 411

Hebbian plasticity - Neurons that fire together work together. "When an axon of cell A is near enough to excite cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as one of the cells firing B, is increased" (Hebb, 1949)

Answer 412

It is a conventional electrophysiological technique used to artificially control the membrane potential (V m) of large cells to study the properties of electrogenic membrane proteins, especially ion channels. A common method for expressing proteins of interest is to inject mRNA coding for the protein into the **oocytes of the Xenopus Laevis**

Answer 413

Long term potentiation. It is a persistent strengthening of synapses following high frequency stimulation of chemical synapses. It produces a long-lasting increase in signal transmission between two neurons.

Answer 414

LTP and LTD

Answer 415

RNA is very labile, need to be careful not to degrade it

Answer 416

Xenopus laevis oocytes TEVC = Xenopus oocytes, THIS IS ALL YOU NEED TO REMEMBER

Answer 417

Slices of the hippocampus are used. Brief bursts of high frequency stimulation (tetanus) is applied to the CA1 region of the hippocampus. As a result LTP was induced and the synapses had stronger electrical responses.

Answer 418

AMPA and NMDA receptors

Answer 419

A calcium binding dye that when it binds to calcium, changes it’s absorption spectrum

Answer 420

A glutamate ligand gated ion channel that results in the influx of Na+ into the cell.

Answer 421

Local - limited to what we can patch onto Global (whole neuron, circuit) a don’t have info on what’s going on between local & global level

Answer 422

4 carboxylic acid groups Polar substance - can’t cross cell membranes

Answer 423

They are glutamate ligand gated ion channels. Require glutamate, glycine and depolarise to open which allows the influx of Na+ and Ca2+. (extra info) The increase in Ca2+ in the post-synaptic neuron can then act as a second-messenger to activate intracellular signalling cascades. - only occurs when the magnesium block in removed via depolarisation

Answer 424

Presynaptic: - Increased neurotransmitter vesicles - Increased neurotransmitter release Postsynaptic: - Increased dendritic area and spines (increased sensitivity) - Increase AMPA receptors

Answer 425

Absorption spectra- goes from 380nm - 340 nm with a BIGGER PEAK, shift allows us to measure conc of calcium Emission spectra- stays at 510nm but PEAK BECOMES BIGGER

Answer 426

Changes in size: - Increase in number of neurotransmitter receptors - Increase in presynaptic vesicles - Increase in postsynaptic vesicles Multiple spine boutons: - Formation of another spine will double the receptors Both of these are key in LTP as they help to strengthen and increase the electrical activity of these synapses

Answer 427

Proteins Genetically encoded Ca2+ indicators GCaMP (calmodulin & M13)

Answer 428

Long Term Depression: It is the long lasting decrease of efficiency of synaptic transmission (especially with AMPA receptors)

Answer 429

The insertion of an indicator into an animal genome to target a particular cell or tissue Drosophila set up

Answer 430

Two excited fluorophores (one acceptor & one donor) that emit different wavelengths Close proximity of fluorophores

Answer 431

It is caused synaptic transmission occurring as the same time as a weak or modest depolarisation of the postsynaptic neuron. It strengthens the robustness of stored experience by pruning away synapses that are weakly integrated into a synaptic network that stores a specific experience

Answer 432

Halobacterium (arahchaebacterium)

Answer 433

Yellow or Orange light

Answer 434

A strong depolarisation will lead to high levels of Ca2+ and therefore LTP A weak depolarisation will lead to little Ca2+ influx and therefore LTD

Answer 435

Blue light

Answer 436

Chloride influx

Answer 437

(results from experiments in mice) - Hippocampus-dependent learning and memory - Fear conditioning in the amygala. - Recognition memory in perirhinal cortex - Cerebellar learning

Answer 438

Cyclic GMP pathway via transducin

Answer 439

Psychiatric disorders (e.g., depression, schizophrenia) Drug addiction Mental retardation Neurodegenerative diseases (Alzheimer's disease)

Answer 440

Make radiolabeled version of a ligand that binds to protein of interest Mix with tissue of interest measure how much radioactivity has bound to tissue

Answer 441

Make radiolabeled version of a ligand that binds to protein of interest Mix with tissue of interest measure how much radioactivity has bound to tissue

Answer 442

Retrograde: - difficulty remembering past information Anterograde: - difficulty in learning new information

Answer 443

Measuring amount of binding at diff conc Screen of new drugs (compare radioligand to competing non-radioactive ligand/drug)

Answer 444

Measuring amount of binding at diff conc Screen of new drugs (compare radioligand to competing non-radioactive ligand/drug)

Answer 445

Easy to set up Cheap Easily scaled

Answer 446

Doesn’t tell us what drug does at receptor Doesn’t have good time resolution Uses hazardous materials & produces hazardous waste

Answer 447

He had a bilateral medial temporal lobe resection that lead to to anterograde amnesia. (He had his hippocampus removed which lead to an inability to form new memories)

Answer 448

Diopters (D’s) Lens = 12d’s Cornea = 42 D’s (around 3x)

Answer 449

Fluid that allows light through but keeps eye structure, apply pressure to keep retina in right place

Answer 450

Short sightedness Concave lens

Answer 451

it is a general term used to describe a group of conditions that affect memory. More than 850,000 people in the UK diagnosed with dementia. The two main types: - Alzheimer's - Vascular dementia

Answer 452

Longsightedness Convex lens

Answer 453

Rods are more long and cylindrical, cones Are rounded

Answer 454

Horizontal and amacrine cells

Answer 455

It is characterised by the presence of intracellular neurofibrillary tangles (tau protein) and the accumulation of extracellular beta-amyloid plaques. It leads to memory loss and a continuous decline in thinking, behavioural and social skills.

Answer 456

GCPR’s with 7 transmembrane domains

Answer 457

Can be developed after a stroke or it can result from other conditions that damage blood vessels and reduce circulation. Symptoms vary, depending on the part of the brain affected, but can include problems with memory, reasoning, planning or judgement.

Answer 458

It is a sea snail that has been used to understand the link between cellular mechanisms behind memory, learning and behaviour.

Answer 459

Causes enzymatic degradation of cyclic GMP into GMP, meaning no cGMP to activate sodium channel so no depolarisation

Answer 460

Parapodium Mantle shelf Siphon Gill

Answer 461

When 11-cos retinal absorbs a. Photon of light Leads to A conformational change in the rhodopsin

Answer 462

it's withdrawal reflex. When a tactile stimulus touches/brushes past the siphon or the mantle shelf, the siphon and gill with retract and the parapodium will cover them to protect them

Answer 463

(In this order) Transducin activation Conversion of GDP to GTP Release of phosphodiesterase Reduced cGMP Closure of sodium channels

Answer 464

Red and green opsins both on X chromosome, men only have one X chromosome

Answer 465

Habituation: - loss of response due to repeated stimulus. Dishabituation: - recovery of an innate response (after habituation) Sensitisation: - response stronger than normal (becoming more sensitive to a stimulus

Answer 466

Amacrine cells

Answer 467

On and off

Answer 468

Does not cross optic chiasma and goes to same side of brain

Answer 469

Retinal ganglion cells

Answer 470

Melanopsin

Answer 471

The periphery of the olfactory system

Answer 472

The movement of the gill was recorded to trace the amplitude and response to a specific stimulus. The researchers would then poke the siphon at different rates to measure the learning. Results: - habituation occurred when there was no negative stimulus after the poke. - dishabituation occurred when there was a shock to the tail after being poked. This shows classical conditioning

Answer 473

Reflex = unconditioned response tactile stimulus to tail: conditioned stimulus shock: unconditioned stimulus. It was found that when the tactile stimulus was paired with the shock that it brought about a much larger response than if it wasn't

Answer 474

GDP-GTP exchange Activates adenylste Cyclase Breaks down ATP into cAMP cAMP released & opens gated channels Calcium & sodium influx Depolarisation

Answer 475

Ability to encode intensity and diversity of many diff odorants

Answer 476

Each odorant binds to various receptors and activates many neurons

Answer 477

Circumvallate (back) Foliate (sides) Fungiform (front)

Answer 478

Taste buds

Answer 479

Over the days of the experiment of the tactile stimulus being applied, the response decreased showing that long term memory has occurred. may falter after long periods but the response will still be lower than original value before learningn

Answer 480

Proboscis, legs & wing margins

Answer 481

GCPRS T1R1 & T1R3 for umami T1R2 and T1R3 for sweet T2R for bitter

Answer 482

TRP channels

Answer 483

After a period of training (4 days) the aplysia with the tactile stimulus and the shock the response stayed above the original response for up to 26 days. (the response did decrease over time but it was still above the baseline before learning)

Answer 484

In humans, unknown In mice - epithelial Na Channel

Answer 485

Synaptic Biophysical Molecular

Answer 486

Vomeronasal organ

Answer 487

Scale vestibuli Tympani Scalia media

Answer 488

Semicircular canal Otolith organs (utricle & saccule) Hair cells

Answer 489

Structure of the cochlea

Answer 490

Direct form of transduction that occurs very quickly due to no electrical component being required

Answer 491

Vision (Na+)

Answer 492

Sensitisation to the input (tail shock) causes spike broadening, leading to an increased duration of the AP on the sensory neuron leading to more neurotransmitter release and an increased excitatory postsynaptic potentials.

Answer 493

Skeletal, cardiac, smooth

Answer 494

Movement, heat generation

Answer 495

Endomysium

Answer 496

Sarcolemma

Answer 497

Outside protective sheath that covers the endomysium in skeletal muscle

Answer 498

Serotonin acts on the sensory neuron causing increased sensory neuron excitability, increased motor neuron excitatory post synaptic potentials and therefore a higher reflex amplitude (which is what characterises sensitisation).

Answer 499

Bundles of filaments called myofibrils Myofibrils composed of filaments called myofilaments T-tubules that lean from sarcolemma into interior of skin Plasma membrane - sarcolemma Endoplasmic reticulum (sarcoplasmic reticulum) wrapped around myofibrils

Answer 500

Terminal cisterns interacting with t-tubules

Answer 501

Cardiac and skeletal

Answer 502

1. Serotonin temporarily closes potassium channel (S current) in sensory neuron. 2. Outward potassium current is slowed. 3. Repolarisation of membrane potential is slowed -> spike broadening 4. Increase calcium influx. 5. Increase in transmitter release. 6. Enhanced excitability

Answer 503

Repeated myofibrils unit Thick filaments - composed of myosin and titin Thin filaments - composed of actin and nebulin

Answer 504

Repeated myofibrils unit Thick filaments - composed of myosin and titin Thin filaments - composed of actin and nebulin

Answer 505

Titin (3rd most abundant too)

Answer 506

Thick filaments only

Answer 507

Thin filaments only

Answer 508

The overlap of thick and thin filaments

Answer 509

When there is optimal overlap between actin and myosin

Answer 510

Hexameric Formed of two heavy chains and 4 light chains

Answer 511

Regulatory and essential

Answer 512

9 8 in skeletal and cardiac muscle 1 in smooth

Answer 513

Built in ATPase activity

Answer 514

Globular - g actin Filamental - f actin (the one found in muscle)

Answer 515

Serotonin binding to the sensory neuron increases the levels of cAMP. cAMP acts as a secondary messenger, activating PKA in the cytoplasm of the cell. PKA's actions lead to spike broadening and enhanced excitability (sensitisation)

Answer 516

One tropomyosin per 7 actin monomers

Answer 517

One tropomyosin per 7 actin monomers

Answer 518

Trimeric complex associated with tropomyosin and actin Troponin T- associates with tropomyosin Troponin I - associates with Actin, inhibits formation of cross bridges Troponin C- binds calcium

Answer 519

1.Repeated serotonin or cAMP applications 2. Persistent phosphorylation of preexisting proteins and synthesis of new proteins. 3. Long-term increase in synaptic facilitation 4. Long-term increase in synaptic transmission 5. Dramatic growth of sensory neuron processes. 6. LONG-TERM MEMORY FOR SENSITISTION

Answer 520

Habituation will decrease boutons Sensitisation will increase boutons

Excitable cells Flashcards

(583 cards)