Locomotion and Movement

Myosin head separates from actin when

Assertion : $\mathrm{Na}$ and $\mathrm{K}$ ions are necessary for muscle contraction. Reason : $\mathrm{Na}$ and $\mathrm{K}$ concentration changes across the muscle cell membrane resulting in development of potential…

Acidic $\mathrm{pH}$ of muscles is due to

Total number of bones in the hindlimb of a man is

A cricket player is fastly chasing a ball in the field. Which one of the following groups of bones are directly contributing in this movement?

Assertion : On stimulation, a muscle cell releases calcium ions $\left(\mathrm{Ca}^{2+}\right)$ from sarcoplasmic reticulum. Reason : By reacting with a protein complex, $\mathrm{Ca}^{2+}$ uncover active sites on the…

Achondroplasia is a disease related with the defect in the formation of

Pacinian corpuscles occur in the skin of certain parts of body in mammals. These are

Assertion : In a pivot joint, rounded or pointed bone fits into a shallow depression in another bone. Reason: Pivot joints are present between the metacarpals and phalanges of the fingers.

During muscular contraction, which of the following events occur? (i) H-zone disappears (ii) A band widens (iii) I band reduces in width (iv) Width of A band is unaffected (v) M line and $Z$ line come closer.

Which one of the following is a sesamoid bone?

The shoulder blade is made of