#7 Slides: Cardiac, Skeletal and Smooth Muscle
Look at a slide of Skeletal, Cardiac and Smooth muscle at 400x magnification.
Sketch each of the slides.
1. What are the differences and similarities between what you see in these 3 slides?
2. Thinking about the usages of these different muscle types what traits would be most helpful
for each of these types of tissues?
Skeletal is attached to the bones and is voluntary. Smooth is attached to the organs (stomach,
intestines, etc) and is involuntary. Cardiac is the tissue of the heart and is also involuntary.
3. Use the following flash cards to make a Venn diagram of the different tissue types.
http://quizlet.com/10464442/characteristic-of-myoblast-skeletal-smooth-and-cardiac-musclefunctions-flash-cards/
(On the right side of the screen you can change the view of the comparison from ‘list’ to ‘grid’ if
you like) You should have 5 areas of comparison. (don’t pick the ones you don’t understand)
1. Skeletal muscle
The tissue most commonly thought of as muscle is skeletal muscle. Skeletal muscles cover your
skeleton, giving your body its shape. They are attached to your skeleton by strong, springy tendons or
are directly connected to rough patches of bone. Skeletal muscles are under voluntary control, which
means you consciously control what they do.
Just about all body movement, from walking to nodding your head, is caused by skeletal muscle
contraction. Your skeletal muscles function almost continuously to maintain your posture, making one
tiny adjustment after another to keep your body upright. Skeletal muscle is also important for holding
your bones in the correct position and prevents your joints from dislocating. Some skeletal muscles in
your face are directly attached to your skin. The slightest contraction of one of these muscles changes
your facial expression. Skeletal muscle generates heat as a by-product of muscle activity. This heat is
vital for maintaining your normal body temperature.
Smooth Muscle
Smooth muscle is found in the walls of hollow organs like your intestines and stomach. They work
automatically without you being aware of them. Smooth muscles are involved in many 'housekeeping'
functions of the body. The muscular walls of your intestines contract to push food through your body.
Muscles in your bladder wall contract to expel urine from your body. Smooth muscles in a woman's
uterus (or womb) help to push babies out of the body during childbirth. The pupillary sphincter muscle
in your eye is a smooth muscle that shrinks the size of your pupil.
Cardiac Muscle
Your heart is made of cardiac muscle. This type of muscle only exists in your heart. Unlike other types
of muscle, cardiac muscle never gets tired .It also does not need nerves attached to it to work. It is
controlled by hormones and chemicals in the body such as adrenaline, that can increase or decrease
its speed. It works automatically and constantly without ever pausing to rest. Cardiac muscle contracts
to squeeze blood out of your heart, and relaxes to fill your heart with blood.