Biology Textbook P.170

Q.3

i ) A – contract     B – relax

ii ) X – ball and socket joint   Y – hinge joint

iii ) cartilage / fluid

iv ) B, C, ( A )

-         backbone will bend / damage

-         muscle become fatigue and he feels pain

-         breathing movement restricted

-         digestive system congested

Q.4

i ) A, C – ball and socket joint

    B, D – hinge joint

ii )

-        vertebrae are linked together by ligaments

-        to form a column

-        allow the attachment of muscles

iii )

-        take in more vit. D to help the absorption of calcium from food

-        take in more calcium for bone formation

-        do regular weight-bearing exercise to stimulate the increase in bone mass