Cell Communication

Question 1

Molecules secreted by cells to hit receptors

Answer 1

ligand
Cytokine – Immune system
Neurotransmitter – nervous system


Question 2

Communication between different cells

Answer 2

Intracellular signaling

Question 3

Communication within one cell

Answer 3

Intercellular signaling

Question 4

Cells that release chemical signals or ligands

Answer 4

Signaling cells

Question 5

Molecule that binds to another specific molecule

Answer 5

Ligand

Question 6

Protein that ligand is intended to bind to in or on a cell

Answer 6

Receptor

Question 7

Cell intended to receive ligand via receptor

Answer 7

Target cell

Question 8

Autocrine signaling

Answer 8

Cell targets itself

Question 9

Direct contact

Answer 9

Ligand binds to receptor on adjacent cell through gap junction. Ex. Intestines and plants

Question 10

Paracrine signaling

Answer 10

Ligands bind to nearby cells. Typically target adjacent cells. Diffusion through ECM

Question 11

Endocrine signaling

Answer 11

Ligands Target distant cells and are transported via bloodstream. Receptors determine target cells from not target cells

Question 12

Synaptic signaling

Answer 12

Paracrine signaling where nerve cells release neurotransmitters which bind to receptors on nearby nerve or muscle cells

Question 13

What do insecticides affect?

Answer 13

Inhibit synapse receptors from accepting acetylcholine

Question 14

What kind of response does a cell have when the ligand binds to the receptor?

Answer 14

Chemical response

Question 15

Series of chemical reactions after ligand binds to a receptor

Answer 15

Signal transduction

Question 16

Signal transduction includes

Answer 16

Activating or inactivating proteins
 different cells react differently to same ligand

Question 17

Phosphorylation

Answer 17

Add phosphate via kinase to activate

Question 18

Kinase enzyme receptor

Answer 18

Receptor tyrosine kinase. Receptor is dimerized and autophosphorylated. Phosphate is added to tyrosine on response protein. Receptors move closer as phosphate is added. ex. Epidermal growth factor receptor – wound healing

Question 19

Dephosphorylation

Answer 19

Phosphatase enzyme removes phosphate from proteins and deactivates it

Question 20

Integral protein receptors have ______ hydrophobic domains

Answer 20

7

Question 21

Two locations for integral protein receptors

Answer 21

1) Cell surface/transmembrane (cell specific protein markers) - plasma membrane: signal transduction
2) intracellular/internal/cytoplasmic - inside cell: Respond to hydrophobic ligands. Regulate transcription

Question 22

Three classes/categories of receptors

Answer 22

1) Ion channel linked/gated receptors
2) enzymatic receptors
3) G protein coupled receptors

Question 23

Selective ion channels open in response to ligand binding. Contain many hydrophobic amino acid

Answer 23

Ion channel linked/gated receptor

Question 24

Receptor is an enzyme or is associated with an enzyme. Enzyme is activated when ligand binds. Both extracellular and intracellular domains

Answer 24

Enzymatic receptors

Question 25

Receptors on G protein on guanine triphosphate . G protein activates effector protein (enzyme) When ligand binds, G protein releases a second messenger to generate cellular response

Answer 25

G protein coupled receptors

Question 26

Steroid hormones

Answer 26

Nonpolar (fat soluble): cross the plasma membrane to reach steroid receptor
Regulate gene expression: Inhibitor block steroid receptor from binding to DNA till hormone moan

Question 27

Three domains on Intracellular receptor

Answer 27

Hormone binding
DNA binding
Call activators binding to affect gene expression

Question 28

Small molecules produced by bacteria to regulate gene expression

Answer 28

Autoinducers