Muscular System - Module 3

Question 1

What are the functions of the muscular system?

(How many muscles are there?)

Answer 1

• Helps with body movement
• Supports body posture
• Produces heat and energy
• Protects internal organs
• Helps transport blood, food, waste throughout the body
• Opens/closes body openings

(There are 639 muscles in the body)

Question 2

What are the 4 muscle traits? What is muscle tone?

Answer 2

• Excitability/Irritability - ability to respond to stimuli
• Contractability - ability to shorten/produce movement when stimulated
• Extensibility - ability to be stretched/lengthened
• Elasticity - ability to return to original shape after contraction
• Muscle tone - ability of muscle to be slightly contracted at all times

Question 3

What is the microscopic make-up of different types of muscles?

Answer 3

• Skeletal - Striated with alternating dark/light bands
• Visceral - Narrow, not striated, single, central nucleus
• Cardiac - Striated with alternating dark/light bands

Question 4

What are the types of bodily movements?

flexion, extension, abduction, adduction, rotation

Answer 4

• Flexion - decreasing joint angle
• Extension - increasing joint angle
• Abduction - moving a limb away from the midline
• Adduction - moving a limb towards the midline
• Rotation - turning a body part around on its axis to produce circular/semi-circular motion

Question 5

What are the types of bodily movements (extended)

circumduction, supination, pronation, dorsiflexion, plantar flexion

Answer 5

• Circumduction - movement of body region in a circular manner
• Supination - movement of the forearm where the palm faces anteriorly
• Pronation - movement of the forearm where the palm faces posteriorly
• Dorsiflexion - movement(s) at the ankle where the foot faces up (standing on heels)
• Plantar flexion - movement(s) at the ankle where the foot faces down (standing on toes)

Question 6

What are the types of bodily movements (extended II)

inversion, eversion, protraction, retraction

Answer 6

• Inversion - turning of the foot towards the midline
• Eversion - turning of the foot away from the midline
• Protraction - moving the scapula forward
• Retraction - moving the scapula backwards, towards the vertebral column

Question 7

What long-term injury occurs when muscles jerk suddenly and become injured, preventing full extension after?

Answer 7

Muscle strain (pulling/tearing of fibers or tendon(s))

Question 8

Which muscle disorders produce chronic pain in specific muscle sites?

Answer 8

Fibromyalgia