Questions

DNA is a double-stranded molecule twisted into a helix. The shape of DNA is a double helix, which is like a twisted ladder. The sides of the ladder are made of alternating sugar and phosphate molecules. Deoxyribose, which is a pentose, and a phosphate group are the two molecules together form the two sides of the DNA. The rungs of the ladder are pairs of 4 types of nitrogen bases.

Envelope is a letter holder for one letter and in the question it mean that it holds one letter. Eye is also a word which starts and end with E but has one letter in the middle.

Hence, soil erosion on hillslopes can be checked by Terrace cultivation.

Endocrine glands are glands of the endocrine system that secrete their products, hormones, directly into the blood rather than through a duct.

The major glands of the endocrine system include:

pineal gland,

pituitary gland,

pancreas,

ovaries,

testes,

thyroid gland,

parathyroid gland,

hypothalamus and

adrenal glands.

Spalling hammer is used for Rough dressing of stones.