Biology Test 260

The volume of the air inspired or expired during a normal respiration is called tidal volume. This is about 500 mL.

Under normal physiological conditions, about 5 mL oxygen can be delivered to the tissues by 100 mL of blood.

Corpus collosum connects two cerebral hemispheres. It is a large bundle of myelinated fibres.

The internal stimuli like hunger, thirst, etc., are received by interoceptors. These are located within the organs of the body other than muscles, tendons and joints.

The iris controls the amount of light entering the eye by the radial muscles contracting in dim light and the circular muscles contracting in bright light.

In angiosperms, functional megaspore develops as a result of free nuclear division into embryo sac.

Among the given statements, only statement (c) is incorrect about oogenesis. The growth phase of the oogenesis is comparatively longer than the growth phase of spermatogenesis.

During the complete development of the male gametophyte from pollen mother cell, one meiotic and two mitotic cell divisions are necessary.

The barrier method of birth control includes diaphragms. These methods work by stopping sperm from entering the vagina.

The most widely accepted method of contraception in India, in which a small piece of plastic or metal device is placed in uterus is IUDs. It’s a long term reversible and one of the most effective birth control methods.