Chapter 11 - Cell Communication

Front 1

Signal transduction pathway

Back 1

the process by which a signal on a cell's surface is converted into a specific cellular response

Front 2

Local regulator

Back 2

a substance that influences cells in the vicinity of the releasing cell;
e.g., growth factor or neurotransmitter

Front 3

Hormones

Back 3

chemicals that are used to to influence cells in other, more distant, areas of the body

Front 4

G-protein linked receptor

Back 4

a plasma membrane receptor that works with the help of a protein called a G protein;
contain seven alpha-helices spanning the membrane

Front 5

G protein

Back 5

part of the G-protein linked receptor that functions as a switch that is on or off depending on which of two guanine nucleotides is attached, GDP (inactive) or GTP (active)

Front 6

Tyrosine kinase

Back 6

part of the receptor protein on the cytoplasmic side of the membrane that functions like an enzyme;
catalyzes the transfer of phosphate groups from ATP to the amino acid tyrosine on a substrate protein

Front 7

Tyrosine-kinase receptors

Back 7

membrane receptors that attach phosphates to protein tyrosines

Front 8

Ligand-gated ion channels

Back 8

protein pores in the plasma membrane that open or close in response to a chemical signal, allowing or blocking the flow of specific ions, such as Na+ or Ca++

Front 9

Protein kinase

Back 9

the general name for an enzyme that transfers phosphate groups from ATP to a protein

Front 10

Protein phosphatases

Back 10

enzymes that remove phosphate groups from proteins

Front 11

Second messengers

Back 11

small, nonprotein, water-soluble molecules or ions;
small size facillitates the diffusion of second messenger throughout the cell;
cAMP and Ca++ are most common

Front 12

cyclic AMP

Back 12

a common second messenger

Front 13

Adenylyl cyclase

Back 13

an enzyme built into the plasma membrane of a cell that converts ATP to cAMP in resposne to an extracellular signal

Front 14

Diacylglycerol (DAG)
Inositol trisphosphate (IP3)

Back 14

two messengers produced by cleavage of a certain kind of phospholipid in the plasma membrane;
stimulates the release of Ca++ from the ER in

Front 15

Calmodulin

Back 15

a Ca++ binding protein present at high levels in eukaryotic cells that mediates many calcium-regulated processes in cells;
Ca++ binds to calmodulin, causing it to change its configuration and act on other proteins