Anaerobic respiration

WHAT IS RESPIRATION

Respiration is defined as *The oxidation-reduction processes which occurs inside the living cell in which Organic food molecule is broken down and energy is released which used in performing different functions in body.

Respiration is energy releasing process.

Respiration is divided into two types : 1)Aerobic respiration 2)Anaerobic respiration

In previous blogs we have study respiration and aerobic respiration in detail ,Now in this blog we will study anaerobic respiration in detail with equations.

ANAEROBIC RESPIRATION:

The incomplete broken down of food molecule in absence of oxygen.

It is also called as Fermentation.

It take place in both Prokaryotes (microorganisms) and Eukaryotes(In muscle cells).

This respiration reaction produce less energy.

There are two pathways of anaerobic respiration depending upon nature of final product;

1)Lactic acid fermentation 2)Alcoholic fermentation

1)LACTIC ACID FERMENTATION:

This form of fermentation occurs in muscle cell of human beings and in many microorganisms.

In this fermentation process *Glycolysis* followed by the reduction of pyruvate by NADH into Lactic acid.

This pathway is operates anaerobically because after NADH transfers electron to pyruvate ,Its free to return back and pick up more electrons during the earlier reaction of *Glycolysis*.

1st step:

GLUCOSE + 2 ATP = PYRUVIC ACID + 4 ATP

2nd step:

PYRUVIC ACID 2(C3H4O3) + 2NADH = 2(C3H6O3)(LACTIC ACID) + 2 NAD

2)ALCOHOLIC FERMENTATION;

This fermentation occurs in Microrganisms.

This fermentation also occurs in 2 steps.

In first step is same as Glycolysis during wgich glucose is broken down into 2 molecules of pyruvate and NAD is reduced to NADH2.

In second step NADH2 gives hydrogen to pyruvate and pyruvate reduced which convert into ethyl Alcohol and CO2.

This fermentation is called Alcoholic fermentation because Alcohol produced at end.

1st step:

GLUCOSE + 2 ATP = PYRUVIC ACID + 4 ATP

2nd step:

2(C3H4O3)(PYRUVIC ACID ) = ACETALDEHYDE + 2CO2

ACETALDEHYDE + 2NADH = ETHYL ALCOHOL 2(C2H5OH) + ATP

In these two fermentation Total 4 ATP are produced but 2 ATP also used in Glycolysis investment phase therefore net gain of these two reaction is 2 ATP from one glucose molecule.

It produce less energy than aerobic respiration but it still important because it takes less time than aerobic respiration.

IMPORTANT MCQS IN THIS TOPIC:

1-Which type of fermentation also occurs in Humans:

Answer: LACTIC ACID FERMENTATION

2-The net gain of ATP molecules in anaerobic respiration is :

Answer: 2 ATP

3-Pyruvate is _in anaerobic respiration:

Answer: REDUCED

4-Lactic acid molecule has _Carbons:

Answer: 4 CARBONS

5-Anaerobic respiration occurs in absence of _;

Answer: OXYGEN