Tag: carbohydrate metabolism

Questions Related to carbohydrate metabolism

One molecule of NADH$ _{2}$ on oxidation yields ............... ATP molecules.

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. One

  2. Two

  3. Three

  4. Four

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Correct Option: C
Explanation:
The NADH$ _2$ and the FADH$ _2$ are produced during the cycles of respiration. These molecules are produced during the glycolysis and the Krebs cycle. These molecules are oxidized in the process of electron transport system. This is the system in which the electrons is donated from one donor to acceptor. These products are oxidized and the protons are used for creating a gradient which is used in the synthesis of ATP. NADH$ _2$ transfers the electrons to the complex I and then transfers the electrons to the complex II. This results in more number of protons which are pumped by ATP synthase. So, the more protons will result in the production of 3 ATPs.
Thus, the correct answer is option C. 

The amount of energy the earth receives from the sun per year is

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $15 \times 100^{20} kcal$

  2. $10 \times 10^{30} kcal$

  3. $15 \times 10^{20} kcal$

  4. $15 \times 10^{25} kcal$

Show answer
Correct Option: C
Explanation:

The sun is considered as the major source of energy. The solar energy is the renewable form of energy and is used for various purposes like generating electricity, working of the solar batteries, etc. The total amount of the energy which is received by the earth from the sun is equal to about 15×10$^{20}$ kcal.

Thus, the correct answer is option C. 

The total amount of energy released from one molecule of glucose on oxidation is about 

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $1600 kJ$

  2. $2300 kJ$

  3. $2500 kJ$

  4. $2900 kJ$

Show answer
Correct Option: D
Explanation:

The glucose molecule is oxidised to form pyruvic acid which is further oxidised to release water and carbon dioxide. When one glucose molecule is completely oxidised, 38 ATP molecules are formed. The energy of the 38 ATP is equal to about 2900 kJ or 686 kcal of energy. The equation of the glucose oxidation is given as 

C$ _6$ H$ _{12}$ O$ _6$ + 6O$ _2$ $\rightarrow$ 6CO$ _2$ + 6H$ _2$O + 2900 kJ energy
Thus, the correct answer is option D. 

How much of the energy released during aerobic respiration is approximately conserved in the form of ATP?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. $20\%$

  2. $40\%$

  3. $60\%$

  4. $100\%$

Show answer
Correct Option: B
Explanation:

Aerobic respiration is a breakdown of organic material in the presence of oxygen. It takes place in the cytoplasm and mitochondria of the cell. During aerobic respiration, the first step is glycolysis in which there is a net formation of eight molecules of ATP and then the link reaction in which the pyruvic acid which is the end product of glycolysis is converted into acetyl CoA. 

This reaction leads to the formation of six molecules of ATP but these are not included in the Krebs cycle. This is acetyl CoA enter the Krebs cycle, which results in the formation of 30 molecules of ATP.
So, the net formation of ATP is 38 ATP and this round off to 40% of the total energy that is conserved as ATP.
So, the correct option is '40%'

The synthesis of ATP in photosynthesis and respiration is essentially an oxidation-reduction process involving removal of energy from 

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Oxygen

  2. Phytochrome

  3. Cytochrome

  4. Electrons

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Correct Option: D
Explanation:

Synthesis of ATP in photosynthesis as well as respiration is possible by the help of several oxidation and reduction reactions. This can be termed as redox reactions. This involves the excitation of electrons from ground state to excited state and vice - versa. ATP is called as the energy currency of cell.

Which one of the following is energy currency of the cell?

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. Phosphate

  2. ATP

  3. ADP

  4. AMP

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Correct Option: B
Explanation:

The major energy currency molecule of the cell is ATP. This complex  molecule is critical for all life froms, the simplest to the most complex. It is one of the end products of photophosphorylation, cellular respiration and fermentation and used by enzymes and structural proteins in many cellular processes.

In photosynthesis energy from light reaction to dark reaction is transferred in the form of 

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. ADP

  2. ATP

  3. RUDP

  4. Chlorophyll

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Correct Option: B
Explanation:

ATP is the energy currency. Assimilatory power is the power of plants in the form of ATP and NADPH to obtain food in the form of carbohydrates from the reduction of $CO _2$ during photosynthesis.

Usable energy available from respiration is

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. 10%

  2. 30%

  3. 40%

  4. 50%

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Correct Option: D
Explanation:

One mole of glucose on complete oxidation to carbon dioxide and water produces about 690,000 calories. About 10,000 calories are needed to form the high energy phosphate bonds in one mole of ATP. 36 or 38 moles of ATP formed in respiration process will trap 360,000 or 380,000 calories. The remaining 330, 000 or 310,000 calories are lost as heat. Thus about 52% of the energy released from glucose is trapped in ATP. 

Thus, the correct answer is option D. 

Number of ATP molecules formed during complete oxidation of fructose 1, 6-diphosphate is 

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. 20

  2. 32

  3. 36

  4. 40

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Correct Option: D
Explanation:

Fructose-1, 6-bisphosphate is formed during glycolysis as an intermediate product when glucose-1,6-bisphosphate is converted into fructose-1, 6-bisphosphate and enzme phosphofructokinase is used for this. Fructose generally results in the formation of a higher amount of energy after oxidation and in this case, it is more than glucose.

So, the correct option is '40'

The net gain of energy from one gram mole of glucose during aerobic respiration is

bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

  1. 2 ATP

  2. 4 ATP

  3. 38 ATP

  4. 40 ATP.

Show answer
Correct Option: C
Explanation:

If a cell is undergoing aerobic respiration then it will first undergo glycolysis which is the first breakdown of glucose in the cell and then Krebs cycle.

The net gain of ATP in glycolysis is 8 and the net gain of ATP in Krebs cycle including the substrate phosphorylation and oxidative phosphorylation is 30. So, the total gain of ATP is 38 from one molecule of glucose.
So, the correct option is '38 ATP'