Cell Signaling by Chemical Messengers Flashcards Preview

Foundations Test 1 > Cell Signaling by Chemical Messengers > Flashcards

Flashcards in Cell Signaling by Chemical Messengers Deck (52)
Loading flashcards...
1

Cell signaling vs. signal transduction

Signaling - between cells
Signal Transduction - extracellular signal converted to intracellular response

2

Cell signaling steps

Chemical messenger secreted by cell bc of stimulus
Messenger diffuses and transported to target cell
Specific receptor binds messenger
Binding elicits response
Termination

3

Specifity of receptor dictated by

Type of receptor and location

4

Most receptors bind

A single messenger type

5

Endocrine signaling

Cell sending out signal is pretty far away...usually transported through blood

6

Paracrine signlaign

Signaling cell is close

7

Autocrine signaling

Cell signals to itself

8

Nervous system messenging molecules and type

Small molecule neurotransmitters and neuropeptides
Paracrine

9

Endocrine system molecules and type

Endocrine
Endocrine hormones

10

Glucagon is ______ system and does what

Response to low glucose levels
Glycogenolysis
Endocrine

11

Immune system molecules and type

Cytokines
Auto, para, and endo

12

Eicosanoids molecules and types

Derived from arachidonic acid
Control response to injury
Para and auto

13

Growth factors molecules and type

Proliferation, differentiation, and apoptosis
Paracrine

14

4 receptor types from fast to slow

Channel-linked receptors (ionotropic)
GPCR (metabotropic)
Kinase-linked
Nuclear receptors (linked to gene transcription)

15

What can nuclear receptors bind?

Things that can get through membrane into the nucleus

16

Channel-linked receptors also known as

Gated ion channels

17

Agonist

Messenger that opens an ion channel

18

Example of Gated ion channel

Nicotinic acetylcholine receptor

19

Nicotinic acetylcholine receptor...what does it do, where is it found

Neuromuscular junctions - muscle contractions
Sense Ach and lets Na in and K out of muscle fiber

20

Nicotinic acetylcholine mechanism

AP in motor neruon
V gated ion channel lets Ca into cell
Vesicle of Ach fuses at post synaptic membrane
Ach diffuses and binds nicotinic acytylcholine receptor
Propogates signal through muscle fiber

21

How is acetylcholine receptor mechanism turned off?

Acetylcholinesterase degrades Ach

22

Myasthenia Gravis is what kind of disorder?

Acquired autoimmune

23

MG pathology

Produce antibodies to nicotinic Ach receptor...antibodies bind and cross-link receptor...complex andocytosed and degraded by lysosome...patient has fewer neuromuscular junctions and therefore lots of muscle fatigue

24

MG symptoms

Difficulty walking
Difficulty extending arms
Drooping eyelids

25

Tyrosine kinase receptors mechanism

Signal dimer binds
Kinase activity stimulated in the cytosol
Tyrosines phosphorylated
Intracellular proetins bind to phospho-tyrosine binding site

26

Tyrosine kinase receptors form _____ dimers

Homo

27

Tyrosine kinase external/internal domains

External - receptor
Internal - tyrosine kinase

28

Ras mutations

Mutations that turn Ras on will cause cancer

29

Ras causes

Proliferation, survival, and growth

30

Ras pathway

EGF binds EGFR (receptor tyrosine kinase)...recruits GRB2...Recruits SOS...Recruits Ras...Ras phosphorylates Raf...phosphorylates...MEK...Phosphorylates Erk...acts on DNA