The helical structure of proteins is stabilised by

• peptide bonds

• dipeptide bond

• hydrogen bond

• van der Waal's forces

Carbohydrates are stored in human body as

• glucose

• glycogen

• starch

• fructose

Proteins are hydrolysed by enzymes to give

• dihydroxy acids

• amino acids

• amines

• carboxylic acids

DNA contains the sugar

• Deoxyribose

• Ribose

• D-fructose

• D-glucose

Lactose sugar is formed from

• d-galactose

• d-glucose

• d-galactose and d-glucose

• d-glucose and d-fructose

Number of peptide bonds in dipeptide is

• 2

• 1

• 3

• 4

Blood sugar is

• fructose

• maltose

• haemoglobin

• glucose

Observe the following statements.

I. Sucrose has glycosidic linkage.

II. Cellulose is present in both plants and animals.

III. Lactose contains D-galactose and D-glucose units.

Which of the following statements are correct?

• (I), (II) and (III)

• (I) and (II)

• (II) and (III)

• (I) and (III)

Identify the statement which is not correct from the following.

(i)Carbohydrates are stored as glycogen in animals.

(ii) In glycylalanine, CO of peptide bond belongs to alanine.

(iii) Base - sugar- phosphate unit is known as nucleoside.

(iv) Obesity is due to hypothyroidism.

The correct answer is:

• i, iv

• ii, iii, iv

• i, iii, iv

• ii, iii

Vitamin-B₁₂ contains

• CO

• Fe

• Zn

• Ca