L1 & L2: Homeostasis & Cell Signaling Flashcards

1
Q

major types of fluid

A

intracellular and extracellular

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

extracellular fluid is composed of __

A

plasma and interstitial fluid

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

extracellular fluid serves as

A

buffer zone between cells and outside environment

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

what’s the percentage composition of three types of fluids out of overall volume?

A

plasma 7%
interstitial fluid 26%
intracellular fluid 67%

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

what’s the percentage composition of plasma and interstitial fluid out of extracellular fluid?

A

plasma 1/4

interstitial 3/4

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

homeostasis

A

dynamic stability of the internal environment of the body

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

in homeostasis, when the internal environment of the system is changed, ___

A

the system eventually returns to the set point

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

reflex

A

biological control system linking stimulus with response to maintain homeostasis

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

reflex arcs can be regulated by __

A

negative feedback

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

____ reinforce a stimulus

A

positive feedback

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

is positive feedback homeostatic?

A

no

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

paracrine signals

A

signals that affect nearby cells

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

autocrine signals

A

generated by the same cells upon which they act

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

when the target is close, cell communicate using

A

paracrine and autocrine signals

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

when the target is distant, cells communicate using

A

endocrine and neuronal signals

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

signaling molecules may trigger

A

a change in electrical potential, metabolism, gene expression, cellular motility

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

signal transduction

A

process by which cell converts one kind of signal into another

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

second messengers

A

molecules that direct, relay, and amplify signals

19
Q

two classes of extracellular signal molecules

A

ones that go directly into the cell (small and hydrophobic), and ones that bind to surface receptors (hydrophilic)

20
Q

what cells release NO?

A

endothelial cells

21
Q

what enzyme does NO signal activate?

A

gyanylyl cyclase

22
Q

where is gyanylyl cyclase located?

A

smooth muscle cell

23
Q

what does gyanylyl cyclase synthesize?

24
Q

how does viagra affect the pathway?

A

by inhibiting PDE that normally breaks down cGMP, prolonging the NO signal and penile erection

25
do steroid hormones require cell surface receptors?
no, they easily diffuse into the cell
26
what are three major classes of cell surface receptors?
G-protein linked, ion-channel linked, enzyme linked
27
inactive G-proteins
are bound by GDP at the alpha subunit
28
binding of the G-protein to receptor triggers ___
the exchange of GDP with GTP by the alpha subunit, activating the G protein
29
what enzyme does GS activate?
adenylyl cyclase
30
what enzyme does GQ activate?
phospholipase C
31
what process does adenylyl cyclase catalyze?
cAMP formation
32
what does cAMP activate?
protein kinase A
33
what enzyme is involved in the degradation of cAMP?
phosphodiesterase
34
what is one of the physiological actions of caffeine?
PDE inhibitor
35
a rise in intracellular cAMP can ___
activate gene transcription
36
second messengers involved in GQ pathway
PIP2, IP3, and DAG
37
what protein is activated in EGFR pathway?
Ras protein
38
Ras activates __
MAP-kinase cascade
39
enzyme-linked receptors have __
intracellular enzymatic domains
40
largest class of enzyme-linked receptors
receptor tyrosine kinases (RTKs)
41
activated RTKs cause
the assembly of an intracellular signaling complex
42
what is Ras?
monomeric G-protein involved in EGFR pathway
43
enzyme-linked receptors have __
intracellular enzymatic domains