9.1 Signaling Molecules and Cellular Receptors

Question 1

intercellular signaling

Answer 1

Communication between cells

Question 2

intracellular signaling

Answer 2

communication within a cell

Question 3

signaling cells

Answer 3

release chemical signals in the form of small molecules (ligands)

Question 4

ligand

Answer 4

molecule that binds another specific molecule, in some cases, delivering a signal
in the process

Question 5

target cells

Answer 5

cells that are affected by chemical signals
A.K.A. receptors

Question 6

paracrine signals

Answer 6

Signals that act locally between cells that are close together

Question 7

synaptic signal

Answer 7

chemical signal that travels between nerve cells.

Question 8

neurotransmitters

Answer 8

chemical ligand that carries a signal
from one nerve cell to the next

Question 9

chemical synapses

Answer 9

small space between axon terminals and
dendrites of nerve cells where neurotransmitters
function

Question 10

endocrine signals

Answer 10

Signals from distant cells

Question 11

endocrine cells

Answer 11

origin of endocrine signals
(thyroid gland, the hypothalamus, and the pituitary gland)

Question 12

Autocrine signals

Answer 12

produced by signaling cells that can also bind to the ligand that is released (message to itself)

Question 13

intracellular mediators

Answer 13

(also, second messenger) small
molecule that transmits signals within a cell

Question 14

Internal receptors

Answer 14

found in the cytoplasm of the cell and respond to hydrophobic ligand molecules that are able to travel across the plasma membrane.

Question 15

Cell-surface receptors

Answer 15

cell-surface protein that transmits a
signal from the exterior of the cell to the interior, even though the ligand does not enter the cell

Question 16

Ion channel-linked receptors

Answer 16

bind a ligand and open a channel through the membrane that allows specific ions to pass through.

Question 17

G-protein-linked receptors

Answer 17

s bind a ligand and activate a membrane protein called a G-protein

Question 18

Enzyme-linked receptors

Answer 18

cell-surface receptors with intracellular domains that are associated with an enzyme.