Q: When a molecule of pyruvic acid is subjected to anaerobic oxidation and forms lactic acid, there is

\$\textbf{Correct Option A}\$ \$\textbf{Solution}\$ \$\bullet\$ During the process of glycolysis, the glucose is converted into pyruvate and this process occurs in the absence of oxygen it is a anaerobic process.\$\bullet\$ Again in the absence of oxygen when the pyramid is subjected to aerobic oxidation it produces lactic acid by utilizing the three ATP molecules.\$\bullet\$ During this process there is regeneration of two molecules of NADH which is again utilised in the process of glycolysis.\$\bullet\$ We can conclude that during this process there is loss of 3 ATP molecules.\$\bullet\$ So, the correct option is A.

Q: Choose the odd one out in each of the following groups of four items each:Ethyl alcohol, Carbon dioxide, Starch, Oxygen absence

\$\textbf{Solution:}\$ Starch\$\textbf{Explanation:}\$\$\bullet\$ In anaerobic respiration or in fermentation, pyruvate from glucose is converted into alcohol and carbon dioxide in the absence of oxygen.\$\bullet\$ Starch is the odd one out.

Question 1

What are respiratory substrates? Name the most common respiratory substrate.

Accepted Answer

The compounds oxidised during the process of respiration are called as respiratory substrates. Carbohydrates, especially glucose, act as a respiratory substrate. Fats, proteins, and organic acids can also act as respiratory substrates depending upon the physiological condition of the body of an organism.

Question 2

Distinguish between aerobic respiration and fermentation.

Accepted Answer

Aerobic respiration Fermentation 1Oxygen is used for deriving energy.It occurs in the absence of oxygen. 2It occurs in the cytoplasm and mitochondria.It occurs in the cytoplasm. 3End products are carbon dioxide and water.End products are ethyl alcohol and carbon dioxide. 4Complete oxidation of the respiratory substrate takes place. Incomplete oxidation of the respiratory substrate takes place 538ATP molecules are produced during aerobic respiration.Only 2 ATP molecules are produced.

Question 3

Can you tell which metabolic pathway is taking place resulting in the formation of CO$_2$? Where do you think the bacteria for these fermentations came from?

Accepted Answer

In the case of aerobic respiration, during glycolysis, a glucose molecule is converted to two molecules of pyruvate and carbon dioxide. However, if oxygen is not present, fermentation of the pyruvate molecule will occur, which also results in the formation of carbon dioxide. Homolactic fermentation(producing only lactic acid) is the simplest type of fermentation and is the bacterial source.

Question 4

When a molecule of pyruvic acid is subjected to anaerobic oxidation and forms lactic acid, there is

Accepted Answer

$\textbf{Correct&#10;Option A}$ &#10;&#10;$\textbf{Solution}$&#10;&#10;$\bullet$ During the process of glycolysis, the glucose is converted into pyruvate and this process occurs in the absence of oxygen it is a anaerobic process.$\bullet$ Again in the absence of oxygen when the pyramid is subjected to aerobic oxidation it produces lactic acid by utilizing the three ATP molecules.$\bullet$ During this process there is regeneration of two molecules of NADH which is again utilised in the process of glycolysis.$\bullet$ We can conclude that during this process there is loss of 3 ATP molecules.$\bullet$ So, the correct option is A.&#10;&#10;

Question 5

In which one of the following processes $CO_2$ is not released?

Accepted Answer

Aerobic respiration in plants and animals oxidizes the respiratory substrate and produces carbon dioxide and water along with ATP.Anaerobic respiration is a type of respiration which takes place in the absence of oxygen. it is also known as fermentation.Alcoholic fermentation is a type of anaerobic respiration in which the respiratory substrate is converted to carbon dioxide and alcohol along with the production of ATP.Lactate fermentation is a type of anaerobic respiration in which the respiratory substrate is converted into lactate along with the production of ATP. It takes place in muscles during strenuous physical work.So, the correct answer is 'Lactate fermentation'.

Question 6

In alcoholic fermentation

Accepted Answer

Alcoholic fermentation also referred to as ethanol fermentation, is a biological process in which elements, such as glucose, fructose and sucrose are converted into cellular energy and thereby produce ethanol and carbon dioxide as a metabolic waste product. During fermentation, glucose undergoes glycolysis and yields pyruvic acid, which then converted to acetyl CoA. Then glyceraldehyde phosphate is produced, which then converted to acetaldehyde and this acetaldehyde converted into ethanol. So, in alcohol fermentation triose phosphate is the electron donor, while acetaldehyde is the electron acceptor. So, the correct answer is option A.

Question 7

Lactic acid fermentation does not produce

Accepted Answer

In lactic acid fermentation, the 3-carbon pyruvate is converted to the 3-carbon lactic acid. Also NAD$^{+}$ is regenerated in the process, allowing glycolysis to continue to make ATP in anaerobic conditions. Hence lactate and NAD$^{+}$ are the direct products and ATP is the indirect product of lactic acid fermentation. NADH act as a reducing agent here, while CO$_{2}$ is a product of alcohol fermentation.

Question 8

Choose the odd one out in each of the following groups of four items each:Ethyl alcohol, Carbon dioxide, Starch, Oxygen absence

Accepted Answer

$\textbf{Solution:}$ Starch$\textbf{Explanation:}$$\bullet$ In anaerobic respiration or in fermentation, pyruvate from glucose is converted into alcohol and carbon dioxide in the absence of oxygen.$\bullet$ Starch is the odd one out.

Question 9

The main purpose of cellular respiration is to

Accepted Answer

Cellular respiration is the mechanism of breakdown of food materials within the cell to release energy and the trapping of this energy for synthesis of ATP. Therefore, the main purpose is to convert energy stored in the chemical bonds of glucose to energy that the cell can use.So, the correct option is 'Convert energy stored in the chemical bonds of glucose to energy that the cell can use'.

Question 10

The number of ATP produced when a molecule of glucose undergoes fermentation is?

Accepted Answer

The chemical breakdown of glucose in the absence of oxygen is called as fermentation. This process is also called anaerobic respiration. In this reaction, 2 moles of $ATP$ along with 2 molecules of $NADH$ are generated during the conversion of glucose to pyruvate. This pyruvate is then converted into lactic acid at the expenditure of 2 molecules of $NADH$. So the net gain is $2$ $ATP$ molecules.Thus the correct answer is option C.

Revise with Concepts

Cellular Respiration

Fermentation (Anaerobic Respiration)

Learn with Videos

What are respiratory substrates? Name the most common respiratory substrate.

Distinguish between aerobic respiration and fermentation.

Can you tell which metabolic pathway is taking place resulting in the formation of CO $_{2}$ ? Where do you think the bacteria for these fermentations came from?

When a molecule of pyruvic acid is subjected to anaerobic oxidation and forms lactic acid, there is

In which one of the following processes $C O_{2}$ is not released?

In alcoholic fermentation

Lactic acid fermentation does not produce

Choose the odd one out in each of the following groups of four items each:
Ethyl alcohol, Carbon dioxide, Starch, Oxygen absence

The main purpose of cellular respiration is to

The number of ATP produced when a molecule of glucose undergoes fermentation is?

Revise with Concepts

Cellular Respiration

Fermentation (Anaerobic Respiration)

Learn with Videos

What are respiratory substrates? Name the most common respiratory substrate.

Distinguish between aerobic respiration and fermentation.

Can you tell which metabolic pathway is taking place resulting in the formation of CO2​? Where do you think the bacteria for these fermentations came from?

When a molecule of pyruvic acid is subjected to anaerobic oxidation and forms lactic acid, there is

In which one of the following processes CO2​ is not released?

In alcoholic fermentation

Lactic acid fermentation does not produce

Choose the odd one out in each of the following groups of four items each: Ethyl alcohol, Carbon dioxide, Starch, Oxygen absence

The main purpose of cellular respiration is to

The number of ATP produced when a molecule of glucose undergoes fermentation is?

Can you tell which metabolic pathway is taking place resulting in the formation of CO $_{2}$ ? Where do you think the bacteria for these fermentations came from?

In which one of the following processes $C O_{2}$ is not released?

Choose the odd one out in each of the following groups of four items each:
Ethyl alcohol, Carbon dioxide, Starch, Oxygen absence