Transcript Ch 3 Muscle and Nervous Tissue pgs. 97-100

Muscle and Nervous Tissue
Pages 97-101

Function:
◦ contract (shorten) to produce movement

Three types:
1. Skeletal muscle
2. Cardiac muscle
3. Smooth muscle
© 2015 Pearson Education, Inc.



Voluntary (consciously) control
Attach to bones or skin
Produce:
◦ gross body movements
◦ facial expressions

Cell Characteristics:
◦ Striations (stripes)
◦ Multinucleate (more than one nucleus)
◦ Long, cylindrical shape
© 2015 Pearson Education, Inc.
Figure 3.20a Type of muscle tissue and their common locations in the body.
Nuclei
Part of muscle
fiber
(a) Diagram: Skeletal muscle
Photomicrograph: Skeletal muscle (195×)




Involuntar control
only in the heart
Pumps blood through blood vessels
Characteristics of cardiac muscle cells
◦ Striations
◦ One nucleus, short, branching cells
 Look somewhat like bamboo
◦ Intercalated discs:
 Areas between cells which contain gap junctions to
connect cells together so that the impulse spreads
across the heart synchronously
© 2015 Pearson Education, Inc.
Figure 3.20b Type of muscle tissue and their common locations in the body.
Intercalated
discs
Nucleus
(b) Diagram: Cardiac muscle
Photomicrograph: Cardiac muscle (475×)
Compare the two- note the differences
Skeletal
Cardiac


Involuntary control
Location: where constricting and enlarging is required
◦ walls of hollow organs
 Peristalsis: a wavelike activity that moves digested
material through the small intestine
◦ blood vessels

Characteristics:
◦ No visible striations
◦ Single nucleus
◦ Spindle-shaped cells
© 2015 Pearson Education, Inc.
Figure 3.20c Type of muscle tissue and their common locations in the body.
Smooth
muscle cell
Nuclei
(c) Diagram: Smooth muscle
Photomicrograph: Sheet of smooth muscle (285×)

Two groups of cells:
◦ Neurons
◦ Neuroglia (glial cells)
 these insulate, protect, and support neurons

Function: receive and conduct
electrochemical impulses to and from body
parts
◦ Irritability
◦ Conductivity
© 2015 Pearson Education, Inc.
Figure 3.21 Nervous tissue.
Brain
Nuclei of
supporting
cells
Spinal
cord
Nuclei of
supporting
cells
Cell body
of neuron
Neuron
processes
Cell body
of neuron
Neuron
processes
Diagram: Nervous
tissue
Photomicrograph: Neurons (320×)