When a biochemical reaction is carried out in laboratory from outside of human body in the absence of enzyme than rate of reaction obtained is 10^-6 times, then activation energy of reaction in the presence of enzyme is

• 6/RT

• P is required

• different from E_a obtained in laboratory

• cannot say anything

Which of the following statements about vitamin B₁₂ is incorrect?

• It has a cobalt atom.

• It also occurs in plants.

• It is also present in rain water.

• It is needed for human body in very small amounts.

Which of the following is not present in nucleic acids?

• Uracil

• 2-aminopyridine

• Thymine

• Adenine

Enzymes are made up of

• edible proteins

• proteins with specific structure

• nitrogen contaning carbohydrates

• carbohydrates

The deficiency of vitamin -B₁ causes

• beri-beri

• scurvy

• rickets

• anaemia

Glucose is obtained from

• Starch

• Molasses

• Both (a) and (b)

• None of these

Which of the following food-stuffs contains nitrogen?

• Carbohydrates

• fats

• Proteins

• None of these

Which carbohydrate is an essential constituent of plant cells?

• Starch

• Cellulose

• Sucrose

• Vitamins

The activation energy for a simple chemical reaction A → B is E_a in forward direction. They activation energy for reverse reaction

• is negative of E_a

• is always less than E_a

• can be less than or more than E_a

• is always double of E_a

Which compound is not a lipid?

• Lecithin

• Lysine

• Cerebroside

• Cephalin