The Muscles

Question 1

What are the functions of the muscular system

Answer 1

-movement of the body, maintenance of posture, respiration, production of body heat, communication, constriction of organs and vessels, contraction of the heart

Question 2

What are the general properties of the muscle?

Answer 2

-contractibility, excitability, extensibility, elasticity

Question 3

What are the 3 types of muscle tissue?

Answer 3

-cardiac,skeletal, smooth

Question 4

What is the function of skeletal muscle tissue?

Answer 4

-responsible for locomotion, facial expressions, posture, respiratory movements, other type of body movement
-voluntary
-appears striated (due to thick and thin filaments, cells are multinucleated

Question 5

What is the function of smooth muscle

Answer 5

-found in bladder, reproductive tracts, gastrointestinal tract, respiratory tract, surrounds blood vessels
-propel urine, mix food in digestive tract, dilating/constricting pupils, regulating blood flow
-in some locations autorhymic

Question 6

Smooth muscle is controlled involuntarily by the

Answer 6

-endocrine and autonomic nervous systems

Question 7

Visceral smooth muscle has numerous

Answer 7

-gap junctions (sheets of smooth muscle function as a unit); couple adjacent cells chemically and electrically, facilitating the spread of chemicals or action potentials between smooth muscle cells

Question 8

What are the function of caridiac muscle

Answer 8

-heart, major source of movement of blood, autorhythmic,controlled involuntarily by endocrine and autonomic nervous system

Question 9

What are skeletal muscles composed of and what is their appearance

Answer 9

-composed of muscle cells/fibers, connective tissue, blood vessels and nerves
-fibers are long, cylindrical and multinucleated
-striated appearance due to light and dark banding

Question 10

What is sarcolemma

Answer 10

-plamsa membrane of muscle fiber/cell

Question 11

What is sarcoplasm

Answer 11

-cytoplasm of muscle cell

Question 12

What is myofibril

Answer 12

-contractile elements found in muscle cells

Question 13

Contractibility

Answer 13

ability of a muscle to shorten with force

Question 14

Excitability

Answer 14

capacity of muscle to respond to a stimulus (from our nerves)

Question 15

Extensibility

Answer 15

Muscle can be stretched to its normal resting length and beyond to a limited degree

Question 16

Elasticity

Answer 16

Ability of muscle to recoil to original resting length after stretched

Question 17

Sarcomere

Answer 17

basic unit of contraction in a myofibiril, region between two z-lines

Question 18

muscle fiber=

Answer 18

muscle cell

Question 19

Z-disk

Answer 19

filamentous network of protein. Serves as attachments for actin filaments

Question 20

I bands

Answer 20

Between thick filaments

Question 21

A bands

Answer 21

Length of thick filaments

Question 22

H zone

Answer 22

region in A band where actin and myosin do not overlap

Question 23

Tropomyosin

Answer 23

An elongated protein that winds along the groove of the actin double helix

Question 24

Troponin

Answer 24

is found between the ends of the tropomyosin molecules in the groove between actin strands
-composed of three subunits, one that binds to actin, a second that binds to tropomyosin, and a third that binds to calcium ions

Question 25

The tropomyosin/troponin complex regulates

Answer 25

the interaction between active sites on actin and myosin

Question 26

Fast aerobic fibers

Answer 26

intermediate size, intermediate strength, some fatigue -contract relatively quickly and powerfully -fatigue more quickly than slow fibers -used in endurance activities

Question 27

Creatine phosphate

Answer 27

accumulates in muscle tissue, used up quickly -during resting condition stores energy to synthesize ATP kinase

Question 28

Anaerobic respiration

Answer 28

occurs in the absence of oxygen and results in breakdown of glucose to yield ATP and Lactic acid ex. short period of intense exercise(sprint): ATP from creatine phosphate and anaerobic respiration will last about 3 minutes

Question 29

Aerobic respiration

Answer 29

-more efficient than anaerobic -requires oxygen and breaks down glucose to produce ATP, CO2, and water

Question 30

Endurance training

Answer 30

can convert fast muscle fibers from anaerobic to aerobic Recall: fast anaerobic fatigue more rapidly than fast aerobic fibers

Question 31

Weight lifting

Answer 31

converts fast muscle fibers from aerobic to anaerobic Recall: fast anaerobic contract more rapidly and powerfully than fast aerobic fibers -fatigue more rapidly than fast aerobic fibers, but that's okay because lifting a weight doesn't take too long

Question 32

Isomeric

Answer 32

Muscle is at same length. Muscle can contract, but it only exerts force or tension, and doesn't shorten. An example would be holding an object up without moving it; the muscular force precisely matches the load, and no movement results

Question 33

Isotonic

Answer 33

Muscle length changes. Lifting an object at a constant speed is an example of an isotonic contraction. The tension in the muscle remains constant despite a change in muscle length

Question 34

What are the two types of isotonic contractions

Answer 34

concentric: causes muscles to shorten, thereby generating force eccentric: cause muscles to elongate in response to a greater opposing force