Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

From Flashcardlet > Bio 2: Exam 3 > Flashcards

Bio 2: Exam 3 Flashcards

(91 cards)

Start Studying
0
Q

What provides much of the negative charge inside the cytosol?

A

protein anions and RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Is a cell slightly negative or positive on the inside? Which has a bigger gradient, K+ or Na+?

A

Slightly negative on the outside, resting potential of approx. -60mV. K+ has the bigger gradient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is there more potassium inside or outside of the cell?

A

Inside.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When the cell becomes more highly permeable to Na+, the cell becomes closer or further away from it’s threshold for action potential?

A

It becomes closer. Adding Na+ makes the cell more positive, it depolarizes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two types of ion channels?

A

Ligand and voltage-gated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What did patch clamping prove

A

Patch clamping showed that the voltage that comes through a Na+ channel is always the same, therefore the channel is either open or closed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the range of the average action potential? What is resting potential? The peak of the electrical potential? The level of hyperpolarization? And how long does the whole thing take?

A

Resting potential: 60mV
Peak: +40mV
Hyperpolarization: -75mV
time: ~5ms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What begins the action potential?

A

Na+ entering the cell is what begins the action potential. Once it hits the threshold of about -40mV, then the AP takes place.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the difference in permeability between Na and K during the rest period and during the action potential?

A

Rest: ~100 more permeable to K
AP: ~10 more permeable to Na

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Do signals travel down the nerve in one wave, or with many action potentials?

A

In many action potentials. In myelinated nerves, each node of Ranvier is the site of a new action potential.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two types of synapses, and how are they different?

A

Chemical: The pre- and post-synaptic sides are separated by the synaptic cleft (~50nm) and neurotransmitters are secreted via exocytosis to the next cell. These secretions can be inhibitory or excitatory.

Electrical: pre- and post-synaptic sides are connected by gap junctions. Signals are passed with virtually no delay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the two types of receptors that neurotransmitters can affect?

A

Ionotropic: ligand gated cells, in which the passageof the neurotransmitter directly affects the cell.

Metabotropic: affect cell through a secondary messenger, commonly a GPCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a neurotransmitter?

A

Any signaling molecule released by a neuron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do excitatory receptors do?

A

They cause the cells to depolarize (get closer to an AP). Inhibitory receptors cause polarization.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Synapses that use AcOh are known as what type of synapses?

A

cholinergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the most common neurotransmitter outside of the CNS? Is it excitatory or inhibitory?

A

Acetylcholine, excitatory.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the derivatives of tyrosine? What is the name of these hormones?

A

The derivatives are dopamine, epinephrine, and norepinephrine. These are known as catecholamines.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where are catecholamines synthesized?

A

Adrenal Gland.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What triggers secretion of neurtransmittersin the bouton?

A

Calcium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Are the calcium channels in the bouton voltage or ligand gated?

A

voltage gated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What binds to the nicotinic receptor? Is it excitatory or inhibitory? Is it ligand or voltage gated?

A

nicotinic acetylcholine binds and it is excitatory. It causes Na+ ions to rush in. It is ligand gated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Is the GABA recptor ligand or voltage gated? What does it facilitate the transport of?

A

It is ligand gated and it facilitates the transport of Cl- ions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the two ways that neurotransmitters are done away with after they are used?

A

Degradation or re-uptake. Some times they float away and diluted.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the function of acetylcholinesterase?

A

It hydrolyzes acetylcholine into acetic acid and choline.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
What is an excitatory PSP? Inhibitory? Is the ratio of action potentials one to one when going from one neuron to another?
Post synaptic potential is the different in potential to the next neuron in line (post synaptic neuron). Excitatory depolarizes, inhibitory increases the polarity. The ratio is not one to one. It can take several shots of neurotransmitters to affect an action potential in the adjacent cell.
25
What are the two ways that a post synaptic action potential can be triggered?
Repeated firings from the same neuron, or multiple firings from different neurons. A single neuron can receive information from literally thousands of other neurons.
26
What is the order of events from GPCR to cAMP?
ligand binds to GPCR, activated G protein (alpha subunit) floats over to adenylyl cyclase which uses ATP to make cAMP.
27
What is the order and magnitude of adenyly cyclase to other substrates?
AC activated multiple cAMP, 2 cAMP activate one protein kinase A, PKA activates thousands of substrates.
28
what deactivates cAMP?
phosphodiesterase.
29
What are two functions of epinephrine? What sort of receptor does it work through?
Break down glycogen (glycogenolysis) and inhibit production of more glycogen. It works through a GPCR.
30
What are the four types of tissue?
Connective, epithelial, nervous and muscle.
31
What are the 5 groups of hormones/pathways?
1. Pancreatic 2. Adrenal 3. HT-PP 4. HT-AP-End Gland 5. HT-AP-Other
32
What hormone does the pancreas release? The adrenal medulla?
Pancreas: glucagon, insulin | adrenal medulla: epinephrine
33
How are the hypothalamus and posterior pituitary connected? What does the PP release?
They are connected directly by neurons. The PP releases vasopressin (secretes milk) and oxytocin (express milk).
34
What are the tropic hormones? Where do they go?
Adrenocorticotropic hormone: goes to adrenal cortex, makes cortisol, sex steroids, aldosterone Thyroid Stimulating hormone: goes to thyroid, makes thyroxin Follicle Stimulating hormone: goes to gonads, makes androgen, progesterone, estrogen
35
What are the "Other Hormones?"
enkephalins, prolactin, endorphins, GH, MSH
36
How are the HT and AP connected?
capillaries, any messages must go through the blood. Portal Vein
37
What type of receptors are adrenergic receptors? Which binds better to epi and which to norepi?
adrenergic receptors are GCPRs. Epi binds better to the beta, and norepi binds better to alpha.
38
What are the two types of tissue in the pituitary gland?
AP: epithelial from the mouth PP: neural from brain
39
What are the stages for the HT/AP pathway?
HT - releasing hormone - AP - tropic hormone - Target Gland - hormone - Target Tissue - action
40
What does glucagon do?
It breaks down glycogen. f
41
What ion is PKC dependent on?
Ca++
42
Where is Ca++ held inside the cell? What messenger releases it? What is the total sequence to release Ca++?
the ER. It is released by IP3. Sequence: 1. hormone bind to extracellular receptor 2. activates G protein 3. activates phospholipase C 4. breaks down PIP2 to release IP3 5. binds to receptor on ER 6. opens Ca++ channels in ER 7. Ca+ flows down gradient.
43
How are DAG and IP3 made? What is the starting material? What can block this pathway?
Phospholipase C hydrolyzes PIP2 into DAG and IP3, both of which are second messengers. Lithium can block this pathway.
44
How does PIP2 affect PKC? What is the pathway from extracellular ligand?
1. ligand binds to receptor, activates G-protein 2. G-protein activates phospholipase C, which breaks PIP2 into IP3 and DAG 3. IP3 opens Ca++ channels on ER 4. Ca++ and DAG together turn on PKC 5. PKC phosphorylates enzymes and other substrates
45
What is the difference between an agonist and antagonist?
Agonist: mimics the effect of the hormone Antagonist: blocks the effect of the hormone
46
The DAG/IP3 pathway can be can be initiated using what type of receptor?
1. GPCR | 2. TK receptor
47
What can stimulate hypothalamus?
nerves from brain, hormones from target organs (ie- ovary, thyroid), and ion concentration is fluid surrounding it (ie- glucose, Na+)
48
What is the only glad that uses ducts?
exocrine glands.
49
What is the pathway for making thyroxin?
1. thyroglobulin (TG) is made in thyroid follicle cell (made on RER and exocytosed into lumen) 2. iodine enters cell via Na symport goes to lumen 3. thyroperoxidase turns iodine into molecular iodine 4. iodine attaches to TG 5. TG is brought back into cell and is degraded by lysosomes into TH 6. TH is lipid soluble and diffuses out of cell
50
What does thyroxin inhibit the production of?
Thyroid Releasing Hormone from HT and Thyroid Stimulating Hormone from AP
51
Is TH lipid soluble?
yes.
52
What kind of hormones are made first as pre-pro hormones (pre-pro: in inactiveform plus signal sequence)?
Only peptide hormones.
53
The hypothalamus is the integrator for what system?
temperature.
54
Does ADH increase or decrease water retention?
increase.
55
Dopamine inhibits what?
Dopamine is the primary inhibitor of prolactin. Decreasing dopamine increases prolactin which leads to lactation. (oxytocin is used to express the milk.
56
What are some peptide hormones?
insulin, glucagon, prolactin, TSH, ADH, TRH)
57
Name some steroid hormone.
estrogen, progesterone, testosterone, aldosterone, cortisol
58
What is the only hydrophobic hormone that can be stored? How is it stored?
Thyroid hormone can be stored as thyroglobulin. This has important implications for the ability to store iodine which is not guaranteed in our everyday diet. We can store up to a 6 month supply of iodine.
59
What hormone(s) increase glucose in the blood, and what hormone(s) decrease the amount of glucose in the blood?
Glucagon and epinephrine increase glucose in the blood. Insulin decreases glucose in the blood.
60
What are the effects of insulin on muscle, adipose tissue and liver?
1. Muscle: stimulates glucose transport, stimulates glycogenesis 2. Adipose Tissue: stimulates glucose transport 3. Liver: stimulates glucose transport, stimulates glycogenesis, stimulates glucokinase which makes G6P
61
What is the difference between the sympathetic and parasympathetic nervous system?
sympathetic responds to a crisis, parasympathetic is for a relaxed state.
62
What transmitter does the sympathetic nervous system use? The parasympathetic?
Sympathetic: norepinephrine Parasympathetic: acetyl choline
63
Which has a greater push, Na+ in or K+ out?
Na+ in, it has both electrical and gradient.
64
What basic type of receptors are nicotinic and muscarinic? What differences to they have?
They are both cholinergic receptors and in the PNS. Nicotinic is direct (it's a Na+/K+ channels), contracts muscles (excitatory only). Muscarinic is indirect (uses GPCR), and can be excitatory or inhibitory (slows heart rate).
65
Can muscle break down G6P?
No, it can't take off the phosphate and break it down to glucose, so it breaks it down to lactate. The lactate is sent to liver in the blood, and the liver can perform gluconeogensis to re-make the glucose.
66
Who can release glucose to the blood?
Only the liver because the liver has G6-phosphatase. The muscle can release lactic acid, and adipose tissues can release fatty acid.
67
What is a muscarinic receptor?
They are GCPRs, associated with lots of different G proteins, it always results in opening ligand gated ion channels. These is a cholinergic.
68
are muscarinic receptors ionotropic or metabotropic?
metabatropic.
69
is a nicotinic receptor metabotropic or ionotropic?
ionotropic.
70
Will an antagonist change the conformation of its receptor?
no.
71
are adrenergic receptors metabotropic or ionotropic?
metabotropic.
72
The first nerve from the CNS to the peripheral nervous system is what type of neuron.
Motor neuron, and it's neurotransmitter is always ACh.
73
The first neuron in the SNS and PNS use what type of neurotransmitter?
The first neuron always uses ACh.
74
The somatic and autonmic nervous systems have their first cell body where?
in the spinal chord.
75
Compare the somatic and autonomic nervous systems
Somatic: consists of single neuron from spinal chord to muscle, only innervates skeletal muscles, always uses AcCh on nicotinic receptors (direct/ionotropic), can only excite Autonomic: uses two nerves, the first almost always uses AcCh and excites, the second uses norephinephrine (nicotinic, sympathetic) or AcCh (muscarinic, parasympathetic), sympathetic has ganglia close to spine, PNS has ganglia far away,
76
What are the two systems of sensory neurons? Are they direct or indirect?
2 Cell: First cell is exposed to sense, releases transmitters which cause AP in second cell 1 Cell: One cell is exposed to sense and has an AP. Both can be either direct or indirect.
77
What are some similarities between the adrenal cortex and medulla?
Medulla: stimulated by nerves, can store epinephrine Cortex: stimulated by hormones, must make cortisol on the spot because it is lipid soluble and can't be stored.
78
what type of hormone do all tropic hormones inspire the production of? How are they stored?
They inspire the production of steroids, all of which are lipid insoluble so they can't be stored.
79
Does cortisol have negative feedback regulation?
yes.
80
What is the receptor for cortisol? How is cortisol synthesis inhibited?
A transcription factor. So inhibition affects transcription.
81
Are cortisol and TH regulated variables?
Yes, they are kept at normal homeostatic levels and are regulated. They are needed all the time.
82
What is equilibrium potential?
When the electrical force and concentration gradient balance each other out.
83
What deactivates G proteins?
Hydrolysis of the alpha subunit, going from GTP to GDP.
84
What makes cAMP? What degrades it?
Adenyl cyclase makes cAMP, and phosphodiesterase degrades it.
85
What does "hyper" mean?
high
86
What is the production of lactate in the muscle dependent on?
Whether or not lactate is made is largely dependent on the presence of oxygen.
87
What is the pathways of epinephrine for skeletal muscles? Smooth muscles of heart? Smooth muscles in arterioles?
Skeletal: beta-adronergic, G-protein, AC, cAMP, PKA, phosphorylase kinase, glycogen, G1P Heart: beta-adronergic, G-protein, AC, cAMP, PKA, MLCK (inhibits this), relaxation (no contraction) Arterioles: alpha-adronergic, G-protein, PLC, PIP2 is broken-down, IP3 releases Ca++, Ca++ in cytosol, contraction
88
All HT hormones, except dopamine, are peptides.
that's a fact.
89
does exocytosis have to mean things leaving the cell?
apparently, TM proteins are exocytosed.
90
Don't forget the difference between net number and concentration!
.

From Flashcardlet (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions