Topic 7: Support system in animal

Question 1

What are the 3 types of skeleton?

Answer 1

Hydrostatic skeleton
Exoskeleton
Endoskeleton

Question 2

Esplain the hydrosketelon.

Answer 2

Soft-bodied invertebrates are supported by the fluid inside their bodies
Fluid fills the body cells and cavities
Muscles contract against the fluid
Fluid provides excellent support but not shape

Question 3

What are the advantages and disadvantages of the hydrostatic skeletons?

Answer 3

Advantages:
-Does not require specialised
support structures or tissues

Disadvantages:
-No protection
-Limited size
-Limited speed

Question 4

Explain the exoskeleton.

Answer 4

Hard outside
Found in arthropods and crustaceans
Made up of chitin
Chitin forms body plates with flexible joints
Muscles attach to it

Question 5

What are the advantages and disadvantages of the exoskeleton?

Answer 5

Advantages:
-Provides body support and attachment for
muscles.
-Reduces water loss.
-Thin and flexible at joints for movement.
-Protects from injury

Disadvantages:
-Chitin cannot grow or stretch – animal must moult.
-During moulting – body
unprotected, easy prey.
-Limited size

Question 6

Explain the endoskeleton.

Answer 6

Skeletons inside the body
Lower chordates:
-notochord
-single supporting rod, below central nerve cord
-acts as internal skeleton
-muscles act against it
Vertebrates:
-notochord replaced by vertebral column
-made of cartilage or bone
-Surrounds and protects central nerve cord

Question 7

What are the advantages and disadvantages of the endoskeleton?

Answer 7

Advantages:
-Joints make body flexible
-Animals can grow larger as skeleton tissue grows
-Protects internal organs from injury
-Provide structural support
-Provide more positions for attachment of muscles

Disadvantages:
-Takes long to repair damage

Question 8

What is the function of the skeleton?

Answer 8

1. Forms framework to support other parts of
   body
2. Protects vital organs
3. Allows muscle movement
4. Aid in hearing
5. Store calcium and phosphorus for hardness
6. Long bones manufacture blood cells

Question 9

What is the difference between tendons and ligaments?

Answer 9

Tendons:
-Attach muscle to bone
-Elastin fibres: cannot stretch
-Made of fibrous tissue

Ligaments:
-Holds bone together
-Collagen fibres: provide strength
Elastin fibres: can stretch
-Made of fibrous tissue

Question 10

What is a fracture?

Answer 10

A break in a bone

Question 11

What is an X-ray?

Answer 11

Pass through soft tissue, but not bone - shows whether or not bone has been broken

Question 12

What is a herniated disc?

Answer 12

A herniated disc is a fragment of the disc nucleus that is pushed out of the annulus, into the spinal canal through a tear or rupture in the annulus.

Question 13

What are the 3 types of joints?

Answer 13

Fibrous
Cartilaginous
Synovial

Question 14

Explain the difference between fibrous, cartilaginous and synovial joint.

Answer 14

Fibrous:
-Immovable
-Joints between bones of skull

Cartilaginous:
-Slightly movable
-Between vertebrae

Synovial:
-Moveable
-Knee or elbow joints

Question 15

What are the 4 types off synovial joints and the direction they allow movement?

Answer 15

Ball-and-socket:
-All directions
-Shoulder

Hinge:
-One direction
-Elbow

Pivot:
-One bone pivots on another
-Between atlas and axis

Gliding:
-Flat surface of one bone glides across surface of bone next
-Ankle

Question 16

What is the role of bone in movement?

Answer 16

Skeletal bones need muscles for movement, need attachments for both ends to produce movement.
Skeleton provides these points of attachment.
They play important role in support of skeleton
Bones act as levers

Question 17

What is the role of muscle in movement?

Answer 17

Skeletal muscles allow movement to take place
Tendons attach muscles to bone – muscle contracts – pulls on bone
Muscles always work in antagonistic pairs to bring about movement: when one muscle contracts, the other muscle relaxes

Question 18

What is the role of joints in movement?

Answer 18

Where 2 or more bones come together.
Allow body to perform range of movement in different directions.
Prevent friction between ends of bones during movement.

Question 19

What is the role of tendons in movement?

Answer 19

Attach muscles to bone and pull on bones.
Function – to ensure that the force produced by the contraction of muscles is transmitted to part of body to be moved.

Question 20

What is the rold of ligaments in movement?

Answer 20

Hold bones together at joint.
Ligaments control direction and extent to which joint can move.
Prevent dislocation of joints by holding joint capsule in place.

Question 21

What is a dislocation?

Answer 21

When bones slip out of their proper alignment in joint

Question 22

What is the difference between sarcolemme, sarcoplasm and sarcomeres?

Answer 22

Sarcolemma: membrane around muscle fibre.
Sarcoplasm: cytoplasm of muscle fibres.
Sarcomeres: Units of each fibres in skeletal muscle

Question 23

Explain muscle contraction.

Answer 23

Each muscle fibre made up of smaller units –
myofibrils.
Myofibrils made of two types of protein - actin &
myosin.
Myosin filaments are slightly thicker than
actin filaments
When skeletal muscle contracts actin filaments slide inwards between myosin filaments causing sarcomeres to become shorter.
Each muscle fibre is made up of many sarcomeres, when they all shorten together the whole muscle fibre contracts

Question 24

What is arthritis?

Answer 24

Condition that affects the joints.
Cartilage and synovial fluid sacs break down providing less protection and cushioning – bones rub on one another – cause pain and inflammation.
Bones also form spurs – even more pain and instability

Question 25

What is the causes and treatment of arthritis?

Answer 25

Causes:
-Obesity – puts pressure on joints
-Heredity and genetics also play role.
-Sports injuries.

Treatment:
-Aspirin and cortisone – reduces pain and
inflammation
-Exercise – helps by strengthening the
muscles around joint
-Traditional medication