Chp 11-Functional Characteristics of Muscle

Question 1

Excitability

Answer 1

(responsiveness) – muscles can be stimulated by electrical, chemical, and physical means.

Question 2

Contractility

Answer 2

muscle responds to stimuli by contracting.

Question 3

Elasticity

Answer 3

muscles tend to recoil to their resting length.

Question 4

Extensibility

Answer 4

muscles can be stretched beyond their resting length.

Question 5

3 muscle types?

Answer 5

1. skeletal muscle
2. smooth muscle
3. cardiac muscle

Question 6

skeletal muscle

Answer 6

1. Location: attached to bones for movement
2. Characteristics: long, cylindrical, cells: multinucleated, striated
3. Control: voluntary

Question 7

smooth muscle

Answer 7

1. location: single unit: GI, respiratory, & genitourinary tract mucous membranes. Multi-unit arteries, arrector pili, airways
2. Characteristics: small oblong or spindle-shaped cells, 1 nucleus in center. Has both longitudinal & circular layers which facilitate peristalsis, NOT STRIATED
3. Control: Involuntary

Question 8

cardiac

Answer 8

1. Location: muscle of the heart
2. Characteristics: short, branching cells, mononucleated, faintly striated
3. Control: Involuntary

Question 9

Smooth Muscle Arrangement - intestine: 2 distinct layers

Answer 9

1. longitudinal (run along length_ - peristalsis
2. circular (wraps around) - segmentation

Question 10

The circular layer runs around the intestine and its contraction causes?

Answer 10

segmentation

Question 11

The longitudinal layer runs along the intestine; it causes?

Answer 11

peristalsis or wave-like contractions

Question 12

Types of Smooth Muscle Fibers?

Answer 12

1. single unit
2. Multi-unit

Question 13

single unit

Answer 13

smooth muscle - cells connected to function as a single unit (syncthium)
–visceral muscle
–e.g. in GI tract, produces peristalsis