The Muscular System

Question 1

How many muscles are there in the body?

Answer 1

650

Question 2

What are the four characteristics of the muscles?

Answer 2

Excitability, contractility, extensibility and elasticity

Question 3

What are the four roles of the muscles?

Answer 3

Produce movement, stabilise the body, store substance and generate heat

Question 4

What is the fasical net?

Answer 4

The area where muscles are attached to bones and usually cross one or more joints

Question 5

What is a cardiac muscle?

Answer 5

Involuntary muscle which forms the walls of the heart. Purpose is to pump blood around the Circulatory system

Question 6

What is a skeletal muscle?

Answer 6

Its is attached to bone, and is a voluntray muscle tissue as it is consciousily controlled.

Question 7

What is a smooth muscle?

Answer 7

Involuntary muscle that assists with the movement of blood and food through the relevant systems of the body. It contracts without us even knowing about it

Question 8

What is a tendon?

Answer 8

Connective tissue that connects muscle to bone and is capable of withstanding tension. Elastic properties allow them to operate and store and release energy.

Question 9

What is an agonist?

Answer 9

Prime mover - the muscle which contracts the most to bring about the desired movement

Question 10

What is an antagonist?

Answer 10

The muscle which is on the opposite side of the body that allows for movement of the agonist by downgrading the amount of activity it provides.

Question 11

What is a synergist?

Answer 11

Assists with the movement. They help the agonist to perform the desired movement

Question 12

What is a fixator?

Answer 12

Contracts to make the moving joint stable. These muscles help to keep the other parts of the body stationary

Question 13

What is the muscle belly?

Answer 13

The main body of the muscle

Question 14

What is the epimysium?

Answer 14

The entire muscle is enclosed in an outer sheath of fibrous connective tissue

Question 15

What is the fasciculi?

Answer 15

A bundle of fibres, usually muscle or nerve fibres

Question 16

What is the perimysium?

Answer 16

A membrane that protects and supports groups of fibres within the skeletal muscle

Question 17

What is the Levator ani?

Answer 17

Supports pelvic viscera and provides spincter-like action in the anal canal and vagina

Question 18

What is the superficial transverses perinea?

Answer 18

Supports pelvic viscera

Question 19

What is the bulbospongiosus?

Answer 19

For males it assists in emptying urethra. For females it contracts the vagina

Question 20

What is the ischiocavernosus?

Answer 20

Assists with the function of bulbospongiosus

Question 21

What is the sliding filament theory?

Answer 21

States how muscles contract. During muscle contraction, the cross bridges on the myosin filaments, attach to the actin filaments and pull the actin towards the centre of the sarcomere. As the actin moves, the cross bridge detach and reattach further along the actin to continue the process. This is called cross bridge cycling. During the contraction, the actual length of each actin and myosin filament does not change.

Question 22

What is a slow twitch fibre Type I?

Answer 22

contain large amounts of myoglobin, many mitochondria and many blood capillaries. Type I fibres are red, split ATP at a slow rate, have a slow contraction velocity, very resistant to fatigue and have a high capacity to generate ATP by oxidative metabolic processes. Such fibres are found in large numbers in the postural muscles of the neck.

Question 23

What is a Fast Twitch Fibres (Type II A or Fast Glycolytic Fibres)?

Answer 23

contain very large amounts of myoglobin, very many mitochondria and very many blood capillaries. Type II A fibres are red, have a very high capacity for generating ATP by oxidative metabolic processes, split ATP at a very rapid rate, have a fast contraction velocity and are resistant to fatigue. Such fibres are infrequently found in humans.

Question 24

What is a Fast Twitch Fibres (Type II B or Fast Glycolytic Fibres)?

Answer 24

contain a low content of myoglobin, relatively few mitochondria, relatively few blood capillaries and large amounts glycogen. Type II B fibres are white, geared to generate ATP by anaerobic metabolic processes, not able to supply skeletal muscle fibres continuously with sufficient ATP, fatigue easily, split ATP at a fast rate and have a fast contraction velocity. Such fibres are found in large numbers in the muscles of the arms.