Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Human Physiology Bio 340 > chapter six cell communication > Flashcards

chapter six cell communication Flashcards

1
Q

methods of cell-to-cell communication

A

gap junctions, contact-dependent signals, cells release messengers to ECF

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

gap junctions

A

direct cytoplasmic transfer between adjacent cells, transfer chemical & electrical signals, made of proteins called connexins

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

contact-dependent signals

A

surface to surface contact between membranes, require interaction between membrane molecules on two cells, relates to cancer cells

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

how do cells release messengers to the extracellular fluid?

A

long-distance communication (hormones, neurohormones, neurotransmitters), local communication (paracrine & autocrine)

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

what are the constraints for gap junctions & contact-dependent signals?

A

distance & small area of communication

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

how do channels and gap junctions differ?

A

channel connects ICF & ECF (cross one membrane), gap junction connects ICF to ICF (cross two membranes)

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

cellular messengers

A

long-distance communication & local communication

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

3 categories of long-distance communication

A

hormones, neurotransmitters, neurohormone

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

2 categories of local communication

A

paracrine agent & autocrine agent

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

hormones as cellular messenger

A

released from tissue & travels to target cell through blood

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

neurotransmitters as cellular messenger

A

released from neurons to adjacent effector (neuron can be measured in feet, message goes long-distance despite being delivered right next door)

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

neurohormones as cellular messenger

A

released from neuron & travels to target cell through blood

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

paracrine agent

A

released into interstitial fluid and affects neighboring target cell

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

autocrine agent

A

released into interstitial fluid and affects the cell that released it

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

hormones

A

secreted by endocrine glands or cells into blood. only target cells with receptors for the hormone will respond to the signal

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

neurotransmitters

A

chemicals secreted by neurons that diffuse across a small gap to the target cell. neurons use electrical signals as well

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

neurohormones

A

chemicals released by neurons into blood for action at distant targets

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

autocrine signals…

A

act on the same cell that secreted them

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

paracrine signals…

A

are secreted by one cell & diffuse to adjacent cells

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

long-distance communication

A

anytime we have the capability of sending it from one part of the body to a different part of the body

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

receptors

A

protein associated with the membrane or cellular interior which will bind a chemical messenger and exert an effector

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

what are the 5 characteristics of receptors?

A

highly specific (specificity), high affinity for specific messenger, they can be saturated or blocked, can undergo down-regulation & up-regulation

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

what influences affinity?

A

type & number of bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

down-regulation

A

decrease in receptor number in response to chronic elevated levels of messenger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
up-regulation
increase in receptor number in response to chronic low levels of messenger
26
5 steps of cell communication
1. signal molecule binds to 2. receptor protein activates 3. intracellular signal molecules alter 4. target proteins create 5. response
27
routes of messenger action: lipophilic messengers
diffuse directly through the membrane to an internal receptor (likes lipids)
28
routes of messenger action: lipophobic messengers
must enter cell through transport or bind to a surface receptor (bind to the outside, protein flexes, something happens on the inside)
29
transport proteins
designed to bind to a lipophilic messenger & carry it though the blood. most are amphipathic molecules. they last longer because they are carried by something else
30
what happens when we change the rate of transcription?
the cell is changed & doing something it wasn't before
31
what do lipophilic signal molecules bind to?
cytosolic or nuclear receptors (receptor in cytosol), SLOW- takes a while for message to get into nucleus
32
what do lipophobic signal molecules bind to?
receptors on surface of cell membrane, QUICK response (milliseconds)
33
signal transduction
message is conveyed from outside of cell to a new signal inside of the cell which then creates a cellular response
34
transducters
convert extracellular signals into intracellular messages which create a response
35
signal transduction benefits the cell through
signal amplification & multi-tasking
36
signal amplification
like a snowball, as we move along we get bigger and bigger all coming from one tiny messenger
37
multi-tasking
we can do multiple different things, one protein / response can create lots of different effects in the cell (kinase can phosphorylate different things in the cell)
38
lipophobic messengers act on 4 types of membrane receptors
1. ligand-gated receptor channels 2. receptor enzymes 3. GTP-binding proteins 4. integral receptors
39
ligand-gated receptor channels
receptor proteins that act as an ion channel. gated channel, ligand is our messenger, opened the channel
40
receptor enzymes
receptor acts as enzyme and messenger binding initiates enzymatic activity resulting in cellular response (activated the enzyme)
41
GTP-binding proteins
messenger activates a G-protein which opens an ion channel or activates an enzyme (most complex). the G protein either opens the channel or activates the enzyme, middle man
42
integrin receptors
messenger binding causes a change in the cytoskeleton
43
mechanisms of signal transduction
1. messenger binds to a ligand-gated channel 2. receptor enzymes 3. GTP-binding proteins
44
messenger binds to a ligand-gated channel
nicotinic (most common receptor in body), GABA, glycine
45
receptor enzymes
when activated, receptor enzymes act as enzymes to alter cytoplasmic proteins
46
kinase receptors
include many families of growth factors (insulin receptors, fibroblasts)
47
GTP-binding proteins (2nd messenger systems or G protein coupled receptors)
intracellular messenger (1st messenger) binds non-covalently to a surface protein & activates a G-protein that initiates an internal chemical (2nd messenger) that initiates the cell's response (second messenger inside the cell and causes response)
48
what is the cells response in second messenger systems?
either opening a channel or activating an enzyme
49
second messenger systems
1. cyclic AMP system 2. phospholipase-C pathway
50
cyclic AMP
chops off two phosphates (adenylyl cyclase enzyme) and attaches them to itself
51
cyclic AMP steps
1. signal molecule binds to G-protein & activates it 2. G protein turns on adenylyl cyclase 3. adenylyl cyclase converts ATP to cyclic AMP 4. cAMP activates protein kinase A 5. protein kinase A phosphorylates other proteins, leading to a cellular response
52
GPCR
the phospholipase C system
53
GPCR steps
1. signal molecule activates receptor & associated G-protein 2. G protein activates phospholipase C (PL-C amplifier enzyme) 3. PL-C converts membrane phospholipids into DAG (remain in membrane), IP3 diffuses into cytoplasm 4. DAG activates protein kinase C (PK-C) (phosphorylates proteins) 5. IP3 causes release of Ca2+ from organelles creating a Ca2+ signal
54
agonist
chemical messenger that binds to a receptor and triggers a cell's response
55
antagonist
molecule that competes with another for a receptor and binds to the receptor but does not trigger a cellular response (when it binds) (also called inhibitor, blockers)
56
what does the target response depend on?
the target receptor
57
epinephrine (adrenaline)
hormone, the messenger & receptor matters in terms of the type of response the body will have
58
signal termination
after the cell's response has been initiated, the first messenger must be stopped & the second messenger must be removed
59
first messengers can be:
degraded by extracellular enzymes (destroy messenger using enzymes) or endocytosis of receptor- ligand complex (broke down the messenger by bringing it in, binds to lysosol which brings destructive enzymes)
60
second messenger must be removed by
cannot degrade the second messenger when it is calcium, pumping ions out of the cytoplasm

Human Physiology Bio 340 (6 decks)

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