Muscles

Interesting Muscle Facts1. Thirty facial muscles create looks like surprise, happiness,

sadness, and frowning

2. Eye muscles are the busiest muscles in the body. Scientists estimate they may move more than 100,000 times a day

3. Largest muscle in the body is the gluteus maximus muscle in the buttocks.

4. It takes 10 muscles to smile, 12 muscles to frown ... and 1 to make a difference!

5. Smallest muscle in our body is in the inner ear and is called stapes

What makes our bodies move?MUSCLES!!!

– Marionettes are puppets on strings. By pulling different strings, you make these puppets dance, bow or wave their arms. Your skeleton is similar to the puppet’s body. It does not move unless something pulls on its bones. The strings that pull on your bones are your MUSCLES.

What is Muscle?

Muscle is a tissue composed of bundles of elongated cells capable of contraction and relaxation to produce movement in an organ or body part.

Muscle Fibres

Parts of the muscleTendon: • white cord made up of

extremely strong tissues • Connects muscle to the

boneBody: • thick part of the muscle

Aponeurosis: • membrane of connective

tissue separating the muscle from the adjacent muscles

Tendon vs. Ligament

Functions of MusclesA. Movement of limbs and organs

B. Posture maintenance– Even while you are still your muscles are continuously at work in

order to maintain your posture

C. Joint stabilization– Without muscles, some of our joints would not stay in place

D. Heat Release– Muscle contraction requires chemical energy– 75% of this chemical energy is transformed into thermal energy (ie.

heat).– The thermal energy that is released helps maintain body

temperature at 37C

Your turn to figure it out!

Voluntary Movement

Voluntary Muscle

Involuntary Movement

Involuntary Muscle

A.

B.

C.

D.

Answers.

• A. Voluntary

• B. Involuntary

• C. Voluntary

• D. Involuntary

Voluntary vs. Involuntary Muscle

• Muscle can be voluntary or involuntarya) Voluntary - consciously controlled by the brain

Ex: raising your arm to scratch your head

b) Involuntary - not consciously controlled by the brain.

Ex: the contraction of the diaphragm during inhalation

There are 3 Types of Muscle

All the functions of muscle are carried out by 3 different muscle tissues:

1.Skeletal (Striated)

2.Smooth

3.Cardiac

Skeletal Muscle (voluntary -striated)

Skeletal Muscle

• Voluntary• Striated appearance• Attached to the bones of the skeleton• Can generate a lot of force but tire easily: low

endurance

Smooth Muscle (Involuntary - no striations)

Smooth Muscle

• Involuntary• No striations• Make up the walls of the internal organs such

as the bladder, stomach, and uterus.• Do not generate as much force as skeletal

muscle but do not tire easily: medium endurance

Cardiac Muscle (involuntary - striated)

Cardiac Muscle

• Involuntary• No striations• Found only in the heart• Has great strength and endurance

Antagonistic Muscles

• All muscles work in pairs. Whether they are striated muscle, smooth muscle or cardiac muscle makes no difference, all muscles must work in pairs.

Antagonistic Muscle Pair

biceps

triceps

When biceps contracts, the triceps elongates and relaxes.

When the triceps contracts the biceps elongates and relaxes.