Tag: respiration

Questions Related to respiration

Which of the following is necessary for respiration in plants?

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Carbon dioxide

  2. Oxygen

  3. Chlorophyll

  4. Light

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Correct Option: B
Explanation:

Oxygen is the final electron electron acceptor in the electron transport chain, which occurs in the mitochondria. So, for aerobic respiration oxygen is must. Respiration decreases with decreased available oxygen. Under circumstances where no oxygen is present, like in poorly draining soil, anaerobic respiration (fermentation) occurs.

If the naked pea seeds are kept in four respiratory flasks, they would germinate best in the flask which contains

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Carbon dioxide

  2. Oxygen

  3. Hydrogen

  4. Nitrogen

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Correct Option: B
Explanation:
Germination is a process of sprouting of seeds which later develops into a new plant. There are several factors which play vital role in the germination process. Theses are water, temperature, oxygen and light. During the process of germination, initially, the seed absorbs water. Later, the swollen seed respires that requires oxygen. Hence, when naked pea seeds are kept in a flask containing oxygen, it shows the best germination. 
Thus, the correct answer is option B.
Identify the correct terms for the given statements and select the correct answer.

(i) Sudden increase in the rate of respiration during ripening of fruits.
(ii) Reduction in the consumption of respiratory substrate when mode of respiration is changed from anaerobic to aerobic
(iii) Respiratory oxidation of carbohydrates and fats.

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Pasteur effect- (i) ; Floating respiration -(ii) ; Climacteric respiration- (iii)

  2. Pasteur effect- (ii) ; Floating respiration -(iii) ; Climacteric respiration- (i)

  3. Pasteur effect- (iii) ; Floating respiration -(ii) ; Climacteric respiration- (i)

  4. Pasteur effect- (ii) ; Floating respiration -(i) ; Climacteric respiration- (iii)

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Correct Option: B

Which one of the following organisms may respire in the absence of oxygen?

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Azotobacter

  2. Clostridium

  3. Rhizobium

  4. Lactobacillus

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Correct Option: B
Explanation:

Obligate anaerobic beings are those that cannot survive when oxygen is present. Some fungi, some bacteria (like the agent of botulism -Clostridium botulinum, and the agent of tetanus- Clostridium tetani) and some protozoans are examples of obligate anaerobes.


For aerobic respiration to occur

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Pyruvate must be transported to the mitochondrion

  2. Oxygen must be available to the mitochondrion

  3. Hydrogen ions released from the breakdown of pyruvate must be carried to the electron transport system

  4. All of the above

Show answer
Correct Option: D
Explanation:

  • Aerobic respiration is the process that takes place in the presence of oxygen.
  • The first part of the process is where the molecule of glucose is broken down to 2 molecules of pyruvate by the process of glycolysis
  • These pyruvate molecules are to enter the mitochondria to under go the reaction of kerb cycle, but the molecule of pyruvate itself cannot enter the mitochondria, it is converted to acetyl CoA so that it can enter inside the mitochondrion membrane.
  • After the kerb cycle molecules of NADH and $FADH _2$are formed which enter the ETS and undergo oxidative phosphorylation.
  • Hydrogen ions are released from the NADH and $FADH _2$ molecules which are transported from inner membrane of mitochondria to the intermembrane matrix of mitochondria, this builds a concentration gradient across the membrane. Also the hydron ions and the electrons that are transported by the complexs of the ETS are in the end accepted by the oxygen molecule forming water that is why it is known as oxidative phosphorylation
  • The concentration gradient that is made is used for the transport of hydronium ions across the ATP synthase complex of the inner mitochrondrial membrane. 
  • With the transport of 2 hydrogen ions one molecule of ATP is formed.
  • Thus glycolysis which takes place in cytoplasm, Kerb cycle that takes place in mitochondria , oxidative phosphorylation and chemisomotic phosphorylation are the parts of aerobic respiration.
  • Therefore the answer 'All of the above' is correct.

















CAM plants are mostly

factors affecting respiration living organisms and energy production life processes in living organisms- part 1 respiration biology

  1. Tropical plants

  2. Succulents

  3. Monocots

  4. Mangroves

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Correct Option: B
Explanation:

CAM (Crassulacean Acid Metabolism) is a pathway of photosynthesis which occurs in desert succulents, which have a low surface-to-volume ratio. In this pathway of photosynthesis carbon is fixed during night time while decarboxylation reaction takes place at day time..

So, the correct option is 'succulents'

Which out of the following addiction is the most harmful for the respiratory system?

zoology respiration effects of smoking smoking tobacco drugs

  1. Smoking

  2. Chewing pan

  3. Chewing gutkha

  4. Alcohol consumption

Show answer
Correct Option: A
Explanation:

Addiction is a phenomenon in which there is physical or psychological need to do, take or use something. The various addictions are smoking, chewing pan, chewing gutkha, alcohol, etc. Out of these addictions, the most harmful addiction for the respiratory system is smoking. It causes respiratory diseases like bronchitis, emphysema, laryngitis, breathlessnes, lung irritation. Its continuous use also causes permanent damage to the alveoli of the lungs. Nicotine is the addictive drug which is used in cigarettes.  

Thus, the correct answer is 'Smoking.'

Which one of the following reactions is an example of oxidative decarboxylation?

biology respiration amphibolic pathway living organisms and energy production life processes in living organisms- part 1

  1. Conversion of succinate to fumarate.

  2. Conversion of fumarate to malate.

  3. Conversion of pyruvate to acetyl Co-A.

  4. Conversion of citrate to isocitrate.

Show answer
Correct Option: C
Explanation:

The conversion of pyruvate to acetyl-CoA is a linker step between glycolysis and Krebs cycle. After the entry of pyruvate in the mitochondria the acetylation takes place in the perimitochondrial space which is the space between the inner and outer mitochondrial membrane. Each molecule of pyruvic acid is oxidatively decarboxylated to acetyl coA by the action of an enzyme complex pyruvate dehydrogenase. The acetyl coA then enters the Krebs cycle.  Thus the correct answer is option C.

The importance of the Kreb's cycle is 

biology respiration amphibolic pathway living organisms and energy production life processes in living organisms- part 1

  1. Production of amino acid

  2. Production of vitamin

  3. Production of ATP molecule through oxidative phosphorylation

  4. ATP formation through oxidative and substrate level phosphorylation

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Correct Option: D
Explanation:

The pyruvic acid enters Krebs cycle in form of acetyl CoA where it is oxidatively decarboxylated into CO$ _2$. The complete Kreb cycle leads to the net formation of 2 molecules of ATP by substrate-level phosphorylation, 8 molecules of NADH plus 2 molecules of FADH$ _2$ (via succinate dehydrogenase). The NADH and FADH$ _2$ then enter the ETS to drive ATP production by substrate level phosphorylation. 

So, the correct answer is option D.

An amphibolic pathway is

biology respiration amphibolic pathway living organisms and energy production life processes in living organisms- part 1

  1. TCA cycle

  2. Calvin cycle

  3. Terminal oxidation

  4. Electron transport chain

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Correct Option: A
Explanation:

Kreb's cycle consists of 8 cyclic steps which take place in the mitochondrial matrix. Each step is catalyzed by a specific enzyme. In Kreb's cycle, the entrant molecule is 2- carbon acetyl coenzyme A and the receptor molecule is 4- carbon oxaloacetate. Since the process involves both catabolic and anabolic reactions. it is an amphibolic pathway. It degrades acetyl coenzyme A and yields carbon dioxide and energy which is used to produce NADH, H+, and FADH+

Thus, the correct answer is option A.