Question

Match the following and choose the correct answer.

Hermaphrodite	Produces blood cells and haemoglobin
Direct development	Testis and ovary in the same animal
Chemoreceptor	Larval form absent
Blood gland in earthworm	Sense of chemical substance

a. A-(ii); B-(iii); C-(iv); D-(i)
b. A-(iii); B-(ii); C-(iv); D-(i)
c. A-(i); B-(iii); C-(ii); D-(iv)
d. A-(ii); B-(iv); C-(iii); D-(i)

Answer 1

The proteins and glycoproteins that bind to give signals to molecules are called receptors which were initially named as messengers or ligands. A chemical response is released by the receptors to induce cell growth. There are most of the animals like earthworms, tunicates, snails which are hermaphrodites. Direct development is a form of reproduction with some exceptional features. There are 4-6 segments of blood glands in the earthworm.

Complete answer:
When testis and ovaries are present in the same animal then it is called hermaphrodite. There are only some animals that are hermaphrodite. For example – slugs, some species of fish, etc. Some of the plants also show hermaphroditism. Only 5% approx. animals’ species are hermaphrodite.

The widespread of an alternate mode of reproduction in living amphibians without the larval stage is called direct development. It is the development of an embryo into a mature individual with no larval stage. Metamorphosis is absent from indirect development.
For example – fishes, reptiles, birds, etc.

The sense of chemical substance or specialized sensory receptor cell that can transduce a chemical substance is called chemoreceptor. It is used to generate a biological signal. In the environment, some insects can sense chemical substances. For example – taste buds present in the mouth and sensitive to chemicals, carotid bodies, and aortic goodies.

There are blood glands present in the earthworm on the 4th, 5th, and 6th segments, and blood cells and hemoglobins are also produced which is dissolved in the plasma of blood.

Hence, the correct answer is option (A).

Note: The chemoreceptors help in signaling the body for different reactions. Hermaphrodite animals produce a new offspring for which fertilization takes place in a single body of an animal. The larval stage is not necessary for the direct development process. In earthworms, blood glands are present which are phagocytic.