Muscular skeletal system (21)

Question 1

What is the essential function of muscle?

Answer 1

> Contraction (shortening)- a unique characteristic that sets it apart from any other body tissue
Due to this, muscles are responsible for essentially all body movement

Question 2

What does the muscular skeletal system consist of?

Answer 2

> Accounts for 75% of body weight
206 bones
Others including muscles, joints, ligaments, tendons, fascia, bursae, cartilage and synovial lining

Question 3

What are the 3 types of muscle tissue?

Answer 3

> Skeletal, cardiac and smooth

> Differ in their cell structure, body location and how they are stimulated to contract

Question 4

What are the similarities of the different muscle types?

Answer 4

1) Skeletal and smooth muscle cells are elongated and therefore called muscle fibres
2) The ability of muscle to contract (shorten) depends on 2 types of myofilaments
3) Myo- and Mys- always refers to muscle

Question 5

What are the characteristics of skeletal muscle?

Answer 5

> Location- attached to bones or skin

> Appearance- Single, very long, cylindrical, multinucleate cells with obvious striations (groove over the surface)

Question 6

What are the characteristics of cardiac muscle?

Answer 6

> Location- walls of heart

> Appearance- Branching chains of cells; uni or binucleate; striations

Question 7

What are the characteristics of smooth muscle?

Answer 7

> Location- Single-unit muscle in walls of hollow visceral organs (other than the heart); multiunit muscle in intrinsic eye muscles; airways; large arteries
Appearance- Single, fusiform (wide in the middle and narrow at the ends), uninucleate, no striations

Question 8

What is skeletal muscle?

Answer 8

> Skeletal muscle fibres are packaged into the organs called skeletal muscles that attach to the skeleton
As they are attached to bony underpinnings, they form the smooth contours of the body and are huge, cigar-shaped, multi-nucleate cells
Largest type of muscle fibre, up to 1 foot in length- fibres of large hardworking muscles, such as antigravity muscles of the hip (e.g. gluteus maximus)

Question 9

Skeletal muscles- striated and voluntary

Answer 9

> Striated- fibres have obvious stripes
Voluntary- The only muscle type subject to conscious control
Often activated with reflexes
Can contract rapidly and with great force but tires easily and must rest after short periods of activity
Soft and fragile
Can exert tremendous amounts of power