Transcript chapter11new - Homework Market

Chapter 11
Cell Communication
PowerPoint® Lecture Presentations for
Biology
Eighth Edition
Neil Campbell and Jane Reece
Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Overview: The Cellular Internet
• Cell-to-cell communication is essential for
multicellular organisms
• What types of cell signaling have we
discussed?
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 11-4
Local Signaling
Plasma membranes
Gap junctions
between animal cells
(a) Cell junctions
(b) Cell-cell recognition
Plasmodesmata
between plant cells
Fig. 11-5ab
Local Signaling
Electrical signal
along nerve cell
triggers release of
neurotransmitter
Target cell
Secreting
cell
Local regulator
diffuses through
extracellular fluid
(a) Paracrine signaling
Neurotransmitter
diffuses across
synapse
Secretory
vesicle
Target cell
is stimulated
(b) Synaptic signaling
Fig. 11-5c
Long-Distance Signaling
Endocrine cell
Blood
vessel
Hormone travels
in bloodstream
to target cells
Target
cell
(c) Hormonal signaling
• Hormone
– Chemical signal
– Secreted into the circulatory system
– Communicates regulatory messages
• Only Target cells equipped to respond
• Hormones Regulate:
• Growth
• Development
• Reproduction
• Homeostasis
• Concept 45.2: Signal Transduction Pathways
1. RECEPTION
Hormones bind to target cell receptors
2. TRANSDUCTION
Relays signal
3. RESPONSE
Specific cell responses
Fig. 11-6-1
EXTRACELLULAR
FLUID
1 Reception
Receptor
Signaling
molecule
CYTOPLASM
Plasma membrane
Fig. 11-6-2
CYTOPLASM
EXTRACELLULAR
FLUID
Plasma membrane
1 Reception
2 Transduction
Receptor
Relay molecules in a signal transduction pathway
Signaling
molecule
Fig. 11-6-3
CYTOPLASM
EXTRACELLULAR
FLUID
Plasma membrane
1 Reception
2 Transduction
3 Response
Receptor
Activation
of cellular
response
Relay molecules in a signal transduction pathway
Signaling
molecule
• 3 major classes of molecules function as
hormones in vertebrates
– Water-soluble:
1. Proteins and peptides
2. Amines (derived from amino acids)
– Fat-soluble:
3. Steroids
Water-Soluble Hormones
Where are the
Receptors for WaterSoluble hormones
located?
=Plasma Membrane
(a) Receptor in plasma membrane
Water-Soluble Hormones
1.
1. RECEPTION=
Hormone binds to
receptor in PM
2.
2. TRANSDUCTION=
signal pathway
initiated in cytoplasm
(a) Receptor in plasma membrane
Water-Soluble Hormones
1.
3. RESPONSE
A.CYTOPLASMIC =
Protein in cytoplasm
activated
2.
-ORB. NUCLEAR =
Transcription factor in
nucleus is activated
3A.
3B.
Ex: Epinephrine- nuclear or cytoplasmic response?
Lipid-Soluble Hormones
Where are the Receptors for
Fat-Soluble hormones
located?
= In the Nucleus
1.
Lipid-Soluble Hormones
1. Hormone easily moves
through PM cytoplasm
2. RECEPTION= Hormone
binds with receptor in
nucleus
1.
2.
Lipid-Soluble Hormones
3. TRANSDUCTION=
Activated receptor binds
to DNA transcription
1.
4. RESPONSE= Protein
synthesis
2.
3.
4.
Lipid-Soluble Hormones
1. Hormone easily moves
through PM cytoplasm
1.
2. Hormone binds with
receptor in nucleus
3. Activated receptor binds
to DNA transcription
2.
3.
4. Protein synthesis
4.
Ex Fat-Soluble Hormone: Estradiol Vitellogenin
• Estradiol produced
by female birds
• Liver cells have
receptor for estradiol
• Hormome-receptor
complex binds
DNA 
vitellogenin
• Vitellogenin used to
produce egg yolk