Which carbohydrate is an essential constituent of plant cells?
Starch
Cellulose
Sucrose
Vitamins
The activation energy for a simple chemical reaction A → B is Ea in forward direction. They activation energy for reverse reaction
is negative of Ea
is always less than Ea
can be less than or more than Ea
is always double of Ea
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 Ea obtained in laboratory
cannot say anything
Enzymes are made up of
edible proteins
proteins with specific structure
nitrogen contaning carbohydrates
carbohydrates
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.
C.
It is also present in rain water.
Vitamm-B12 is chemically cyanocobalamin. It contains Co metal. All vitamins including vitamin-B12 are required in very small amounts. Neither plants nor animals are independently capable of constructing vitamin-B12. Vitamm B12 is only synthesised by bacteria as only they have enzymes necessary to synthesise vitamin B12. Vitamin-B12 is not present in rain water.
Which of the following food-stuffs contains nitrogen?
Carbohydrates
fats
Proteins
None of these