Anatomy & Physiology: Muscular System

Question 1

Muscular System

Answer 1

Responsible for all types of body movement and provides support, stabilizing joints, and generating heat for the body.

Question 2

Muscle Fibers

Answer 2

Specialized cells that make up all muscles.

Question 3

Cardiac Muscle

Answer 3

Consists of muscle cells that are striated, short, branched, and found in the walls of the heart.

Question 4

Skeletal Muscle

Answer 4

Cells are striated, long, and cylindrical. Attached to bones in the body.

Question 5

Smooth Muscle

Answer 5

Non-striated muscle cells that are spindle-shaped and found in the walls of internal organs like the bladder and stomach.

Question 6

Endomysium

Answer 6

Encases individual skeletal muscle fibers.

Question 7

Perimysium

Answer 7

Muscle fibers that are bundled together by a connective tissue.

Question 8

Fasciculi

Answer 8

Bundles of skeletal muscle fibers.

Question 9

Epimysium

Answer 9

Fascicles are bundled together by a strong connective tissue.

Question 10

Sarcolemma

Answer 10

The cell membrane that surrounds a skeletal muscle fiber.

Question 11

Sarcoplasm

Answer 11

The cytoplasm of the skeletal muscle fiber.

Question 12

Myofibrils

Answer 12

One muscle fiber is filled with several long, cylindrical proteins.

Question 13

Sarcomere

Answer 13

The smallest contractile unit in a myofibril.

Question 14

Myofilaments

Answer 14

A myofibril is the result of several of these. There are two types.

Question 15

Myosin

Answer 15

Thick bands, or myofilaments, are made of several protein molecules.

Question 16

Actin

Answer 16

Several protein molecules that link together to form the thin bands.

Question 17

Z-Disk or Z-Line

Answer 17

Thin actin bands are attached to this.

Question 18

I-Bands

Answer 18

Light-colored bands.

Question 19

A-Bands

Answer 19

Dark-colored bands,

Question 20

H-Zone

Answer 20

Found in the middle of the A-Bands.

Question 21

M-Line

Answer 21

Found in the middle of the H-Zone, center of the sarcomere.

Question 22

Slide Filament Theory

Answer 22

Actin filaments slide past myosin filaments, pulling the actin filaments closer to the center of the sarcomere, or M-Line. This sliding action happens because of interactions between the heads of actin and myosin. The heads of myosin form attachments with the actin myofilaments.

Question 23

Crossbridges

Answer 23

Attachments that are formed from the heads of myosin and the actin myofilaments.

Question 24

Sarcoplasmic Reticulum

Answer 24

Surrounds the myofibrils

Question 25

Ligament

Answer 25

Attach bones to bone.

Question 26

Joint

Answer 26

Where ligaments connect bones and the bones meet.

Question 27

Immovable Joint

Answer 27

These consist of bones held together by connective tissues. The bones are in very close contact. (Also known as Fibrous Joints)

Question 28

Partly Movable Joint

Answer 28

These consist of bones held together by cartilage. These joints allow some degree of movement. (Also known as Cartilaginous Joints)

Question 29

Synovial Joint

Answer 29

These allow the largest freedom of movement because the bones are separated by a joint cavity.

Question 30

Tendons

Answer 30

Attach muscle to bone.

Question 31

Flexor Muscle

Answer 31

The muscle that causes a joint to bend.

Question 32

Extension Muscle

Answer 32

The muscle that contracts and causes a joint to straighten.