The Muscular System

The Muscular System

Main functions of the Muscular System:

• Allows movements in the body

• Maintains posture

• Stabilizes joints

• Generates heat

Open Ended

How would our life be different if we lacked our muscular system?

Do you think we would be able to survive?

Properties of Muscles

-Excitable or Irritable: capable of receiving and responding to stimulations by nerves. Example A

-Contractible: capable of shortening. Example B

-Extensible: can be stretched without damage. Example C

-Elasticity: able to return to resting shape after being contracted or extended. Example D

-Adaptability: can change in response to how it's being used, get bigger or smaller. Example E

Multiple Select

What are the main functions of the muscular system? Click all that apply

• Muscles make you look good

• Muscles make you look worse

• Muscles help you move

• Muscles help maintain your posture

Muscle Movement

• Involuntary Movement: controlled by the unconscious part of the brain. (Examples: speaking, walking, writing

• Voluntary: controlled consciously by a person. (Examples: heartbeat, intestine moving waste, breathing)

Open Ended

Think About It!

In the last 30 minutes, which of your movements have been voluntary?

Which movements have been involuntary?

Types of Muscles:

• Cardiac: form the wall of the heart and controls your heartbeat

• Smooth: weakest of all muscle tissues found in organ and perform unique functions like grinding, churning, or moving

• Skeletal: connect to the skeleton in at least one place to move parts of bones closer to each other

How do muscles get their names?

1. Location of the muscle

-Named for the structure near which the muscle is found.

Example: muscle near the Tibia = Tibialis anterior

2. Size of Muscles

• Maximus = largest (ex. gluteus maximus)

• Medius = medium (ex. gluteus medius)

• Major – larger of a pair

• Minor – smaller of a pair

3. Direction of Muscle

• Rectus- muscle fibers run parallel to midline

• Transverse- muscle fibers run perpendicular to midline

• Oblique- muscle fibers run diagonal to midline

4. Number of Origins (tendons attached to the muscle)

• Biceps= two

• Triceps= three

• Quadriceps= four

5. Shape of the Muscle

• Deltoid- having a triangular shape

• Trapezius- having a trapezoid shape

• Rhomboideus- having a diamond shape

• Serratus- having a saw-toothed shape

• Orbicularis – circular

Serratus Anterior

Multiple Choice

Which of these is NOT a way muscles get named?

• Shape

• Location

• Amount of tendons attached

• Elasticity or stretchiness

What are muscles made of?

Muscles are all made of the same type of tough and elastic tissue (sort of like the material in rubber bands). Muscles are located under our skin and cover our skeleton.

Multiple Select

The muscular system is an organ that consists of.. (choose 3).

• Cardiac Muscles

• Skeletal Muscles

• Smooth Muscles

• Face Muscles

Types of Muscles

• Cardiac: makes up heart

• Skeletal: connects to bone, enables movement via contractions which pulls on the bone

• Smooth: forms organs that squeeze (stomach) , involuntary movement

Multiple Choice

The type of muscle shown below is...

• cardiac muscle

• smooth muscle

• skeletal muscle

Multiple Choice

The type of muscle shown below is...

• smooth

• skeletal

• cardiac

Multiple Choice

The type of muscle shown below is...

• skeletal

• smooth

• rough

• cardiac

Multiple Choice

The muscles we find in this organ are..

Multiple Choice

The muscles we find here are