exam 1 Flashcards
(175 cards)
1
Q
needs of a cell
A
source of nutrients
source of oxygen
elimination of wastes
maintenance of water and ions
2
Q
homeostasis
A
constant internal, physical, and chemical conditions
keeping values within a normal range
3
Q
types of tissue
A
epithelial
muscular
connective
nervous
4
Q
epithelial tissue
A
lining of organs
5
Q
muscular tissue
A
skeletal, smooth, cardiac
specialized for contraction and movement
6
Q
connective tissue
A
tendons and ligaments
strength inducing
7
Q
nervous tissue
A
critical for physiological function
cell-cell communication
8
Q
integumentary system
A
skin, hair, sweat
protection, defense, and regulation of temp
9
Q
endocrine system
A
hormone-secreting glands
metabolism, homeostasis, etc
10
Q
reproductive system
A
female: ovaries, etc, produce eggs
male: testes, etc, produce sperm
11
Q
circulatory system
A
heart, blood vessels, blood
movement of blood through body
12
Q
respiratory system
A
nasal passages, trachea, lungs
establish air route and oxygen regulation
13
Q
urinary system
A
kidneys, ureters, bladder
filter blood, regulate plasma, remove waste in urine
14
Q
musculoskeletal system
A
bone, skeletal muscle, cartilage
movement, support, production of blood cells
15
Q
digestive system
A
mouth, stomach, liver, intestine
breakdown food matter to absorb nutrients
16
Q
percent of fluids in body
A
60%
17
Q
percent of solids in body
A
40%
18
Q
intracellular vs extracellular fluid makeup
A
2/3 intracellular
1/3 extracellular
19
Q
makeup of extracellular fluid
A
75% interstitial fluid (Fluid outside cells)
25% plasma
20
Q
diffusion
A
net movement of molecules from high concentration to low concentration (Down concentration gradient)
- no energy required (passive)
- everything is always moving, even in equilibrium!
21
Q
what influences diffusion
A
- temperature
- mass of molecule (smaller, moves faster)
- surface area (large SA, diffusion occurs rapidly)
- medium (more rapid in gas)
medium doesn’t change in our body because it occurs between interstitial fluid and extracellular fluid
22
Q
fick’s first law
A
rate of diffusion is proportional to surface area and the difference in concentration (magnitude of concentration gradient)
23
Q
space and diffusion
A
- distance molecule travels to destination
- as distance increases, time increases by a factor of 10
24
Q
membrane permeability
A
proportional to lipid solubility/molecular size
25
ion channels
- made of a protein/group of proteins
- selective for specific ions or group of ions (based on charge/size)
- ions is still simple diffusion
26
non-regulated protein channels
always open, called leak channels
responsible for charge differences across membranes
27
voltage gated channels
channels regulated by electrical charge across membrane
open/close depending on membrane potential
28
ligand gated channel
regulated by presence of certain chemicals that can bind to channel
ex/ neurotransmitter
29
mechanosensitive channel
regulated to stretch of membrane
ex/ touch receptors
30
mediated transport
uses a carrier protein which doesn't have to have access to both inter and extra space at the same time
31
what affects rate of mediated transport
- relative affinity (how tight molecule and transport are)
- how many transporters
- how fast transporters work
32
diffusion vs mediated transport
mediated transport has transport maximum
will reach a point where all carrier proteins are working
33
types of mediated transport
- facilitated diffusion
- primary active transport (ATP)
- secondary active transport (conc. gradient)
34
primary active transport
uses energy directly derived from cleavage of ATP to drive conformational change in transport protein, which results transport of ion
- can move ions against concentration gradient
35
sodium potassium pump direction
antiport
(opposite direction)
36
calcium pump direction
uniport
(only one thing moving)
37
hydrogen pump direction
uniport
(only one thing moving)
38
hydrogen potassium pump
antiport
(opposite direction)
39
sodium potassium pump
each cycle:
- uses one ATP
- 3 Na+ are transported out of cell
- 2 K+ are transported into cell
asymmetrical pump --> contributes to making inside cell negative
type of primary active transport
40
secondary active transport
uses energy in a concentration gradient, typically from sodium, to drive the transport of another molecule
- sodium potassium pump creates ion gradient
- sodium glucose symport transporter transports glucose from ECF
- releases glucose into cytoplasm
41
vesicle mediated transport
exocytosis: vesicular membrane fuses with the cell membrane, then the contents of vesicle are released into ECF
endocytosis: cell membrane engulfs ECF, and then that section of plasma membrane pinches off into cell
42
osmosis
diffusion of water down its own concentration gradient due to aquaporins (water channel)
43
normal cell concentration
300 mOsm intracellular fluid
44
hypertonic solution
cell shrinks
45
hypotonic solution
cell swells
46
isotonic solution
no change in cell volume
47
apical membrane and basolateral membrane
two poles of cell
apical: microvilli and faces lumen
basolateral: faces ECF
48
absorption vs secretion in membrane
absorption: transport from lumen to ECF
secretion: transport from ECF to lumen
49
transcellular route
transported across cells
50
paracellular route
transported across the tight junctions between cells
51
transporters on apical and basolateral membranes
asymmetric localization of transporters allows for transcellular transport of solutes
52
allostasis
stability of optimal function through change
- the process by which the body responds to stressors in order to regain homeostasis
53
types of homeostatic control systms
negative feedback: something changes, mechanism changes it back
feed forward: body is anticipating that change will happen and implements mechanism before it happens
54
negative feedback system
works around an error signal to approximate the set point
1. imposed change (shift outside homeostasis range)
2. sensor gives signal to evaluator
3. effector makes it return to normal
55
feedforward control
not positive feedback!
1. stimulus
2. evaluation of expected change
3. effector compensates for change before it occurs
56
positive feedback system
non homeostatic! but can contribute to homeostatic systems
response reinforces stimulus, sending variable farther from set point
changes in same direction, increases stimulus
ex/ birth of baby
57
intercellular communication
electrical signaling: 2 cells connected by ion channels
chemical signaling: contact, local, long distance
58
paracrine signaling
local
secretory cell releases molecule, target cell releases receptor
diffusion from point source
59
autocrine signaling
secretory cell and target cell are same
60
cytokine signaling
secretory cell and target cell release cytokine into blood vessel
combination of paracrine/endocrine signaling
61
neurotransmitter signaling
local
secretory cell (Neuron) releases signaling molecule down axon to terminal, doesn't have to travel far
only travels between synapse (space between)
62
hormone (endocrine) signaling
long distance
secretory cell releases hormone which diffuses into blood cell and distributed to entire body in circulatory system
but only has effect on the cells that release the receptor
63
neurohormone signaling
long distance
neurohormone released from neuron (not cell)
travels along blood vessel to target cell
64
what to consider about chemically mediated intercellular communication
- nature of messenger molecule
- if its diffused or travels through blood circulation
- how is receiving cell influenced by messenger
65
receptors
proteins that bind to messenger molecule and the interaction between messenger molecule and receptor protein elicits a response
66
antagonist receptor
competes with ligand for binding to receptor but doesn't have signal, just blocks
67
agonist receptor
mimics cell's signaling receptor
binds to receptor and triggers cell's response
68
down regulation and receptor
decrease in total number of receptor cells
69
up regulation and receptor
increase in total number of target receptor
70
increased sensitivity and receptor
increased responsiveness of a target cell to a messenger
- may result from up regulation
71
lipid soluble messengers
act to alter transcription of particular genes or activity of specific enzymes
plasma membrane receptors
- can be ion channels
- can be enzymes
- can be activate g-proteins
can diffuse into cells and interact with intracellular receptors
72
lipophopbic signaling molecules
cannot diffuse into cells so must interact with receptors in the membrane
73
calcium as second messenger
- binds to calmodulin, with calcium-calmodulin complex then activating a variety of cellular enzymes
- binds to other calcium-binding intermediary protein
- binds to proteins to produce a direct response
74
g-protein coupled receptors
(metabotropic)
- binding of an agonist (First messenger) to receptor --> causes dissociation of g-protein complex
- one of the g-protein components is free to diffuse away and interact with another protein
75
signal amplification by enzyme cascades
1. signal molecule binds to g protein receptor, activates g-protein
2. g protein turns on adenylyl cyclase (amplifier enzyme)
3. adenylyl cyclase converts ATP to cyclic AMP
4. cAMP activaates protein kinase A
5. protein kinase A phosphorylates other proteins, leads to cellular response
76
endocrine vs exocrine gland
endocrine: secretes hormones into interstitial fluid (Ductless)
exocrine: secretes molecules into lumen on organ through duct
77
endocrine vs neural
neural: local, fast, precise, interact with external environment
endocrine: slow, long, control for internal organs
78
regulatory aspects of endocrine system (6)
1. regulation of metabolism, ions, H2O
2. response to stress
3. smooth, sequential growth/development
4. reproduction
5. maintenance of blood cells
6. integration with autonomic nervous system
79
hypothalamus hormones
neuron
tropic hormones (P)
release or inhibit pituitary hormones
80
posterior pituitary hormones
oxytocin, vasopressin
81
anterior pituitary (G) hormones
prolactin, growth hormone
corticotropin, thyrotropin
82
thyroid gland hormones
triiodythyronine and thryoxine
calcitonin
83
heart hormones
atrial natriuretic peptide
target kidneys, increases sodium excretion
84
stomach and small intestine hormones
gaestrin, cholecystokinin, secretin
GI tract and ancreas, assist digestion and absorption of nutrients
85
pancreas hormones
insulin, glucagon, somatostatin, pancreatic polypeptide
86
adrenal cortex hormones
aldosterone: kidney, sodium-potassium homeostasis
cortisol, androgens: many tissues, stress response
87
adrenal medulla hormones
epinephrine, norepinephrine
- fight or flight response
88
testes hormones
androgens: manu tissue, sperm production
inhibin: anterior pituitary: inhibits FSH secretion
89
ovaries hormones
estrogen, progesterone: manu tissue, egg production
inhibin: anterior pituitary, inhibits FSH secretion
relaxin: pregnancy, uterine muscle, relaxes muscle
90
peptide hormones
- synthesis and storage
- release from parent cell
- transport in blood
- half life
- location of receptor
- response to receptor-ligand binding
- general target response
- examples
- made in advance and stores in vesicles
- released by exocytosis
- dissolved in plasma
- short half life
- receptor in cell membrane
- when ligand binds to receptor, activation of second messenger
- targets modification of existing proteins
- ex: insulin, parathyroid, hormone
91
steroid hormones
- synthesis and storage
- release from parent cell
- transport in blood
- half life
- location of receptor
- response to receptor-ligand binding
- general target response
- examples
lipid soluble
- synthesized on demand
- simple diffusion
- bound to carrier proteins
- long
- cytoplasm or nucleus
- activation of genes for transcription and translation
- induction of new protein synthesis
- estrogen, cortisol
92
catecholamines
- synthesis and storage
- release from parent cell
- transport in blood
- half life
- location of receptor
- response to receptor-ligand binding
- general target response
- examples
amine hormone
- made in advance and stored
- exocytosis
- dissolved in plasma
- short
- cell membrane
- activation of second messenger systems
- modification of existing proteins
- epinephrine, norepinephrine
93
thyroid hormones
- synthesis and storage
- release from parent cell
- transport in blood
- half life
- location of receptor
- response to receptor-ligand binding
- general target response
- examples
amine hormone
- made in advanced and stored
- simple diffusion
- bound to carrier proteins
- long
- nucleus
- activation of genes for transcription and translation
- induction of new protein synthesis
- thryoxine
94
protein/polypeptide hormone synthesis and release
1. protein synthesis gives rise to preprohormone --> goes into ER
2. enzyme chops off part of sequence, creates prohormone
3. prohormone passed from ER through golgi
4. prohormone put into vesicle that buds off golgi
5. vesicle has prohormone and enzymes that complete and cleave prohormone into final hormone
6. vesicle fuses with membrane and allows hormone to be released into extracellular space
95
peptide hormones
- cannot enter target cells and must combine with membrane receptors that initiate transduction processes
- most are g-protein
- exception: insulin
96
steroid hormone structure and synthesis
- biosynthetic precursor is cholesterol
- small differences in steroid structure can have big impact on function
97
types of steroid hormones
- mineralocorticoids: aldosterone
- glucocorticoids: cortisol
- sex steroids: estradiol, testosterone
98
actions of steroid hormones
1. hydrophobic steroids are bound to plasma protein carriers
2. steroid hormone receptors are in cytoplasm or nucleus
3. receptor hormone complex binds to DNA and activates/represses genes
4. activated genes create new mRNA that moves back to cytoplasm
5. translation produces new proteins for cell processes
- steroid cant store in vesicle because its lipid soluble, so it has to be synthesized on demand
99
tyrosine amine hormone
parent amino acid for catecholamines and thyroid hormones
- two types: catecholamines and thyroid hormone
- only thing in common is styrosine
100
catecholamines
made by modifying side groups of tyrosine
- ex: dopamine, norepinephrine, epinephrine
101
thyroid hormones
synthesized from 2 tyrosine and iodine atoms
- thyroxine and triiodothyrone
102
how are hormones released
- catecholamines: exocytosis from vesicles
- peptides: exocytosis from vesicles
- thyroid hormones: cleavage from thyroglobulin
- steroids: secreted as synthesized
103
what determines wether a cell responds
- whether or not it has a receptor
- whether the messenger is present in sufficient concentration to influence a sufficient number of receptors to elicit a response
104
what influences the level of hormone
largely secretion rate
clearance
105
what influences release of hormone
depends on specific hormone but
- changes in concentration of ECF ion
- changes in concentration of ECF organics
- neurotransmitter
- other hormone
- stretch
106
control of secretion of hormones
- negative feedback
- low plasma calcium detected, released paratyhroid hormone into blood, works on kidney, increases calcium
107
hypothalamus and pituitary
- hypothalamus is controlling brain structure, gives rise to tissue of posterior pituitary
anterior pituitary: true endocrine gland of epithelial origin
infundibulum: stalk that connects pituitary to brain
108
neurons in hypothalamus
paraventricular nucleus
supraoptic nucleus
- release vasopressin and oxytocin
109
PRH hormone
positive for prolactin
goes to breasts
110
PIH hromone
(dopamine)
negative for prolactin
goes to breasts
111
TRH hormone
positive for TSH
goes to thyroid gland, which releases TH
112
CRH hormone
positive for ACTH
goes to adrenal cortex, which releases cortisol
113
GHRH hormone
positive for GH
goes to liver, which releases insulin-like growth factors
or goes to cells throughout body
114
GHIH
somatostatin
negative for GH
goes to liver, which releases insulin-like growth factors
or goes to cells throughout body
115
GnRH
positive for endocrine cells like LH and FSH
goes to gonads
male releases androgens
female releases estrogen, progesterone
116
control pathway for cortisol secretion
- cortisol is secreted by adrenal cortex
uses negative feedback
117
structure of neuron
- dendrites
- cell body
- initial segment
- axon
- axon terminals
118
synapse
region where an axon terminal communicates with its postsynaptic target cell
119
myelin
- sheets surrounding axons
- unmyelinated segments form gaps called nodes of ranvier
- each individual glial cell lays myelin to insulate axons
120
CNS vs PNS
CNS: oligodendrocytes, myelinates several parts of several CNS axons
PNS: schwann cells, myelinates one part of one PNS axon
121
resting membrane potenitial
equilibrium potentials of permeant ions
- at rest: there is no net flow of ions, so membrane potential is constant
122
membrane potential for Na and K
resting membrane potential is closer to potassium because the membrane is more permeable to potassium ion than to sodium
- at rest, potassium is moving out (a lot, Due to leak channels) and sodium moving in (less)
123
afferent neurons
arriving to brain with information about sensory stimuli
124
efferent neurons
exit brain with information about motor
125
nervous system organizaation
central spinal cord system: brain and spinal cord
peripheral nervous system: everything else
126
afferent division
in peripheral nervous system
contains sensory and visceral stimuli and goes into brain
127
efferent division
in peripheral nervous system
- somatic nervous system: motor nerons to skeletal muscles
- autonomic nervous system: sympathetic/parasympathetic
128
somatic senses
afferent divison
touch, temperature, prain, joints
129
special senses
afferent division
vision, hearing, taste, smell
130
visceral senses
afferent division
blood pressure, ph, osmolarity, etc
131
dorsal of spine
back side
sensory info enters spinal cord
dorsal root ganglion (all cell bodies of afferent neurons entering spinal cord)
132
venral of spine
front side
motor info exits spinal cord
133
spinal cord division
- cervical cord
- thoracic cord
- lumbar cord
- sacral cord
134
cauda equina
spinal nerves extend past spinal cord
- lumbar nerves, sacral nerves, coccygeal nerves
135
cranial nerves
- 10th (vagas) nerve is biggest
- involved in parasympathetic nervous system
- extend out from ventral (bottom) of brain
136
sulci
grooves of brain
137
fissures
deep sulci/grooves
138
gyri
rounded region between sulci
139
blood brain barrier
- protects brain from substances in blood
- have tight junctions between capillary endothelial cells in brain (no pores)
- surrounded by astrocytes (glial cells) increase protection
140
ventricle
spaces within brain that are fluid filled and don't have tissue
141
circumventricular organs
part of brain not protected by blood brain barrier
142
parasympathetic
rest and digest
143
sympathetic
flight or fight
144
ganglion in parasympathetic system
- preganglionic neurons travel far
- postganglionic neurons ravel short
145
ganglion sympathetic system
- preganglionic neurons travel short
- postganglionic neurons travel far
146
somatic nervous system neuron signal
- efferent only, has one neuron
- neuron in skeletal muscle releases acetylcholine
- skeletal muscle has nicotinic acetylcholine receptor (ligand gated)
147
parasympathetic division neuron chain
- autonomic system
- preganglionic neuron in skeletal muscle release acetylcholine
- postganglionic neuron has receptor, then releases acetylcholine
- muscle has m-achr (g-protein)
148
sympathetic division neuron chain
- autonomic system
- preganglionic neuron in skeletal muscle release acetylcholine
- postganglionic neuron either: releases norepinephrine into muscle
- or epinephrine into blood (from adrenal medullla)
149
arterioles receptors
alpha-adrenergic receptor, causes them to constrict
150
arterioles receptors
alpha-adrenergic receptor, causes them to constrict
151
heart receptors
beta1-adrenergic receptor, increase rate
152
graded potentials
- decremental: decrease when farteher away
- can be depolarizing or hyperpolarizing
153
action potential
large depolariziation
154
absolute refractory period
occurs when voltage gated sodium channels are inactivated
during this time, it is impossible to generate antoher action potential, no matter how much stimulation is applied
155
relative refractory period
time after an action potential when enough channels have recovered from inactivation, but potassium flux is still active
156
hypothalamus
homeostasis, stress responses, endocrine control
157
thalamus
integrating region and relay site for sensory and motor information
158
cerebellum
coordination of movement
159
basal ganglia
movement, coordination
160
limbic regions
grouping of cortical and subcortical structures, involved with emotional state
161
parts of limbic region
- hippocampus: learning, memory
- amygdala: emotion
both deep in temporal lobe
162
cerebral cortex
sensory, motor control, integration of information
163
medulla oblongta
control of blood pressure, breathing, GI function
164
pons
relay between cerebellum and cerebrum (control of movement), coordination of breathing
165
pons and medulla
regulation of arousal and sleep, muscle tone, pain
166
peripheral system parts
somatics and autonomic
- autonomic is parasympathetics and sympathetic
- somatic is just motor neurons to skeletal muscle
167
postsynaptic poetential
graded potential in postsynaptic membrane of neuron
168
depolarizing
excitatory post synaptic potential (EPSP)
169
hyperpolarizing
inhibitory post synaptic potential (IPSP)
170
phases of action potential
1. depolarization from graded potential is so big, it causes Na+ voltage-gated channel to open (at axon hilcock)
2. Na+channel becomes blocked--> K+ channels open which repolarizes membrane (absolute refractory period) another action potential cant be generated
3. overshoots, becomes hyperpolarized (relative refractory period)
4. action potential travels down cell body to nerve terminal
171
what happens at nerve terminal with axction potential?
action potential converted from electrical to chemical signal
- voltage gated Ca2+ channels open, increase Ca+ concentration causes release of neurotransmitter through exocytosis, diffuse across synaptic cleft to receptor
172
infundibulum
stalk that connects pituitary to brain
173
anterior pituitary
true endocrine gland of epithelial origin
174
posterior pituitary
extension of neural tissue from hypothalamus
175
portal circulations and importance
- blood flow between 2 capillary beds
- important for circulation between hypothalamus and anterior pituitary
