Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cell Biology And Signaling > Intracellular Signalling > Flashcards

Intracellular Signalling Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Definition of endocrine

A

Signal produced by cells in 1 body part, travels in blood to target cells elsewhere

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

Definition of autocrine

A

Signal acts on same cell that produces it

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

Definition of paracrine

A

Signal produced by cell, acts on cells close by

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

Definition of contact dependent

A

Signal is integral part of 1 cell, interacts directly with another cell

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

Definition of neuronal

A

Electrical signal transmitted down cell, message passed to another via synapse

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

Definition of G proteins

A

Guanine nucleotide binding proteins act as molecular switches inside cells. Involved in transmitting signals

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

Function of cellular responses

A

Change metabolic activités
Secrete and release
Changes in gene expression
Sensory perception

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

Factors that act as extracellular signals

A 
Amino acids + derivatives
Steroids
Prostaglandins (eicosanoids)
Proteins and peptides
Gases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How cells signal to each other

A 
Endocrine
Autocrine
Paracrine
Contact dependent
Neuronal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Characteristics of receptors/signals

A

Receptor must be expressed in order to respond to signal
High selectivity and affinity
Signal can bind to different receptor types
Signal eventually turned off

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

Location of receptors

A

Cell surface

Intracellular receptors

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

What happens with a receptor on the cell surface

A

Hydrophilic hormone

Binding triggers internal response without hormone entering

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

What happens with an intracellular receptor

A

Hydrophobic hormone
Binds to internal receptor, triggers internal response
Crosses plasma membrane

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

Types of signalling

A

Binding of signal to receptor by
Depolarization of signal to receptor due to ion flow
Direct transcription factor activation
Generation of 2ndary message in cell
Direct activation of enzymatic kinase cascade

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

What happens in depolarization of membrane due to ion flow?

A

Ach (signal) binds to nicotinic acetylcholine receptor

Ion channel opes to allow Na+, K+, Ca2+ in

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

What do steroid hormones have?

A

Hormone binding domains
DNA binding domain
Interacting with other transcription factors domain

17
Q

What happens in direct activation of transcription factors

A

Binding of steroid induces conformational change, allows DNA binding, activation of target gene transcription
DNA binding domain is sequence specific
Transcription factors = ligand dependent

18
Q

What is the secondary messenger model

A

Signal binds to transmembrane receptor (1st messenger)

Triggers other molecules in the cell, (acts as 2nd messenger)

19
Q

Structure of guanine nucleotide binding proteins

A

Inactive state, aby
Dissociates into a by when GDP binds
Free active a subunit activates effector enzymes

20
Q

Location of the G protein coupled receptor

A

Transmembrane a helix with 7 proteins

21
Q

GPCR signalling to effector enzymes

A

Signal binds to receptor
G protein (GDP bound) associates w receptor
GTP/GDP exchange on G protein (GTP bound)
G proteins dissociate into a (GTP bound) and by subunits
a (GTP bound activates effector enzyme
Effector produces 2nd messenger
GTP hydrolyses to GDP, G proteins complex reassociates, end of signal

22
Q

Structure of cAMP dependent protein kinase A (PKA)

A

Tetrameric enzyme, 2 regulatory, 2 catalytic subunits (r2c2)

When cAMP binds to both r, activates c subunits

23
Q

How does CREB affect gene transcription?

A

PKA phosphorylates cAMP response element binding protein (CREB)
CREB binds to specific sequences in target genes, transcription stimulated
Gene expression can change if change is long term (starvation)

24
Q

GPCR and IP3/DAG signalling

A

Signal molecule activates GPCR
Activated G protein a subunit activates phospholipase C
Activated phospholipase C cleaves IP3 from DAG
IP3 activates Ca2+ channel
DAG + Ca2+ activates PKC

25
Q

Direct activation of enzymatic kinase cascade

A

Binding of EGF => dimerisation of intracellular domains => autophosphorylation of tyrosines

Tyr <= SH2 <= GRB2 <= SOS

Ras is broken down from GDP => GTP and triggers MAPKKK cascade

26
Q

Ras

A

Monomeric G protein
GTP-Ras triggers kinase cascade
Has no 2ndary messenger
GDP-Ras => GTP-Ras

27
Q

What is the Ras-MAP-kinase pathway

A

Mitogen activated protein kinase kinase kinase (MAPKKK) activates MAPKK
Activates MAPK
Activates transcription factor

28
Q

GPCR and cAMP pathway

A

Molecule binds to extracellular binding GCPR site
Dissociated GTPa unit activates adenylyl cyclase
AC converts ATP => cAMP
cAMP activates PKA
PKA can activate CREB which affects transcription

Cell Biology And Signaling (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions