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Muscular and Nervous Tissue
Chapter 4.3
Human Anatomy & Physiology
Muscular Tissue
• Function
• Contraction
• Attachment by
tendons to bones for
movement
• Movement: Voluntary
and involuntary
Muscular Tissue
• Appearance – striated
(striped)
– Alternating light and
dark bands
• Location – Usually
attached to skeleton
• Each cell has a
nucleus that is
centrally located
Types of Muscular Tissue
• Types
A. Skeletal
B. Smooth
C. Cardiac
Characteristics of Skeletal Muscle
• Appearance: striated
• Location: Attached
primarily to bones
• Control: Voluntary
(conscious)
• Contracts quickly, tires
easily (fatigable)
• Allows for wide range of
forces to be generated
Skeletal Muscle Tissue - 400X
Smooth Muscle
• Appearance: spindleshaped
• Location: wall of hollow
organs
– example: Intestines, urinary
bladder, ureters, urinary
bladder, blood vessels
• Control: Involuntary
• Contracts rhythmically and
quickly, tires easily
(fatigable)
• Allows for wide range of
forces to be generated
Smooth Muscle
Smooth Muscle Tissue - 400X
Cardiac Muscle
• Has features of both skeletal and smooth muscle
- Strong contractions and striated appearance is
similar to skeletal muscle
- Involuntary control and rhythmic contraction is
similar to smooth muscle
• Appearance: striated
and branched (like
skeletal muscle)
• Location: heart
• Function: contraction
of heart pumps blood
and causes the
heartbeat
• Control: Involuntary
(like smooth muscle)
Cardiac Muscle Tissue - 400X
Nervous Tissue
• The ultimate control of all the organ
systems is done by the nervous system.
– The nervous system controls and coordinates
functions throughout the body and responds
to internal and external stimuli.
Nervous Tissue
• Found: brain, spinal
cord, has specialized
cells
• The cells that transmit
these impulses are
called neurons.
Structure of a Neuron
Nucleus
Dendrites
Axon
terminals
Cell body
Myelin sheath
Nodes
Axon
Neuron Structure
• The largest part of a typical neuron is the
cell body.
• It contains the nucleus and much of the
cytoplasm.
Neuron Structure
• Dendrites extend from the cell body and
carry impulses from the environment
toward the cell body.
Neuron Structure
• The axon is the long fiber that carries
impulses away from the cell body.
Neuron Structure
• The axon is sometimes surrounded by an
insulating membrane called the myelin
sheath.
Neuron Structure
There are gaps in the myelin sheath, called
nodes, where the membrane is exposed.
• Impulses jump from one node to the next.