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:

The contractile protein of skeletal muscle involving ATPase activity is:

Gout is a type of disorder which leads to:

Match List I with List II: List I A. Fibrous joints B. Cartilaginous joints C. Hinge joints D. Ball and socket joints List II I. Adjacent vertebrae, limited movement II. Humerus and Pectoral girdle, rotational movement III. Skull, don't allow any movement IV. Knee, help in locomotion

Three types of muscles are given as a, b and c. Identify the correct matching pair along with their location in human body:

Given below are two statements: Assertion (A): Osteoporosis is characterised by decreased bone mass and increased chances of fractures. Reason (R): Common cause of osteoporosis is increased levels of estrogen. In the light of the above statements, choose the most appropriate answer from the options given below:

Which one of the following pairs of chemical substances is correctly categorised?

Select the correct statement regarding the mechanism of muscle contraction.

Calcium is important in skeletal muscle contraction because it: