Biology : Locomotion and Movement

In human body, which one of the following is anatomically correct?

• Floating ribs - 2 pairs

• Collar bones - 3 pairs

• Salivary glands - 1 pair

• Salivary glands - 1 pair

Which of the following is a flowering plant with nodules containing filamentous nitrogen-fixing micro-organism

• casuarina equisetifolia

• crotalaria juncea

• cycas revoluta

• cycas revoluta

Which of the following is an example of negative feedback loop in humans?

• constriction of skin blood vessels and contraction of skeletal muscles when it is too cold

• secretion of tears after falling of sand particles into the eye

• salivation of mouth at the sight of delicious food

• salivation of mouth at the sight of delicious food

The contractile protein of skeletal muscle involving ATPase activity is

• tropomyosin

• myosin

• α-actinin

• α-actinin

The pivot joint between atlas and axis is a type of

• Fibrous joint

• Cartilaginous joint

• Synovial joint

• Synovial joint

Out of 'X' pairs of ribs in humans only 'Y' pairs are true ribs. Select the option that correctly represents values of X and Y and provides their explanation :

• X = 12, Y = 7
  True ribs are attached dorsally to vertebral column and ventrally to the sternum

• X = 12, Y = 5
  True ribs are attached dorsally to vertebral column and sternum on the two ends

• X = 24, Y = 7
  True ribs are dorsally attached to vertebral column but are free onventral side

• X = 24, Y = 7
  True ribs are dorsally attached to vertebral column but are free onventral side

A baby boy aged two years is admitted to play school and passes through a dental check-up. The dentist observed that the boy had twenty teeth.
Which teeth were absent?

• Incisors

• Canines

• Pre-molars

• Pre-molars

Which of the following hormones can play a significant role in osteoporosis?

• Aldosterone and Prolactin

• Progesterone and Aldosterone

• Parathyroid hormone and Prolactin

• Estrogen and Parathyroid hormone

Calcium is important in skeletal muscle contraction because it

• Binds to troponin to remove the masking of active sites on actin for myosin.

• Activates the myosin ATPase by binding to it.

• Prevents the formation of bonds between the myosin cross bridges and the actin filament.

• Detaches the myosin head from the actin filament.

Match the items given in Column I with those in Column II and select the correct option given below

• a	b	c	d
  iii	ii	iv	i

• a	b	c	d
  i	ii	iii	iv

• a	b	c	d
  iv	i	ii	iii

• a	b	c	d
  ii	iii	i	iv