muscular system unit f
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Muscular System Unit F. 1H06.01. Describe the structure of the muscles. Nearly half our weight comes from muscle tissue. There are 650 different muscles in the human body. Muscles give us shape, posture, movement and form. Muscles produce most of our body heat. Muscular System. - PowerPoint PPT PresentationTRANSCRIPT
Muscular SystemUnit F
1H06.01
Describe the structure of the muscles.
Muscular System Nearly half our
weight comes from muscle tissue.
There are 650 different muscles in the human body.
Muscles give us shape, posture, movement and form.
Muscles produce most of our body heat.
Types of MusclesSkeletal muscle Attached to bone. Striated (striped)
appearance. Voluntary. Multinucleated muscle cell
bundles (muscle cells = muscle fibers).
Sarcolemma = cell membrane.
Contract quickly, fatigue easily, can’t maintain contraction or long period of time.
Types of Muscles Cont.Smooth muscle. Visceral (organ) muscle. Found in walls of digestive
system, uterus and blood vessels.
Cells small and spindle-shaped.
Involuntary. Controlled by autonomic
nervous system. Act slowly, do not tire easily,
can remain contracted for long time.
Types of Muscle Cont.Cardiac muscle. Found only in the
heart. Striated and
branched. Involuntary. Cells are fused-
when one contracts, they all contract.
Muscle Anatomy
1H06.02 Analyze the function of the
muscular system
Characteristics of Muscles When a
muscle becomes shorter, thicker & causes movement, it is said to have?
CONTRACTIBILITY
Excitability (irritability)- the ability to respond to certain stimuli by producing impulses.
Extensibility- the ability to be stretched.
Elasticity- ability of muscle to return to its original length when relaxing.
Movement
As a muscle contracts, it pulls the insertion bone closer to the origin bone. Movement occurs at the joint between the origin and the insertion.Rule: A muscle’s insertion bone moves toward its origin bone.
1.Muscles move bones by pulling on them.
2. Groups of muscles usually contract to produce a single movement.
Movement Cont. Motor unit- a motor neuron
plus all the muscle fibers it stimulates.
Muscle Fatigue Muscle fatigue-
caused by the accumulation of lactic acid in the muscles.
Neuromuscular Junction Neuromuscular junction- the junction
between the motor neuron’s fiber which transmits the impulse-and the muscle cell membrane.
AcetylcholineIs a chemical neurotransmitter, diffuses across
the synaptic cleft
(carries impulse across synaptic cleft).
If a muscle cell is stimulated repeatedly without rest it
losses its ability to contract! This is called?
What thoracic muscle aids in breathing?
Muscles that are partially contracted at all times are
said to be in a constant state of what?
1H06.03 Identify characteristics &
treatment of common muscle disorders.
Disorders and Related Terminology
Atrophy- wasting away of
muscles.Massaging the muscle
helps atrophy.Failing to exercise can
makemuscles weak, flaccid
& cause them to
atrophy.
Myalgia- muscle pain.
Tendonitis- inflammation of a tendon.
Strain- tear in the muscle resulting
from excessive use. Bleeding inside
the muscle can result in considerable
amount of pain & swelling. Ice packs
will help stop the bleeding and
reduce swelling.
Sprain-stretched ligament
Hypertrophy- an increase in the size of the muscle cell.
A person who lifts weights &
overuses his muscles will
enlarge their size.
Muscle spasm (cramp)- sustained
contraction of the muscle, usually
because of overuse. Severe calf pain at
night is caused by muscle spasms.
Sphincter Special circular
muscles in openings of esophagus and stomach, stomach and small intestine, anus, urethra and mouth.
What muscle is found in the neck?
Major muscle that lies over the upper ribs?
Muscle that abducts the upper arm at the shoulder
joint?
Medical name for the calf muscle?
Circular muscles in the openings between the
esophagus & stomach are?
The main muscle in the lower back is the?
The main muscle of the upper back is the?
What muscle is found in the arm?
What muscle is considered VOLUNTARY?
Which kind of muscle forms the walls of the heart?
Joanie is experiencing oxygen dept. What has he
been doing?Oxygen debt- after exercise,
the amount of oxygen needed
by the muscle to change lactic
acid back to glucose.
If you want to improve your extensibility you should do
what every morning?