Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology 1510 > Chapter 9 > Flashcards

Chapter 9 Flashcards

1
Q

G protein

A

transmembrane protein that consists of 7 alpha helix that pass through the lipid bilayer 7 times

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

g protein subunits

A

alpha beta gamma

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

active vs inactive g protein

A 
inactive = gdp bound to alpha subunit
active= gtp bound to alpha subunit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

describe the process that requires a GCPR receptor

A

the activation of the receptor is done by different neurotransmitters (synaptic signaling) that causes gcpr receptor to bind to g protein and exchange its gdp for gtp. The g protein then dissociates and gtp binds to the alpha subunit of and pulls away leaving behind the beta-gamma subunit.

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

what happens to gtp bound alpha subunit of g protein

A

it binds to an effector protein

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

Adenylyl Cyclase bound to gtp bound alpha subunit of g protein?

A

becomes enzymatically active and catalyzes the conversion of atp to CAMP, which binds to and activates PKA and then phosphorylates specific proteins leading to specific cellular responses (response proteins)

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

CAMP

A

CAMP is a second messenger signaling protein that originated inside the cell

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

PKA

A

protein kinase a

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

Response proteins of PKA

A

1) increased heart rate
2) breakdown of glycogen and glucose in skeletal muscles
3) breakdown of fats to fatty acids in fat cells

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

phospholipase c bound to gtp bound alpha subunit of g protein

A

activates and then cleaves (splits) PIP2 into IP3 and DAG (both act as 2nd messengers). IP3 opens CA2+ channel and releases Ca2+ and the binds to CA2+ binding proteins. where as DAG will signal the molecules of ATP

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

Ca2+ ion channel

A

because the lumen of smooth er has more Ca2+ than the cytoplasm and the Ca2+ ion channel is moving Ca2+ from the lumen to the cytoplasm and moving down the concentration gradient this is an example of passive transport

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

effects of phospholipase c

A

glycogen breakdown, amylase secretion, muscle contractions, aggregation

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

Vasopressin (protein hormone)

A

target tissue is in the liver and is responsible for glycogen breakdown

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

Acetylcholine (a)

A

target tissue is in the pancreas and secretes amylase which is a digestive enzyme

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

Acetylcholine (b)

A

target tissue is in the smooth muscle cells and causes contractions

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

Thrombin

A

target tissue is in blood platelets and causes aggregation which plays a very important role in blood clotting

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

diff receptors can produce the same 2nd messenger (ex?)

A

epinephrin and glucagon are two receptors that produce the same second messenger therefore producing similar results; they both stimulate the liver cells to breakdown glycogen to glucose-6-phosphate. they both bind to glucagon specific g protein receptors found in the plasma membrane of liver cells and completes the cycles of gcpr and adenylyl cyclase accordingly

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

what other receptors do liver cells have?

A

insulin (RTK) which lowers the blood glucose levels by converting glucose to glycogen therefore lowering the blood glucose levels.

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

define cellular communication

A

how cells attain signals from outside, how they respond to those signals and how they interact with each other

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

how do cells “talk”

A

the signaling cell produces a signal or a ligand and those ligans bind to the receptors of the target cells which responds to that signal

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

what can ligands be

A

they can be proteins, peptides, amino acids, steroids, fatty acid derivatives, or dissolved gasses.

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

what are the two different types of receptors

A

intracellular and membrane/cell surface

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

what is the intracellular receptor

A

it is found inside the cell usually in the cytoplasm or nucleus; they use hydrophobic ligands and simple diffusion to move across the plasma membrane; the ligands that usually bind to these receptors within the cells are steroids, gasses, and fatty acid derivatives

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

what is a membrane receptor

A

they are receptors that are embedded into the membrane they attach to hydrophilic ligands such as proteins, peptide bonds, or polar amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is the signal transduction pathway
converts the information in the signal into a cellular response
26
what are the different types of signaling
direct contact, paracrine, endocrine, synaptic, and autocrine
27
direct contact / contact dependent signaling
when a signal molecule on the plasma membrane of one cell contacts the receptor molecule on the adjacent cell it is very important in early development it uses gap junctions to allow exchange of ions, amino acids, and sugars
28
how is direct contact signaling important for early development
it allows cells that are initially similar to become specialized
29
how do gap junctions work in regards to direct contact signaling
they are gap channels made of proteins connexions that bond together between the plasma membrane of one cell to the adjacent membrane of another allowing for an exchange
30
what kind of receptor does direct contact signaling have
membrane bound receptors
31
paracrine signaling
is when the signaling cell releases short lived ligands that affect nearby target cells
32
what are short lived ligands
an example are usually growth factors or proteins that stimulate cell growth and division
33
give an example of paracrine signaling
for example when we get a paper cut, growth factors bind to receptors which will lead to the duplication of cells therefore causing the cut to heal
34
endocrine signaling
the signaling cell releases long lived ligands that travel through the circulatory system to induce several distant target cells; both animals and plants use this mechanism extensively
35
what are the long lived ligands in endocrine signaling
hormones; they're found in the endocrine glands
36
what are the endocrine glands
they are made of endocrine cells that release hormones into the blood to get distributed
37
give an example of endocrine signaling
when the levels of glucose in our blood increase, the beta cells of the pancreas release insulin hormones are released into the blood where they bind to the target distant cells which have insulin receptors located on fat, liver, and skeletal muscle cells which then convert excess glucose and glycogen in the skeletal muscle cells and liver cells but convert excess glucose to fats in fat cells
38
synaptic signaling
occurs when the nerve cells release short lived ligands (neurotransmitters) into the gap (synapse, which forms between the nerve and its target cell
39
what forms between the nerve and target cell
a synaptic guy
40
what can the target cell be in synaptic signaling
another nerve cell, muscle gland, or endothelial cells
41
what are endothelial cells
they line blood vessles: capillaries, arteries,
42
besides being a short lived ligand, what are neurotransmitters
they are chemical signals released by the nerve cell into the synaptic gap
43
autocrine signaling
when the cell sends a signal to itself; when the released ligand binds to the receptors of the same signaling cell the released the ligand
44
give an example of autocrine signaling
in the presence of pathogens t cells produce ligands (growth factors) that bind the tcell receptors that produce them causing a divide meaning that they can provide a better immunity defense response
45
what are the two types of intracellular receptors
steroid receptor or no receptor
46
what type of steroid hormones could there be
testosterone, cortisol, estrogen
47
what is cortisol
it is a hormone that is found in the adrenal glands on top of the kidney
48
what happens after the steroid ligand is release
it binds to the steroid-hormone receptor; the ligands released to bind are hydrophobic ligands (they use facilitated diffusion/simple diffusion to move across the membrane)
49
what does hormone binding do to the inhibitor
it alters the receptor conformation so it no longer binds to the inhibitor
50
what is the inhibitors preventing before the hormone binds to the receptor
it is blocking the DNA binding site for transcription which will therefore prevent translation; because it affects transcription it also affects gene expression and prevents any of these three processes to happen
51
what happens after the inhibitor is unable to bind to the DNA binding site due to the hormone ligand binding to the receptor
the hormone receptor complex translocates to the nucleus
52
what occurs after the complex translocates to the nucleus
the hormone receptor complex binds to the DNA which usually turns on transcriptions (but also has the ability to turn it off)
53
what is the overall cellular response to the signaling that occurs after the steroid hormone ligand binds to the receptor
the overall response is a change in gene expression
54
what is an example of a type of signaling that requires no receptor. If able to name one, what does it require instead
one type of signaling is known as nitric oxide signaling and instead of a receptor it uses guanylyl cyclase
55
what is the primary function of nitric oxide signaling
to provide assistance for vasodialation
56
what is the purpose of vasodialation
provides an increase of blood flow into the body to tissues that need it the most
57
what produces nitric oxide
it is produced by the lining of the the blood vessels known as the endothelial cells
58
how does nitric oxide signaling work
first a nerve cell releases a short lived ligand usually a neurotransmitter which then binds to the receptor of its target cell, in this case endothelial cells, where the signal sent will convert L-arginine into Nitric Oxide which then rapidly diffuses across the membrane (paracrine signaling) through simple diffusion because the ligand is hydrophobic therefore activating the intracellular receptor. After rapid diffusion it does not bind to a receptor instead it binds to guanylyl cyclase which converts gtp to cyclic guanosine monophosphate (cGMP) therefore leading to vasodilation relaxing the smooth muscle cells
59
what is viagra used to treat
it is used to treat erectile disfunction in men
60
what are the two functions of guanylyl cyclase
guanylyl cyclase is made to be enzyme and can act as a receptor
61
what can happen sometimes that causes erectile disfunction
erectile disfunction occurs after the conversion of GTP to cGMP when the enzyme phosphodiesterase catalyzes the conversion of cGMP to GMP which stops blood flow (vasoconstriction)
62
what does viagra do that helps to stop erectile disfunction
it acts as an inhibitor to the enzyme phosphodiesterase to stop the conversion of cGMP to GMP
63
what are membrane (cell surface) receptors
they are the majority of our receptors that are not inside our cells but rather they are embedded into the membrane
64
what are the three membrane receptors
chemically gated ion channels, enzyme coupled receptors, G protein coupled receptors
65
what happens in a chemically gated ion channel
the specific ligand which is usually a neurotransmitter binds to the receptor and then acts like an ion channel allowing the passage of of specific ions such as Na+, K+, Ca2+, or Cl-
66
why doesnt the ligand cross the membrane
because it is hydrophilic
67
what are examples of chemically gated ion channels
the acetyl choline receptor binds the neurotransmitter acetyl choline to itself in the plasma membrane of skeletal muscle cells which then allows only Na+ ions to pump because it behaves like a sodium ion channel
68
what is acetyl choline
it is the most common neurotransmitter in the body produced by nerve cells)
69
what are enzyme couples receptors
they are receptors that act like enzymes or associate themselves with enzymes found inside our cells and they are activated by ligands
70
what are the most common enzyme coupled receptors
almost all of them are protein kinases which phosphorylate themselves or other proteins
71
what is the most common enzyme coupled receptor
tyrosine kinases
72
what is the overall purpose of tyrosine kinases receptors
they influence the cell cycle, cell migration, cell metabolism, and cell proliferation
73
what are the parts of the receptors tyrosine kinases
the extracellular ligand binding domain - where the hormone / growth factor ligand binds the intracellular kinase domain - made of many tyrosine amino acids and a single alpha helix
74
what happens after the ligands bind to the tyrosine kinase receptors
they two receptors come together to form a dimer which then attach inorganic phosphates to the tyrosine from 8 atp molecules and response proteins bind to the phosphate groups which phosphorylates proteins
75
why does dimerization occur
to activate kinases to transfer phosphate groups from atp attaches to tyrosine
76
what are specific examples of RTKS
insulin receptors
77
what is the purpose of insulin receptors
insulin will bind to extracellular domain to phosphorylate insulin response proteins to activate glycogen synthase to convert glucose into glycogen and lower blood glucose levels
78
what is the enzyme phosphatases
enzymes that dephosphorylate different phosphorylated proteins
79
what are kinase cascades
they are kinases that amplify a signal because a few signal molecules elicit a large cellular response

Biology 1510 (13 decks)

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