Cell Communication

Question 1

Local signalling

Answer 1

Signalling to nearby targets

Question 2

Long distance signalling

Answer 2

Signalling from a distance

Question 3

Signalling steps

Answer 3

1. Reception
2. Transduction
3. Response

Question 4

Reception function

Answer 4

Ligand bonds to receptor to change its shape /chemical state to activate reactions

Question 5

Transduction function

Answer 5

Receptor activates a protien causing a relay of changes

Question 6

Response function

Answer 6

Cellular response activated

Question 7

Receptor relationship with ligands

Answer 7

Lock n key reception - Receptors can bind to mulitple ligands

Question 8

Ligand

Answer 8

Signal protien

Question 9

Intercellular receptor

Answer 9

Primary messenger that’s hydrophobic and small to enter the cell

Question 10

Membrane bound/cell surface receptor

Answer 10

Large primary receptor that’s hydrophilic

Question 11

G Protien coupled receptor

Answer 11

Trasnmembrane protien that passes through the plasma membrane 7 times for development and sensory reception

Question 12

G protiens

Answer 12

Molecular switch that’s active when bonded to GTP and inactive when bonded to GDP

Question 13

GCPR relationship with G protiens

Answer 13

Ligand bound GCPR binds to GTP bound G protien which changes the G protien shape

Question 14

Activated G protien with enzymes

Answer 14

G protien binds to activate an enzyme to elicit a cellular response and then cleaves GTP for GDP

Question 15

Receptors

Answer 15

Protiens that respond and bind to specific ligands

Question 16

Ion channels

Answer 16

Membrane protiens where ions travel opens and closes as receptor changes shape

Question 17

What role does Ca2+ and Na+ have

Answer 17

Ions that pass through ion channels

Question 18

Ion channel recptors

Answer 18

Membrane protiens where ions travel in response to ligand binding

Question 19

Ligand gated ion channel step process

Answer 19

1. Ligand is unbound and gate is closed
2. Ligand binds to a receptor and gates open for ions to flow through
3. Ligand cleaves from receptor and gate closes

Question 20

Signal transduction pathway

Answer 20

Signals are relayed from receptors to target molecules via a cascade of molecular interactions

Question 21

Protien kinase role

Answer 21

Enzymes that transfer phosphates from ATP into another protien to activate it

Question 22

Dephosphorylation

Answer 22

Removing phosphates from protiens to unactivate them to remain in active state only when necessary

Question 23

Photophatase

Answer 23

Enzyme that dephosphorylates protiens

Question 24

Second messengers

Answer 24

Small molecules within the cascade

Question 25

cAMP

Answer 25

Second messenger that activates downstream protiens which starts phosphorylation cascade

Question 26

Calcium

Answer 26

Second messenger

Question 27

IP3

Answer 27

Second messenger

Question 28

IP3 and GPCR signalling

Answer 28

IP3 interacts with IP3 gated calcium channel to open the gate for calcium to flow from endoplasmic reticullum and activate protiens

Question 29

Phospholipase C function

Answer 29

Protien that cleaves PIP2 (Phospholipid) into DAG and IP3 during GPCR signalling

Question 30

Which protien dephosphoralates protiens

Answer 30

Photophatase

Question 31

Why so many steps - 4 reasons

Answer 31

1. Amplify response
2. Provide multiple opportunities for control points
3. Allows temporal and spatial control
4. Co-ordination with other signalling paths

Question 32

Receptor deception

Answer 32

Viruses imitate lock n key function to bind to receptors

Question 33

Adrenalin stimulation of glycogen breakdown

Answer 33

Massive amplification via mulitple reactions - cascades

Question 34

Glycogen

Answer 34

Stored form of glucose in liver