Chapter 11

Question 1

hormones

Answer 1

chemicals for long-distance signaling in animals and plants

Question 2

paracrine signaling

Answer 2

local signaling in animals from a single cell in the vicinity

Question 3

synaptic signaling

Answer 3

travels across the synapse between animal nerve cells

Question 4

endocrine signaling

Answer 4

signaling by hormones

Question 5

reception

Answer 5

1st part of cell signaling; target cell’s detection of a signaling molecule coming from outside the cell

Question 6

transduction

Answer 6

2nd part of cell signaling; converts the signal to a form that can bring about a specific cellular response

Question 7

signal transduction pathway

Answer 7

sequence of changes in a series of different molecules

Question 8

response

Answer 8

3rd part of cell signaling; transduced signal finally triggers a specific cellular response

Question 9

ligand

Answer 9

a molecule that specifically binds to another molecule, often a larger one

Question 10

G protein-coupled receptor (GPCRs)

Answer 10

a cell-surface transmembrane receptor that works with the help of a G protein

Question 11

G protein

Answer 11

protein that binds the energy-rich molecule GTP

Question 12

protein kinase

Answer 12

enzyme that transfers phosphate groups from ATP to a protein

Question 13

phosphorylation cascade

Answer 13

series of protein phosphorylations occurring sequentially in which each protein activates/phosphorylates the next

Question 14

protein phosphates

Answer 14

enzymes that can rapidly remove phosphate groups from proteins

Question 15

second messengers

Answer 15

small, non-protein, water-soluble molecules or ions

Question 16

cyclic AMP/cAMP

Answer 16

cyclic adenosine monophosphate, made from ATP, common second messenger in eukaryotes

Question 17

adenylyl cyclase

Answer 17

enzyme embedded in the plasma membrane that converts ATP to cAMP

Question 18

inositol trisphosphate (IP3)

Answer 18

second messenger that stimulates release of calcium from the ER

Question 19

deacylglycerol (DAG)

Answer 19

second messenger

Question 20

scaffolding proteins

Answer 20

large relay proteins to which several other relay proteins are simultaneously attached

Question 21

apoptosis

Answer 21

type of programmed cell death, brought about by activation of enzymes that break down chemical parts of the cell

Question 22

signal transduction pathway

Answer 22

series of steps linking mechanical, chemical, or electromagnetic stimulus to a specific cellular response

Question 23

receptor tyrosine kinases (RTKs)

Answer 23

receptor protein that spans the membrane, catalyzes the transfer of phosphate group from ATP to a tyrosine

Question 24

ligand-gated ion channel

Answer 24

transmembrane protein containing a pore that opens or closes as it changes shape in response to a ligand