Food sometimes enters the wind pipe and causes choking. How does it happen ?

How does sperm enter ovum?

How does food get its taste?

Blood is filtered in Bowman's capsule of nephron. For the filtration of blood some pressure is needed. How does this pressure happen to blood ?

How does CO_2 enter into leaf?

Velocity-time graph for the motion of a certain body is shown in Fig. Explain the nature of this motion. Find the initial velocity and acceleration and write the equation for the variation of displacement with time. What happens to the moving body at point B? How does the body move after this moment ?