Tag: carbohydrate metabolism

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Questions Related to carbohydrate metabolism

Multiple choice bio-chemistry carbohydrate metabolism metabolism enzymes metabolism, cell respiration, and photosynthesis

Dark reaction is a

  1. Anabolic

  2. Catabolic

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The anabolic processes are the reactions in which the smaller organic molecules are used for the production of the large complex molecules. The carbon dioxide molecule is fixed in the dark reactions for the formation of the glucose molecule. Six molecules of CO$ _2$ are fixed to form one molecule of glucose in which the energy is stored. 

Thus, the correct answer is option A. 

Multiple choice bio-chemistry carbohydrate metabolism metabolism enzymes metabolism, cell respiration, and photosynthesis

What are biochemical reactions in the body known as?

  1. Anabolic reactions

  2. Metabolic reactions

  3. Catabolic reactions

  4. Vital reactions
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
All the chemical processes which sustain life. (all cells) Sum of all the chemical reactions that take place in the body, consisting of  anabolism and catabolism. Cellular metabolism refers specifically to the chemical reactions within cells. So, the correct option is "B" (Metabolic reactions).
Multiple choice bio-chemistry carbohydrate metabolism metabolism enzymes metabolism, cell respiration, and photosynthesis

Which reactions usually release energy that is used to drive chemical reactions.

  1. Anabolic

  2. Catabolic

  3. Photosynthesis

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Metabolism refers to series of reactions wherein product of one reaction becomes reactant for the next one. It includes catabolism (degradative pathways) and anabolism (synthetic pathways). Catabolic reactions are the reactions in which complex molecules are broken down into smaller simpler molecules. The catabolic reactions are exergonic reactions( energy releasing reactions). While photosynthesis is an anabolic reaction which requires energy for the formation of complex molecules. Hence option B is the correct answer.

Multiple choice bio-chemistry carbohydrate metabolism metabolism enzymes metabolism, cell respiration, and photosynthesis

The term metabolism indicates a variety reactions carried out at

  1. atomic level

  2. molecular level

  3. cellular level

  4. tissue level
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The metabolism is a chemical processes that occur within a living organism in order to maintain life and basic unit of life is cell, hence all metabolic reactions occur  in cell. So, the correct option is 'Cellular level'

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

The enzymes ribulose biphosphate carboxylase-oxygenase and phosphoenol pyruvate carboxylase are activated by

  1. Mg

  2. Zn

  3. Mo

  4. Mn
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Both RUBISCO and PEP carboxylase are important enzymes of dark reaction of photosynthesis. RUBISCO catalyzes carboxylation in C3 plants. In the presence of magnesium activated RUBISCO, carbon dioxide combines with ribulose bis phosphate to form phosphoglyceric acid. In C4 plants, mesophyll cells fix carbon dioxide with the help of phospho enol pyruvate in the presence of magnesium activated phospho-enol pyruvate carboxylase.

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

Haemoglobin is composed of four subunits. When one subunit binds to oxygen, it increases the chances that the other three subunits will also bind to oxygen. What is this type of activity called?

  1. Inhibition

  2. Cooperativity

  3. Enzyme substrate complex

  4. Catalysis

  5. Activation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. When the binding of chemical shuts off the enzymatic activity, the process is called inhibition.
B. When binding of a molecule to the enzyme increase its affinity for more molecules, it is called cooperativity.
C. Binding of the substrate to the active site of enzyme produces a highly reactive short lived complex called Enzyme substrate complex which breaks into chemical products and unchanged enzyme.
D. Catalysis is the increase in rate of reaction by a catalyst.
E. Activation is the start of reaction by an enzyme.
Hence, the increase in affinity of haemoglobin for oxygen by binding of one oxygen molecule, is cooperativity.
So, the correct answer is 'Cooperativity'.
Multiple choice biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

Cyanide causes irreversible inhibition of cytochrome oxidase. This is because it

  1. Combines with iron.

  2. Destroys tertiary structure.

  3. Attaches to copper.

  4. All the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Cyanide inhibits cytochrome oxidase by combining with Iron within the enzyme which results in the prevention of transport of electrons from cytochrome oxidase to oxygen. So, the correct answer is A.
Multiple choice biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

Which statement regarding enzyme inhibition is correct?

  1. Competitive inhibition occurs when a substrate competes with enzyme for binding to inhibitor protein

  2. Competitive inhibition occurs when the substrate and the inhibitor compete for active site on the enzyme

  3. Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate

  4. Non-competitive inhibitors often bind to the enzyme irreversibly
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A molecule similar to substrate competes with the substrate for active site. Such molecules are known as inhibitor. The presence of the inhibitor decreases availability of the active site for the substrate and further decreases the rate of reaction. This inhibition is known as competitive inhibition.
For example, malonate acts as a inhibitor which  competes with the succinate and prevents its attachment to the enzyme succinate dehydrogenase.
So, the correct answer is option B.
Multiple choice biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

An enzyme brings about

  1. Decrease in reaction time

  2. Increase in reaction time

  3. Increase in activation energy

  4. Reduction in activation energy
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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 D.

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

Nerve gas (DFP) inhibits neurotransmission as it reacts with

  1. Serine of acetylcholine-esterase.

  2. Choline of acetylcholine-esterase.

  3. Acetylcholine.

  4. Noradrenaline.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Nerve gas attacks the nervous system of the human body. All such gases function in the same way, it inhibits the enzyme acetylcholine esterase by reacting with the active site of serine, and is responsible for the breakdown of the acetylcholine in the synapse.
So, the correct answer is A.