Fundamentals of Anatomy and Physiology

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Endocrine System
●● Growth hormone from the anterior pituitary gland

stimulates muscular development.^
●● Hormones increase blood flow to muscles during
exercise.

Cardiovascular System
●● The heart pumps blood to the muscle cells, carrying

nutrients to and wastes away from the muscle cells.^
●● Red blood cells carry oxygen to and carbon dioxide
gas away from the muscle cells.

Lymphatic System
●● Skeletal muscle contractions push lymph through
the lymphatic vessels, particularly by the action of

breathing.^
●● Lymphocytes combat infection in the muscles and
develop immunities.

Digestive System
●● Skeletal muscle contraction in swallowing brings food
to the system; smooth muscle contraction pushes di-

gested food through the stomach and intestines.^
●● The intestines absorb digested nutrients to make them
available to muscle cells for their energy source.

Respiratory System
●● Breathing depends on the diaphragm and intercos-tals

muscles.^
●● The lungs provide oxygen for muscle cells and
-eliminate the carbon dioxide waste from cellular
respiration.

Urinary System
●● Smooth muscles push urine from the kidneys down
the ureters to the bladder.^
●● Skeletal muscles control urine elimination.
●● In the loop of Henle in the nephrons of the kidneys,
calcium levels are controlled by eliminating any
excess or restoring needed calcium to the blood for
muscle contraction.

Reproductive System
●● Skeletal muscles are involved in kissing, erections,
transferring sperm from the male to the female, and

other forms of sexual behavior and activity.^
●● Smooth muscle contractions in the uterus bring
about delivery of the newborn.

Chapter 9

Summary Outline

Introduction

1. Skeletal muscles help us read by moving our
   eyes, allow us to move in our environment and
   breathe.^


2. Smooth muscles push food through our intestines,
   contain blood in our arteries and veins, and push
   urine down our ureters.^


3. Cardiac muscle pumps blood through our heart and
   blood vessels and maintains blood pressure.^


4. Muscles make up 40% to 50% of our body weight.

The Types of Muscle

The three types of muscle tissue are skeletal, smooth or

visceral, and cardiac.

1. Skeletal muscle cells are voluntary, striated, and
   multinucleated cells that are much longer than their
   width, hence are also called muscle fibers.^


2. Smooth muscle cells are involuntary (we cannot
   control them at will), nonstriated, and uninucleated
   fibers.^


3. Cardiac muscle cells are also involuntary but
   are striated and uninucleated. These cells do
   not look like fibers but have extensions or
   branches.

The Anatomy of Skeletal or

Striated Muscle

1. The skeletal muscle cell or fiber is surrounded by
   an electrically polarized cell membrane called a
   sarcolemma.^


2. A muscle actually consists of a number of skeletal
   muscle bundles called fasciculi. Each bundle or
   fascicle- is composed of a number of muscle fibers
   or cells.^


3. Each muscle cell in a fascicle is surrounded by
   delicate- connective tissue called the endomysium.^


4. Each bundle or fascicle is surrounded with another
   layer of connective tissue called the perimysium.^


5. The perimysium of each fascicle is covered with
   another layer of connective tissue surrounding the
   whole muscle called the epimysium.