Muscular System - The body

Question 1

Skeletal muscle

Answer 1

Forms the majority of the muscle tissue in the body
Consists of parallel bundles of long, multinucleated fibres with transverse stripes.
Capable of powerful contractions, and is innervated by somatic and branchial motor nerves.
Used to move bones and other structures
Provides support and gives form to the body.
Named on the basis of shape (e.g., rhomboid major muscle), attachments (e.g., sternohyoid muscle), function (e.g., flexor pollicis longus muscle), position (e.g., palmar interosseous muscle), or fiber orientation (e.g., external oblique muscle).

Question 2

Cardiac muscle

Answer 2

Striated muscle is found only in the walls of the heart (myocardium) and some large vessels close to where they join the heart.
Consists of a branching network of individual cells linked electrically and mechanically to work as a unit.
Contractions are less powerful than the skeletal muscles and are resistant to fatigue.
Innervated by visceral motor nerves.

Question 3

Smooth muscle

Answer 3

Absence of stripes
Consists of elongated or spindle shaped fibres capable of slow and sustained contractions.
Cound in the walls of blood vessels (tunica media)
Associated with hair follicles in the skin, located in the eyeball, and found in the walls of various structures associated with gastrointestinal, respiratory, genitourinary, and urogenital systems.
Innervated by visceral motor nerves.

Question 4

Cardiac muscle histology

Answer 4

Rectangular shape
Single nucleus
Multiple mitochondria

Question 5

skeletal muscle histology

Answer 5

Cylindrical
Striated
Multinucleated
Multiple mitochondria

Question 6

smooth muscle histology

Answer 6

Spindle shaped
Single central nucleus
Arranged in sheets

Question 7

How do muscle and fascia relate

Answer 7

Individual muscles are surrounded by Investing Fascia.

Question 8

Muscle atrophy

Answer 8

Wasting disorder of muscles
Produced by a variety of causes including nerve damage to the muscle and disuse
Often seen in patients with paralysis.

Question 9

Muscle paralysis

Answer 9

Can be associated with neurological problems
Can lead to muscle atrophy in long term
Major causes: stroke, trauma, amd poliomyelitis

Question 10

Circular muscle

Answer 10

mouth, eyes

Question 11

Convergent muscle

Answer 11

Pectoralis major

Question 12

Parallel muscle

Answer 12

(strap muscles) sartorius

Question 13

Pennate muscles

Answer 13

Unipennate: diagonal direction; Lumbricals
Bipennate: two rows of muscle fibres in opposite diagonal directions; Rectus Femoris
Multipennate: multiple rows of diagonal fibres; deltoid

Question 14

Fusiform muscles

Answer 14

Biceps Brachii