3.2 Respiration

Question 1

What is the primary purpose of respiration in living organisms?

Answer 1

The primary purpose of respiration is to convert biochemical energy from nutrients into ATP, and to release waste products.

Question 2

True or False: Respiration occurs only in the presence of oxygen.

Answer 2

False

Question 3

What are the two main types of respiration?

Answer 3

Aerobic respiration and anaerobic respiration.

Question 4

Fill in the blank: The process of breaking down glucose in the presence of oxygen is called __________.

Answer 4

aerobic respiration

Question 5

What is the chemical equation for aerobic respiration?

Answer 5

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

Question 6

What is produced during anaerobic respiration in yeast?

Answer 6

Ethanol and carbon dioxide.

Question 7

Multiple Choice: Which of the following is NOT a product of aerobic respiration? A) ATP B) Lactic Acid C) Carbon Dioxide D) Water

Answer 7

B) Lactic Acid

Question 8

What is lactic acid fermentation?

Answer 8

A process where glucose is converted into lactic acid and ATP in the absence of oxygen.

Question 9

True or False: Mitochondria are known as the powerhouse of the cell.

Answer 9

True

Question 10

What is the role of oxygen in aerobic respiration?

Answer 10

Oxygen acts as the final electron acceptor in the electron transport chain.

Question 11

Fill in the blank: The Krebs cycle takes place in the __________ of the mitochondria.

Answer 11

matrix

Question 12

What is the main function of the electron transport chain?

Answer 12

To produce ATP through oxidative phosphorylation.

Question 13

Multiple Choice: Which of the following processes occurs in the cytoplasm? A) Krebs Cycle B) Glycolysis C) Electron Transport Chain D) None of the above

Answer 13

B) Glycolysis

Question 14

What is the net gain of ATP from glycolysis?

Answer 14

2 ATP molecules.

Question 15

True or False: Anaerobic respiration produces more ATP than aerobic respiration.

Answer 15

False

Question 16

What is the main difference between aerobic and anaerobic respiration?

Answer 16

Aerobic respiration requires oxygen while anaerobic respiration does not.

Question 17

Fill in the blank: The waste product of anaerobic respiration in muscle cells is __________.

Answer 17

lactic acid

Question 18

What is the role of NADH in respiration?

Answer 18

NADH donates electrons to electron carriers -> energy gradient formed -> forming the electron transport chain.

Question 19

Multiple Choice: Which stage of respiration produces the most ATP? A) Glycolysis B) Krebs Cycle C) Electron Transport Chain D) Oxidative Phosphorylation

Answer 19

D) Oxidative Phosphorylation

Question 20

What is fermentation?

Answer 20

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.

Question 21

True or False: The total yield of ATP from one molecule of glucose during aerobic respiration is approximately 36-38 ATP.

Answer 21

True

Question 22

What is the role of FADH2 in respiration?

Answer 22

FADH2 donates electrons to electron carriers that donates electrons to the electron transport chain.

Question 23

Fill in the blank: The first step of respiration, glycolysis, occurs in the __________.

Answer 23

cytoplasm

Question 24

What is the significance of the inner mitochondrial membrane?

Answer 24

It contains the proteins and complexes necessary for the electron transport chain.

Question 25

Multiple Choice: Which of the following is a product of the Krebs cycle? A) Glucose B) NADH C) Lactic Acid D) Ethanol

Answer 25

B) NADH

Question 26

What is oxidative phosphorylation?

Answer 26

A cellular process where the energy released during the oxidation of molecules (like NADH and FADH2) is used to generate ATP, the main energy currency of the cell, through a series of electron transfers in the electron transport chain, ultimately reducing oxygen to water.

Question 27

What is the General Process of Oxidation Phosphorylation?

Answer 27

1) NADH and FADH2 donate to electron carriers 2) Electron Transport Chain / Energy Gradient, energy pumps H+ out 3) Proton Gradient and Proton Motive Force, drive H+ in 4) Thru Hydrophilic Channel in stalk particle, ATP synthase use energy to phosphorylate ADP (+ iP) to ATP 5) electrons flow down ETC, O2 final electron acceptor, H+ from matrix reduce O2 to H2O

Question 28

How many ATP molecules do 1 molecule of NADH and FADH produce in oxidation phosphorylation?

Answer 28

Each reduced NAD (NADH) molecule potentially produced (2.5) 3 molecules of ATP. Each reduced FAD (FADH) molecule potentially produced (1.5) 2 molecules of ATP. (All: 32 to 38 ATP)

Question 29

What is the Total ATP generated from Oxidative Phosphorylation?

Answer 29

Each molecule of glucose yields 6 reduced NAD (NADH) from Krebs Cycle + 2 reduced NAD (NADH) from Link Reaction +2 reduced NAD (NADH) from glycolysis -> 10 reduced NAD (NADH). Each molecule of glucose yields 2 reduced FAD (FADH) from Kreb Cycle. ATP generated from the ETC and oxidative phosphorylation are = (10 reduced NAD 3) + (2 reduced FAD x 2) 34 ATP

Question 30

Equation of Glycolysis

Answer 30

1 glucose + 2 NAD+ → 2 nett ATP + 2 reduced NAD (NADH) + 2 H2O + 2 Pyruvate

Question 31

Equation of Link Reaction

Answer 31

2 pyruvate + 2 NAD→ 2 reduced NAD (NADH)+ 2 Acetyl CoA + 2CO2

Question 32

Significance of Krebs Cycle

Answer 32

1) The provision of reducing power for Electron Transport Chain (ETC) in the form of reduced NAD (NADH) and reduced FAD (FADH2) - The cycle oxidises organic fuel derived from pyruvate, generating 1 ATP, 3 reduced NAD (NADH), and 1 reduced FAD (FADH2) per turn (1 glucose 2 turns) - The electrons donated by the NADH and FADH2 to Electron Transport Chain is involved in oxidative phosphorylation to make ATP. 2) an Interconversion Centre Carbohydrate intermediates can be converted to amino acid or fatty acids.