(Part 3) Class 7 - Muscle Tissue (Neuro and Chemical)

Question 1

What is ATP and what does it do?

Answer 1

ATP (Adrenosphene Triphosphate) is the body’s most important energy transfer molecule. It is key in muscle contraction.

Question 2

The neurochemical _____ also known as ____ functions as a chemical messenger in the excitation phase of muscle action.

Answer 2

ACh, (ascetylcholine)

Question 3

A myofibril in a muscle is a bundle of ____________.

Answer 3

Myofilaments

Question 4

There are 3 kinds of myofilaments, elastic filaments, ________ and ___________.

Answer 4

Thick Filaments (Myosin) and Thin filaments (Actin).

Question 5

Myosin and actin are called _____ ______ because they _____ the muscle fibers.

Answer 5

contractile protiens, shorten

Question 6

________ is the calcium _______ protein in muscle contraction.

Answer 6

Actin, binding

Question 7

________ ________ are made of several hundred _____ molecules that have golf club shaped heads in the bundle.

Answer 7

Thick myofilaments, Myosin

Question 8

_____ ______ are made of two intertwining strands of ______ with calcium binding molecules attached.

Answer 8

Thin myofilaments, Actin

Question 9

The contractile proteins ____ and _______ interact with the ______ proteins (tropomyosin and troponin) to contract a muscle fiber which is activated by the release of ______ into the ______ and its binding to troponin.

Answer 9

Actin, Myosin, regulatory, Calcium, sarcoplasm

Question 10

In sliding filament theory a _________ or the segment of myofibril between one _______ and the next shortens and pulls pull the ______ closer together due to contractile proteins myosin and actin’s actions.

Answer 10

Sarcomere, z-disk, z-disks,

Question 11

A ______ _______ consists of one nerve fiber and the ______ _______ it innervates.

Answer 11

motor unit, muscle fibers

Question 12

True or False: Actin and Myosin shorten during contraction.

Answer 12

False. They cause the individual sarcomeres to shorten and z disks to come closer together.

Question 13

Skeletal muscle never contracts unless _____ by a _________.

Answer 13

stimulated , nerve

Question 14

When muscle fibers contract in a motor unit, they contract ______ ______.

Answer 14

in unison.

Question 15

A _______ is a gap where chemical transfer occurs and a nerve fiber meets its _____ ____ in the neuromuscular junction.

Answer 15

synapse, target cell

Question 16

_______ cells envelope a neuromuscular junction and isolate them from surrounding tissue fluid.

Answer 16

Schwann

Question 17

Three ways a signal stops in the neuromuscular cycle are ________, ________ and ________.

Answer 17

diffusion, reuptake and degradation ( with AChe)

Question 18

In the excitation phase _______ stimulates the release of _______ to prepare the muscle fiber for the next phase toward contraction.

Answer 18

ACh (ascetalcholine),calcium

Question 19

In contraction the ___ head must have an ____ molecule bound to it to initiate the process.

Answer 19

myosin, ATP

Question 20

_______ ________ is a disease caused by lack of ACh receptors.

Answer 20

Myasthenia gravis.

Question 21

A strain is a tear in __ or _____. A sprain is a tear in _________.

Answer 21

Muscle, tendon, ligament.

Question 22

Cardiac muscle is ____ like skeletal muscle and it is repaired by __.

Answer 22

striated, fibrosis