Support And Movement In Animals

Question 1

What is a hydrostatic skeleton

Answer 1

Skeleton that consists of water filled cavities surrounded by muscle

Question 2

How does a hydrostatic skeleton work

Answer 2

Fluid exerts pressure that provides support and allows animal to change shape for movement

Question 3

What are examples of animals with a hydrostatic skeleton

Answer 3

Earthworms
Sea anemones
Jellyfish

Question 4

What are disadvantages of hydrostatic skeletons

Answer 4

Allow slow movement
Limit size of animal
No protection

Question 5

What is an exoskeleton and in which animals does it occur

Answer 5

Skeleton made from chitin that occurs outside of the animals body
Occurs in arthropods

Question 6

What are the advantages of exoskeletons

Answer 6

Protect underlying tissue
Protect from desiccation
Allows for movement
Allows for attachment of muscle = quick movement
Can form wings in some insects which enable flight

Question 7

What are the disadvantages of exoskeletons

Answer 7

Weight is exoskeleton limits size of animal
Skeleton is impermeable to gas = need special respiratory system
Exoskeleton cannot grow = animals moult and shed old skeleton to get new skeleton = no proper protection so vulnerable to predators

Question 8

What are the advantages of an endoskeleton

Answer 8

Living tissue = grows with organism
Provides structural support and shape to body
Place of attachment of muscles
Protects internal organs

Question 9

What are the disadvantages of an endoskeleton

Answer 9

Does not offer protection against desiccation

Question 10

What are the functions of the human skeleton

Answer 10

Movement - anchor for muscles
Protection - e.g ribs protect lungs and heart and skull protects brain
Support - provides structural support and gives shape
Mineral storage - calcium and phosphates stored in bone
Blood cell formation - red and white blood cells formed in red bone marrow
Hearing - 3 ear ossicles transmit and amplify sound to enable hearing

Question 11

What do the appendicular and axial skeleton consist of

Answer 11

Appendicular:
Limbs
Pelvic girdle
Pectoral girdle

Axial:
Skull
Spine
Rib cage

Question 12

What does the skull consist of

Answer 12

Flat bones fused by sutures
Opening through which spinal cord enters skull = foramen magnum

Question 13

What are frontanelles and why are they important

Answer 13

Filled spaces that exist between cranium bones
Important to aid in neutral birth and allow for growth of baby’s brain before sutures start growing

Question 14

What is the function of the vertebral column

Answer 14

Supports skull
Surrounds and protects spinal cord
Place of attachment of ribs and pelvic and pectoral girdle
S shape curvature provides flexibility and absorb shock

Question 15

What is the structure of the vertebral column

Answer 15

Comprised of 33 bones
Bones joined by cartilage discs which allow some flexibility
Cervical vertebrae = 7; atlas is the first and allows for nodding, axis is the second and allows to move side to side
Thoracic vertebrae = 12; place of attachment of ribs
Lumbar vertebrae = 5; form lower back
Sacrum = 5 fused vertebrae that are place of attachment for pelvic girdle
Coccyx = 4 fused vertebrae, our tail bone

Question 16

What does the ribcage consist of

Answer 16

12 pairs of ribs
7 pairs true ribs - directly connect to the sternum
3 pairs false ribs - connect indirectly to sternum (connects to cartilage of rib above)
2 pairs floating ribs - connect to thoracic vertebrae only

Question 17

What are the functions of the ribcage

Answer 17

Protects heart and lungs
Plays a role in breathing - movement of ribcage changes thoracic pressure during breathing

Question 18

Which bones make up the pectoral girdle and what is its functions

Answer 18

Clavicle and scapula
Attaches upper limbs to the axial skeleton
Allows for movement of upper limbs

Question 19

What are the three types of joints and what is an example of each

Answer 19

Immovable joints / fibrous joint - sutures between cranium bones
Semi-moveable / cartilaginous joint - joints between vertebrae and pubic symphysis
Synovial joints - (allow free movement) shoulder and elbow joints

Question 20

What are the different types of synovial joints, how much movement does each allow and what are examples of each

Answer 20

Ball and socket - movement in any direction, e.g: shoulder and hip
Hinge - movement in one plane, e.g: elbow and knee
Gliding/plane joint - limited movement in any direction, e.g: wrist and ankle
Pivot - allow head to turn side to side e.g: atlas on axis and joint between radius and ulna

Question 21

What causes a joint injury

Answer 21

Torn/stretched ligament and tendon
Sprain or strain
Dislocation

Question 22

How do antagonistic pairs work

Answer 22

Muscle pairs with opposite functions, as one contracts another relaxes
Contract = flex; extend = relax

Question 23

What is rickets

Answer 23

Deficiency disease where bones weaken and bend as they grow caused by lack of vitamin D or calcium

Question 24

What is osteoporosis

Answer 24

Disease of the bones that causes loss in bone density
Caused by shortage of calcium
Bones weaken and fracture easily
Most common in older women

Question 25

What is arthritis

Answer 25

Condition that causes severe pain and loss of movement and joints
Two types of arthritis: osteoarthritis and rheumatoid arthritis
Osteoarthritis = cartilage lining joint disintegrates with age and bones grind against each other causing pain and inflammation
Rheumatoid = synovial membrane produces to much synovial fluid which causes inflammation; autoimmune disease where body attacks it’s own tissues

Question 26

What is muscular dystrophy

Answer 26

Genetic disease that causes deterioration of skeletal muscles
No cure
Sufferers slowly lose use to their limbs

Question 27

How does gout affect the joints

Answer 27

Urea acid crystals build up in the joints causing redness and swelling in toes