Muscular System

Muscular
System

Open Ended

Tell me everything you know or want to know about the muscular system.

More than 600 muscles make up the
system known as the muscular system .
Muscles are bundles of muscle fibers
held together by connective tissue.

The 5 main functions of the muscular system are :

●

movement

●

Support

●

Protection

●

heat generation

●

blood circulation.

Muscles move body parts by
contracting and then relaxing.
Muscles can pull bones, but they
can't push them back to the
original position. So they work in
pairs of flexors and extensors.
The flexor contracts to bend a
limb at a joint.

Muscles work with
your bones, tendons
and ligaments.
Tendons attach
skeletal muscles to
bones all over your
body. Together, they
support the weight of
your body and help
you move.

Muscle Support

Muscles in the torso protect the
internal organs at the front, sides,
and back of the body. The bones
of the spine and the ribs provide
further protection. Muscles also
protect the bones and organs by
absorbing shock and reducing
friction in the joints.

Protection

Generate Heat

Heat is a byproduct of
muscle activity. As ATP is
used to power muscles
about ¾ of its energy
escapes as heat. Skeletal
muscle is most responsible
for generating heat.

Open Ended

The next function is Circulation. How do you think the muscles help with circulation? (even if you do not know, try to make a good guess)

Skeletal muscles also play a
key role in the movement of
blood around the body. Veins
embedded within a muscle
are compressed during
contraction of that muscle,
causing an increase in blood
pressure due to the presence
of one-way valves within the
veins. This increase in
pressure drives the blood
towards the heart.

Blood Circulation

Open Ended

Let's recap: What are the 5 main functions of muscles and give an example for each.

There are 3 types of muscles:

Skeletal muscles:the muscles that connect
to your bones and allow you to perform a wide
range of movements and functions. Skeletal
muscles are voluntary, meaning you control
how and when they work.

Examples of skeletal muscles:

● shoulder muscles (help pick thing up)
● hamstring muscles (walking)
● abdominal muscles (protect the spine)

Smooth Muscles:

These muscles are involuntary,
meaning they work without
thinking about it.

Open Ended

Now that you know what smooth muscles are, can you think of any examples of smooth muscles? Please do not leave blank, make a good guess.

Examples of smooth muscles:

● Digestive tract muscles
● Respiratory muscles
● Bladder muscles

Cardiac Muscles

Cardiac muscles are also
involuntary and are found in the
heart. Cardiac muscles contract
the heart to keep blood flowing
throughout the body during its
lifetime.

Blood vessels contain only smooth muscle cells.
These muscle cells reside within the tunica media
along with elastic fibers and connective tissue.