cellular communication transduction and response

Question 1

intracellular receptors are found in

Answer 1

the cytoplasm and nucleus and nucleus membrane

Question 2

for intracellular receptors how do chemical messenger pass through the cells plasma membrane

Answer 2

because they are hydrophobic and small enough to cross the hydrophobic interior of the membrane

Question 3

what signaling molecules can pass through the Plasma membrane

Answer 3

steroid and thyroid hormones (hydrophobic enough)

Nitric oxide (small enough)

Question 4

genes in a cell’s DNA function by being transcribed and processed into

Answer 4

mRNA

Question 5

once the mRNA leaves the nucleus it is

Answer 5

translated into a specific protein by ribosomes in the cytoplasm

Question 6

transcription process

Answer 6

proteins that control which genes are turned on then the genes are transcribed to mRNA

Question 7

transduction is a ______ pathway

Answer 7

multistep

Question 8

what are the benefits of a multistep pathway

Answer 8

-possibility of amplification of signal
-coordination and regulation
-fine-tuning response

Question 9

what are some signal transduction steps include

Answer 9

-activation of proteins by addition or removal of phosphate groups which will change shape
- release of other small molecules or ions that act as messenger

Question 10

signal transduction pathways 1st step

Answer 10

binding signal and receptor
it activates another molecule and another and so on

Question 11

relay molecules

Answer 11

the molecule that relays a signal from receptor to response are often proteins

Question 12

at each step in transduction what happens to the protein

Answer 12

the signal that is transduced will change into a different form (change shape)

Question 13

in signal transduction whats the most common reason for a shape change of a protein

Answer 13

phosphorylation

Question 14

what does a signal is relayed along a pathway mean

Answer 14

it means info is passed not the actual signal

Question 15

protein phosphorylation means

Answer 15

widespread cellular mechanism for regulating protien activity

Question 16

proteins kinase

Answer 16

enzyme that transfer phosphate groups from ATP to a protein (phosphorylating protein)

Question 17

the relay molecules in protein phosphorylation are called a

Answer 17

phosphorylation cascade

Question 18

in a phosphorylation cascade what happens

Answer 18

there is a shape change each time to the molecule and once a phosphate is added it can make protein inactive or active

Question 19

protein phosphatases

Answer 19

enzymes that rapidly remove p groups from proteins

Question 20

Protein dephosphorylation

Answer 20

removes p and make pk inactive

provides mechanism for turning off signal transduction pathway when initial signal is gone

Question 21

Protein dephosphorylation makes PK

Answer 21

reusable

Question 22

Activity of protein regulated by phosphorylation depends on the

Answer 22

balance in cell between active kinase molecules and active phosphatases molecules

Question 23

2nd messenger

Answer 23

small,non protein,water soluble molecules or ions in signal transduction pathway

Question 24

the 2nd messengers do what

Answer 24

readily spreads in cell by diffusion

Question 25

most common second messenger is

Answer 25

is cAMP and calcium ions

Question 26

1st messenger

Answer 26

extracellular signaling ligand that binds to membrane receptor

Question 27

many of the relay molecules in signal transduction is

Answer 27

protein kinase

Question 28

abnormal activity with the PK causes

Answer 28

cancer

Question 29

Adenylyl cyclase

Answer 29

enzymes embedded in PM converts ATP to cAMP in response to signal

Question 30

cAMP broadcasts signal to

Answer 30

cytoplasm

Question 31

what does cAMP do

Answer 31

activates protein kinase A (which phosphorylates other proteins depending on cell type)

Question 32

the increase in the 2nd messenger ca does what

Answer 32

muscle contraction,secretion,cell division

Question 33

protein pumps active transport ca ions out of cell to

Answer 33

ER