Cell Communication

Page
2

In long-distance signaling, plants and animals use chemicals called hormones

Slide 11

Fig. 11-5

Local signaling

Target cell

Secreting

cell

Secretory

vesicle

Local regulator

diffuses through

extracellular fluid

(a) Paracrine signaling

(b) Synaptic signaling

Target cell

is stimulated

Neurotransmitter

diffuses across

synapse

Electrical signal

along nerve cell

triggers release of

neurotransmitter

Long-distance signaling

Endocrine cell

Blood

vessel

Hormone travels

in bloodstream

to target cells

Target

cell

(c) Hormonal signaling

Slide 12

Fig. 11-5ab

Local signaling

Target cell

Secretory

vesicle

Secreting

cell

Local regulator

diffuses through

extracellular fluid

(a) Paracrine signaling

(b) Synaptic signaling

Target cell

is stimulated

Neurotransmitter

diffuses across

synapse

Electrical signal

along nerve cell

triggers release of

neurotransmitter

Slide 13

Fig. 11-5c

Long-distance signaling

Endocrine cell

Blood

vessel

Hormone travels

in bloodstream

to target cells

Target

cell

(c) Hormonal signaling

Slide 14

The Three Stages of Cell Signaling: A Preview

Earl W. Sutherland discovered how the hormone epinephrine acts on cells

Sutherland suggested that cells receiving signals went through three processes:

Reception

Transduction

Response

Animation: Overview of Cell Signaling

Slide 15

Fig. 11-6-1

Reception

1

EXTRACELLULAR

FLUID

Signaling

molecule

Plasma membrane

CYTOPLASM

1

Receptor

Slide 16

Fig. 11-6-2

1

EXTRACELLULAR

FLUID

Signaling

molecule

Plasma membrane

CYTOPLASM

Transduction

2

Relay molecules in a signal transduction pathway

Reception

1

Receptor

Slide 17

Fig. 11-6-3

EXTRACELLULAR

FLUID

Plasma membrane

CYTOPLASM

Receptor

Signaling

molecule

Relay molecules in a signal transduction pathway

Activation

of cellular

response

Transduction

Response

2

3

Reception

1

Slide 18