Chapter 11: Muscular Tissue

Question 1

What are the 5 universal characteristics of muscle? ECCEE

Answer 1

Excitability (responsiveness)
Conductivity
Contractility
Extensibility
Elasticity

Question 2

A voluntary striated muscle that is usually attached to one or more bones. Cells of this muscle exhibit alternating light and dark transverse bands or striations.

Answer 2

Skeletal muscle

Question 3

This component of muscle is neither excitable nor contractile but it is somewhat extensible and elastic. When a muscle lengthens, it keeps it from excessive stretching and protects it from injury.

Answer 3

Collagen

Question 4

A bundle of muscle fibers

Answer 4

Fascicle

Question 5

The sarcoplasm of muscle fibers contains what 3 things? MGM

Answer 5

Myofibrils
Glycogen
Myoglobin

Question 6

These are long protein cords contained inside muscle fiber.

Answer 6

Myofibrils

Question 7

This is a starch-like carbohydrate that provides energy for the cell during heightened levels of exercise.

Answer 7

Glycogen

Question 8

Red-oxygen binding pigment that provides some of the oxygen needed for muscular activity.

Answer 8

Myoglobin

Question 9

The sarcoplasmic reticulum of muscle fibers is contained where?

Answer 9

Wrapped around each myofibril like a mesh stocking around one’s leg.

Question 10

Where is calcium stored in muscle fibers?

Answer 10

Sarcoplasmic reticulum

Question 11

The sarcoplasmic reticulum has dilated end sacs that are called ____________ which cross the muscle fiber from one side to the other.

Answer 11

Terminal cisterns

Question 12

Adult stem cells that play in important role in muscle growth and in the repair of fiber injuries on a larger scale.

Answer 12

Satellite cells

Question 13

Each myofibril is a bundle of filaments called _______.

Answer 13

myofilaments (muscle filaments)

Question 14

What are the 3 kinds of myofilaments?

Answer 14

Thick filaments
Thin filaments
Elastic filaments

Question 15

Thick myofilaments consists of a bundle of 200-500 molecules of a motor protein called _______.

Answer 15

Myosin

Question 16

Thin myofilaments are composed of two intertwined strands called __________ which are made of subunits called __________. Also thin filaments contains 40- 60 molecules of a protein called ____________.

Answer 16

Fibrous (F) actin; globular (G) actin; tropomyosin

Question 17

In thin filaments, tropomyosin contains a two-part calcium-binding protein called _________ that binds to it.

Answer 17

Troponin

Question 18

Elastic filaments are made up of a huge springy protein called _________ that run through the core of each thick filament and anchor it to structures.

Answer 18

Titin

Question 19

Myosin and actin are called _________ proteins because they do the work of shortening the muscle fiber.

Answer 19

Contractile

Question 20

Tropomyosin and troponin are called _________ proteins because together they act as a switch to determine when the fiber can contract and when it can’t.

Answer 20

Regulatory

Question 21

What is released into the sarcoplasm of muscle fibers to activate contraction?

Answer 21

Calcium ions

Question 22

Calcium binds to&raquo_space;»»

Answer 22

troponin

Question 23

Which protein blocks the active sites of actin so that myosin cannot bind to it when the muscle isn’t stimulated

Answer 23

Tropomyosin blocks active sites of globular actin

Question 24

An enormous protein located between sarcolemma and outermost myofilaments. It links actin filaments to a peripheral protein on the inner face of sarcolemma. Genetics defects of this protein is responsible for disabling disease muscular dystrophy.

Answer 24

Dystrophin

Question 25

Segment of myofibril that allows for muscle to contract and relax.

Answer 25

Sarcomere

Question 26

Skeletal muscles are served by nerve cells called ___________.

Answer 26

Somatic motor neurons

Question 27

Axons of somatic motor neurons that lead to the muscles and whose cell bodies are in the brainstem and spinal cord.

Answer 27

Somatic motor fibers

Question 28

One nerve fiber and all the muscle fibers innervated by it are called a ________.

Answer 28

Motor unit

Question 29

Point of communication where a nerve fiber meets any target cell is called a __________.

Answer 29

Synapse

Question 30

Synapse where a nerve fiber meets a muscle fiber

Answer 30

neuromuscular junction or motor end plate