Muscle and Movement

Question 1

What is muscle?

Answer 1

Muscle is a specialised tissue that is remarkably similar in all the animal kingdom.

Question 2

What are muscles made of?

Answer 2

Muscles are made up of proteins and consist of muscle fibres bound together by connective tissue.

Question 3

What are the 3 different types of muscle?

Answer 3

striated muscle, smooth muscle and cardiac muscle.

Question 4

What is striated muscle?

Answer 4

Striated muscle (skeletal or voluntary muscle) is the muscle attached to the skeleton and involved in locomotion. It is under the control of the voluntary nervous system, and its appearance under the microscope is striated or stripy. It contracts rapidly, but also fatigues or tires relatively quickly.

Question 5

What are muscle fibres made up of? What are those made up of?

Answer 5

They’re made up of many myofibrils lying parallel to each other. Each myofibril is made up of sarcomeres, the individual units of the muscle structure. The proteins actin and myosin make yo the large part of the structure sarcomeres.

Question 6

What are the two types of protein molecules that sarcomere is made up of?

Answer 6

Actin and Myosin

Question 7

How are contractions brought about?

Answer 7

By co-ordinated sliding of actin and myosin within the muscle cell sarcomeres.

Question 8

What two molecules are associated with actin?

Answer 8

Troponin and tropomyosin.

Question 9

What do myosin molecules look like?

Answer 9

Myosin molecules are shaped like golf clubs; the club shafts lie together as a bundle, with heads protruding along their length.

Question 10

Briefly, what is the sliding filament theory?

Answer 10

In a contraction, the change in orientation of the myosin heads brings about the movement of actin over the myosin.

Question 11

Where do muscles bring about movement?

Answer 11

At a joint. It is coordinated by several muscles.

Question 12

How do muscles move a joint?

Answer 12

Muscles contract, pulling on the bone and so moving the joint.Muscles can only pull, they cannot push, so at least two muscles are needed to move a bone to and.

Question 13

what are a pair of muscles that move a bone to and fro called?

Answer 13

Antagonistic.

Question 14

What are synovial joints?

Answer 14

The bones that articulate in the joint are seperated by a cavity filled with synovial fluid, which enables them to move freely.

Question 15

What are some examples of synovial joints?

Answer 15

Hips, knee and ankle joints.

Question 16

What is the structure of a synovial joint?

Answer 16

The bones are held in position by ligaments that control and restrict the amount of movement at the joint. Tendons attach muscles to the bones, enabling the muscles to power joint movement. Cartilage protects bones within joints.

Question 17

List the structures etc in a synovial joint.

Answer 17

Tendon, bone, muscle, ligament, synovial membrane, synovial fluid, cartilage, pad of cartilage, fibrous capsule.

Question 18

What is the function of a tendon?

Answer 18

It joins muscle to bone.

Question 19

What is the function of a ligament?

Answer 19

It joins bone to bone and is strong and flexible.

Question 20

What is the function of the synovial membrane?

Answer 20

It secretes synovial fluid.

Question 21

What is the function of synovial fluid?

Answer 21

It acts as a lubricant.

Question 22

What is the function of cartilage?

Answer 22

It absorbs synovial fluid and acts as a shock absorber.

Question 23

What is the function of a pad of cartilage?

Answer 23

It gives additional protection.

Question 24

What is the function of a fibrous capsule?

Answer 24

It encloses joints.