Key Terms Chapter 10

Question 1

The scientific study of muscles is ______

Answer 1

Myology

Question 2

Three types of muscular tissue include:

Answer 2

Skeletal muscle tissue, cardiac muscle tissue, and smooth muscle tissue

Question 3

Built-in rhythm that initiates contractions involuntarily

Answer 3

Autorhythmicity

Question 4

AS muscular tissue contracts, it produces heat, a process known as ________.

Answer 4

Thermogenesis

Question 5

Four key functions of muscular tissue:

Answer 5

Producing body movements, stabilizing body positions, storing and moving substances within the body, and generating heat.

Question 6

Four special properties of muscular tissue:

Answer 6

Electrical excitability, contractility, extensibility, and elasticity.

Question 7

Another name of a muscle cell is _____

Answer 7

Muscle fiber due to their elongated shape

Question 8

The _______ separates muscle from skin and is composed of areolar connective tissue and adipose tissue.

Answer 8

Subcutaneous layer or hypodermic

Question 9

A dense sheet or broad band of irregular connective tissue that lines the body wall and limbs and supports and surrounds muscles and other organs of the body

Answer 9

Fascia

Question 10

The outer layer of dense irregular connective tissue that encircles the entire muscle

Answer 10

Epimysium

Question 11

A layer of dense irregular connective tissue that surrounds a group of 10 or more muscle fibers separating them into fascicles.

Answer 11

Perimysium

Question 12

Made up of mostly reticular fibers, this penetrates the interior of each fascicle and separates individual muscle fibers from one another.

Answer 12

Endomysium

Question 13

The plasma membrane of a muscle cell

Answer 13

Sarcolemma

Question 14

The cytoplasm of a muscle fiber

Answer 14

sarcoplasm

Question 15

This protein, found only in muscle, binds oxygen molecules that diffuse into muscle fibers from interstitial fluid and releases it when needed by the mitochondria for ATP production.

Answer 15

Myoglobin

Question 16

Tiny, striated threadlike structures found in the sarcoplasm of muscle fibers. The contractile organelles of skeletal muscle.

Answer 16

Myofibrils

Question 17

A fluid-filled system of membraneous sacs that encircles each myofibril.

Answer 17

Sarcoplasmic Reticulum (SR)

Question 18

The replacement of muscle fibers by fibrous scar tissue.

Answer 18

Fibrosis

Question 19

Tiny invaginations of the sarcolemma of each muscle fiber that are filled with interstitial fluid.

Answer 19

Transverse tubules

Question 20

Dilated end sacs of the SR that butt against the T tubule from both sides.

Answer 20

Terminal cisterns

Question 21

A transverse tubule and the two terminal cisterns form a _____.

Answer 21

Triad

Question 22

Smaller protein structures within myofibrils are ______.

Answer 22

Myofilaments

Question 23

The two types of myofilaments or contractile proteins are ______ and ______.

Answer 23

Actin (thin filament) and Myosin (thick filament)

Question 24

Basic functional unit of myofibrils.

Answer 24

Sarcomeres

Question 25

These plate-shaped regions of dense protein material separate one sarcomere from the next

Answer 25

Z discs

Question 26

A sarcomere extends from ____ to ____.

Answer 26

Z disc to Z disc

Question 27

The darker middle part of the sarcomere which extends the entire length of the thick filaments is the ____.

Answer 27

A band

Question 28

The lighter, less dense area that contains the rest of the thin filaments and no thick filaments is the ______. *A Z disc passes through the center of each I band*

Answer 28

I band

Question 29

A narrow _______ in the center of each A band contains thick but no thin filaments

Answer 29

H zone

Question 30

Supporting proteins that hold the thick filaments together at the H zone form the ____.

Answer 30

M line (m for middle of the sarcomere)

Question 31

Site covered by tropomyosin where myosin head can attach to actin

Answer 31

Myosin binding site

Question 32

Two regulatory proteins of thin filaments:

Answer 32

Tropomyosin and troponin

Question 33

Tropomyosin proteins that cover the myosin binding sites on actin (in relaxed muscles) are held in place by _______ molecules.

Answer 33

Troponin