The Musculoskeletal System

04/21/23 1

http://www.youtube.com/watch?v=C2dTbJDQ3u0

The Musculoskeletal System

• The organs of the musculoskeletal system are the bones and skeletal muscle.

• It supports the body, protects delicate organs, and makes movement possible.

04/21/23 2

Structural features of the Skeleton

• There are three types of connective tissue in the skeleton– Bones– Cartilage– Ligaments

04/21/23 3

Bones

• Bone tissue is hard and dense. • It consists of bone cells within a matrix of

minerals and collagen fiber.• Canals inside the bones contain nerves and

blood vessels.• Only a small percentage of bone tissue is

actually living.

04/21/23 4

• Bones provide structure & support for body.• Some bones protect soft internal organs.• Bones store calcium and other minerals

needed by body.• Some bones contain marrow which produces

red and white blood cells.

04/21/23 5

Ligaments•Ligaments hold the bones together at the joints.•They are tough but elastic connective tissues.•Made of long fibers of collagen.Cartilage•Made up of special cells in a matrix of collagen fibers•Provides a strong, flexible, low-friction support for bones and other tissues.

04/21/23 6

04/21/23 7

About how many

muscles do you think the human body

has?

Answer = 650

Where do we have muscles?

04/21/23 8

We have muscles all over our body! Face

TongueEyes

Legs

ArmsHeart

HandsEars

NeckStomach

How many muscles do you think are in our face

and neck?

04/21/23 9

Our face and neck contain about one-fourth of the muscles in our

body.

That is about 162 muscles.

•

04/21/23 10

Muscles are made of hundreds of tiny fibers that contain specialized protein.

What do muscles need?• Muscles need oxygen in order to work

properly. • When they do not get enough oxygen,

they can get sore or cramp up. • When the muscles in your heart do not

get enough oxygen, you can have a heart attack.

• Can you find a link between musculoskeletal system and other organ systems?

04/21/23 11

How do muscles move our bones?

Do muscles pull or push our bones?

04/21/23 12

Muscles pull in order to make our bones move.

Our muscles usually work in pairs.

One muscle contracts (pulls) while the opposite muscle relaxes

When your arm is straight:

04/21/23 13

•Your bicep is relaxed

•Your tricep is contracted

When your arm is bent:

04/21/23 14

•Your bicep is contracted

•Your tricep is relaxed

3 Types of muscles

04/21/23 15

There are three different types of muscle in our body.

1. Skeletal muscles

2. Smooth muscles

3. Cardiac muscles

Skeletal muscles

04/21/23 16

•Are voluntary muscles that move bones.

•Are attached to tendons, which are attached to bones.

Cardiac Muscle

04/21/23 17

A special kind of involuntary muscle that makes up the heart.

The muscles in the heart contract in order to pump the blood through your body.

If your muscle stops pumping the blood, you have a heart attack.

Smooth Muscles

04/21/23 18

Are involuntary muscles that make up the blood vessels, stomach, intestines, and other organs

We can not control our smooth muscles

Examples:

•Bladder

•Uterus

•Esophagus

What happens when we do not use our muscles?

04/21/23 19

Our muscles get smaller, which makes them weak.

Can you think of some examples of when this may happen?

Problems with the Musculoskeletal System

Many, such as:•Osteoporosis•Rheumatoid arthritis•Arthritis,…

04/21/23 20

Homework:

Read 3.8 and answer questions 1-6

04/21/23 21