Tag: metabolism

Questions Related to metabolism

It is much easier for a small animal to run uphill than for a large animal, because - ?

bio-chemistry organization of life concept of metabolism metabolism in animals metabolism

  1. small animals have lower $O _2$ requirement

  2. the efficiency of muscles in larger animal is less than in smaller animal

  3. it's easier to carry a small body weight

  4. smaller animals have higher metabolic rate

Show answer
Correct Option: D
Explanation:
It has been observed that the metabolic rate of an organism is inversely proportional to its body weight, that is smaller animals have a higher metabolic rate. This higher metabolic rate allows them to have higher energy and are quicker in climbing heights as compared to larger animals.

So, the correct answer  is 'smaller animals have higher metabolic rate'.

Choose the correct answers from the alternatives given .
All the biochemical pathways in a cell constitute

bio-chemistry organization of life concept of metabolism metabolism in animals metabolism

  1. Coupling reactions

  2. Endergonic reactions only

  3. Exergonic reactions only

  4. Metabolism

Show answer
Correct Option: D
Explanation:

There are various biochemical reactions taking inside a cell. Some of these reactions may result in absorption of energy (called as endergonic reactions) or release of energy (called as exergonic reactions). Often both these types of reactions are coupled, to get the energy to those endergonic reactions, they are paired up with energy-releasing exergonic reactions (known as coupling reactions). Although, there are a wide variety of reactions taking place inside the body apart from these reactions. Metabolism is a term that is used to describe all these biochemical reactions involved in maintaining the living state of the cells and the organism. 

So, the correct option is 'Metabolism'.


In a reaction, reactants form a transition state, before the formation of products. Which of the following is affected by the action of enzyme?

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Products only

  2. Reactants only

  3. Transition state only

  4. Products and reactants

  5. Transition state and products

Show answer
Correct Option: C
Explanation:

Any chemical reaction includes the formation of transition state between reactant and product. Formation of transition state requires high energy content of reactant molecules for alignment of reacting groups, the formation of transient unstable charges, rearrangements of chemical bonds etc. The energy required for formation of the transition state is termed as activation energy. Enzymes enhance the rate of reaction by lowering down the activation energy of transition state. Thus, the correct answer is option C.

An enzyme increases the rate of a reaction by?

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. enzymes speed up reactions by lowering activation energy.

  2. Increasing the rate of random collisions of molecules

  3. Removing the product of the reaction so allowing it to continue

  4. Bringing the reacting molecules into precise orientation with each other

Show answer
Correct Option: A
Explanation:


  • Enzymes provide activation energy for the reactions they catalyze.
  • Catalysts lower the activation energy for reactions. 
  • The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.so, option A is correct.

Biochemical reactions are carried out by enzymes

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. By decreasing the energy of the reactants

  2. By increasing the activation energy of the reaction

  3. By decreasing the activation energy of the reaction

  4. By increasing the energy of the products of the reaction

  5. By decreasing the energy of the products of the reaction

Show answer
Correct Option: C
Explanation:

Any chemical reaction includes the formation of transition state between reactant and product. The energy required for formation of the transition state is termed as activation energy. Enzymes enhance the rate of reaction by lowering down the activation energy of transition state. Thus, the correct answer is option C.

Energy released from enzyme-substrate interaction is

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Activation energy

  2. Binding energy

  3. Constant energy

  4. Variable energy

Show answer
Correct Option: B
Explanation:

The transition state is the state of the activated complex which is highly unstable and readily changes into the product.  At the transition state, the enzyme attaches to the substrate to form an enzyme-substrate complex by forming a weak chemical bond. Binding energy is the free energy that is released by the formation of weak interactions between a complementary substrate and enzyme.

So, the correct answer is option B.

Chemical reactions require energy for

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Oxidation

  2. Entropy

  3. Activation

  4. Enthalpy

Show answer
Correct Option: C
Explanation:

Chemical reactions take place mainly at a specific temperature in presence of a catalyst. The substrate and product have different energy state. The energy gap between the substrate and the product is known as activation energy which is the minimum energy required to initiate a reaction. In presence of a catalyst, the activation energy lowers and the substrate changes into the product.

So, the correct answer is option C.

Energy required for start of a chemical reaction is

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Activation energy

  2. Entropy

  3. Potential energy

  4. Kinetic energy

Show answer
Correct Option: A
Explanation:
Entropy is a measure of thermal energy.
Potential energy is the energy stored in an object at a particular height.
Kinetic energy is the energy stored in an object in motion.
Enzymes are proteins which accelerate the rate of the reaction. The substrate and product have different energy state. The energy gap between the substrate and the product is known as activation energy which is the minimum energy required to initiate a reaction. The enzymes lower the activation energy and lead to the faster conversion of substrate to the product.
So, the correct answer is option A.

Activation energy is required for :

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Bringing reactants together

  2. Destabilisation of bonds of reactants.

  3. Both A and B

  4. None of the above

Show answer
Correct Option: C

Enzymes increase the rate of biochemical reaction through 

biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

  1. Changing equilibrium

  2. Lowering activation energy

  3. Forming reactant-product complex

  4. Forming enzyme-product complex.

Show answer
Correct Option: B
Explanation:

Enzymes are biological catalysts. A catalyst is a chemical that increases the rate of a chemical reaction without itself being changed by the reaction. Without a catalyst, the amount of energy required for the reaction is large. Enzymes and catalysts both affect the rate of a reaction. The lower the activation energy for a reaction, the faster the rate of chemical reaction. Thus enzymes speed up reactions by lowering activation energy.

So, the correct answer is option B.