The saliva from the salivary gland of silkworm is the component of silk and is produced by the larva of the silkworm (cocoon). The Chinese silkworm (B. mori) has been used in commercial silk production for centuries. The adult, which has a wingspan of about 2 in. (50 mm) and a thick, hairy body, lives only two or three days. The female lays 300–500 eggs. The pale, naked larvae fed on mulberry leaves until pupation begins, when they are about 3 in. (75 mm) long. They spin a cocoon of one continuous white or yellow silken thread, about 1,000 yards (900 m) long. The pupa is killed with hot air or steam to preserve the thread intact.

Correct Option: C

The saliva from the salivary gland of silkworm is the component of silk and is produced by the larva of the silkworm (cocoon). The Chinese silkworm (B. mori) has been used in commercial silk production for centuries. The adult, which has a wingspan of about 2 in. (50 mm) and a thick, hairy body, lives only two or three days. The female lays 300–500 eggs. The pale, naked larvae fed on mulberry leaves until pupation begins, when they are about 3 in. (75 mm) long. They spin a cocoon of one continuous white or yellow silken thread, about 1,000 yards (900 m) long. The pupa is killed with hot air or steam to preserve the thread intact.

Inbreeding leads to the expression of recessive characters, most of the time which are harmful.

Correct Option: B

Inbreeding leads to the expression of recessive characters, most of the time which are harmful.

The growing of grass or legumes in rotation with grain or tilled crops as a soil conservation measure is called Ley farming.

Correct Option: A

The growing of grass or legumes in rotation with grain or tilled crops as a soil conservation measure is called Ley farming.

Vector DNA are the DNA molecules that can carry a foreign DNA segment and replicate inside the host cells. Vector DNA may be plasmids, a bacteriophage, cosmids, yeast artificial chromosomes.

Correct Option: B

Vector DNA are the DNA molecules that can carry a foreign DNA segment and replicate inside the host cells. Vector DNA may be plasmids, a bacteriophage, cosmids, yeast artificial chromosomes.

All other are diploid. Best method of haploid plant culture is pollen grain culture.

Correct Option: C

All other are diploid. Best method of haploid plant culture is pollen grain culture.