Soc 14- Muscular System

Question 1

Voluntary muscles

Answer 1

Voluntary muscles are under your control, you can choose
When to contract or relax them. All these muscles are attached
to the skeleton via tendons.
When your muscles contract
movement takes place.

Question 2

Involuntary muscles

Answer 2

Involuntary muscles are not under our control. They contract
and relax automatically controlled by the involuntary nervous
system. They can be found in the digestive organs, circulatory
and urinary systems.

The are usually made up of spindle shaped fibres. The
Involuntary muscles of the blood vessels are especially
important for sport. By the muscles contracting, and relaxing it
helps distribute blood to areas it is most needed.

Question 3

Cardiac muscles

Answer 3

Only found in the wall of the heart it is a very specialised type
of involuntary muscles. Cardiac muscle is made up of interlaced
fires. These fibres can spread electronical signals from the
brain right through the heart so that all the cells can contract
together This regulates your heart rate and means that when
you exercise your heart keeps pumping in the right way.

Question 4

The voluntary muscular system

Answer 4

The term ‘muscular system’ describes all the muscles in the body
and the way they work together. Working with the skeletal system,
muscles contract and relax to produce movement.

Muscles also define your body shape and help you to maintain your
posture whether sitting or standing.

The voluntary muscle system is of course crucial when exercising or
playing sport. You can train them to be stronger, work for longer
without tiring and be more flexible.

Question 5

Deltoid

Answer 5

Move arm in all directions at the shoulder

Question 6

Pectoralis major

Answer 6

Adduct the arm at the shoulder

Question 7

Latissimus dorsi

Answer 7

Adduct and extend the arm at the shoulder

Question 8

Biceps

Answer 8

Flex the arm at the elbow

Question 9

Triceps

Answer 9

Extend the arm at the elbow

Question 10

External obliques

Answer 10

Pull the chest downwards; flex and rotate the spinal column; one side contracting creates a side bend

Question 11

Gluteals

Answer 11

Adduct and extend the leg at the hips, pull the leg backwards

Question 12

Hip flexors

Answer 12

Flex the hip, help move the leg and knee up towards the body

Question 13

Quadriceps

Answer 13

Extend the leg at the knee

Question 14

Hamstrings

Answer 14

Flex the leg at the knee

Question 15

Gastrocnemius

Answer 15

Point the toes (plantar-flexes the ankle), help flex the knee

Question 16

Tibialis anterior

Answer 16

Pull the toes up towards the shin (dorsi-flexes the ankle)

Question 17

Muscle fibres

Answer 17

make up voluntary
(skeletal) muscle; divided into
type I, type lla and type llx.

Question 18

Type I

Answer 18

Slow twitch muscle fibres; suited to low intensity work, e.g. marathon running, as they can be used for a long period without fatiguing.

Question 19

Type II

Answer 19

Fast twitch muscle fibres used in anaerobic work; can be improved through endurance training to increase their resistance to fatigue.

Question 20

Type IIx (explosive)

Answer 20

Fast twitch muscle fibres used in anaerobic work and can generate much greater force than other fibre types, but fatigue quickly.

Question 21

Myoglobin

Answer 21

A red pigment that transports oxygen to the muscles

Question 22

Antagonistic pair

Answer 22

Muscles that work together to create movement.