Ch 7 - Cell Signaling And Communication

Front 1

What can be a signal?

Back 1

A signal can be

-chemical signal

-physical stimulus

Can come from outside organism, or from neighboring cells.

To reapond to a signal, a cell must have a specific receptor that can detect it.

Front 2

Signal Transduction Pathway

Back 2

A Signal Transduction Pathway is the sequence of molecular events and chemical reactions that lead to a cell's response to a signal.

Signal transduction- a molecule touching a signal receptor.

Front 3

What are the three necessary components for a complete

Signal Transduction Pathway?

Back 3

1. Signal

2. Receptor

3. Response

Front 4

Autocrine

Back 4

Autocrine- the signal affects the cell(s) that made them. (Receptor is on same cell that sent signal)

Front 5

Autocrine

Back 5

Autocrine- the signal affects the cell(s) that made them. (Receptor is on same cell that sent signal)

Front 6

Paracrine

Back 6

Paracrine- signals affect nearby cells.

Eg- hormones travel to distant cells, usually via circulatory system.

Front 7

What does the term "ase" mean with regards to enzymes and signals?

Back 7

All enzymes end in the term 'ase'.

Lactase-enzyme that bonds to lactose.

Sucrase- enzyme " " " to sucrose.

L

Front 8

What does the term "ase" mean with regards to enzymes and signals?

Back 8

All enzymes end in the term 'ase'.

Lactase-enzyme that bonds to lactose.

Sucrase- enzyme " " " to sucrose.

L

Front 9

Kinase and Phosphatase

Back 9

Kinase- sole job is to put a phosphate on a molecule. To mark it, or to wake it up. Activate it.

Phosphatase- sole job is to remove a phosphate from a molecule.

Front 10

Ligand

Back 10

Receptor proteins have very specific binding sites for chemical signal molecules, or ligands.

-binding the ligand causes receptor protein to change shape.

-the binding is reversible and the ligand is not altered.

Front 11

Effects of a signal

Back 11

-opening ion channels

-changing enzyme activity

-differential gene transcription

-opening ion channels is a key step in response of nervous system cells

(ex: the sense of smell)

Oderant molecules bind to receptors in the nose, and a G protein is activated.

Front 12

Cell Junctions - Gap Junctions

Back 12

Multicellular organisms have cell junctions that allow communication.

Gap Junctions in animals.

Front 13

Cell Junctions - Plasmodesmata

Back 13

Multicellular organisms have cell junctions that allow communication.

Plasmodesmata in animals.

Front 14

Kinase

Back 14

In biochemistry, a kinase is a type of enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates.