CH:2 Life Processes in living Organisms Part - 1 Class 10th Solutions | Life Processes in living Organisms Part - 1 SSC Class 10 Questions And Answers
Fill in the blank and explain the statement.
After complete oxidation of a glucose molecule, 38 ATP molecules are formed.
Solution 1: Scientific and Written Exam Answer
In cellular respiration, glucose undergoes oxidation to produce energy in the form of ATP.
The complete breakdown of glucose occurs in three stages:
- Glycolysis: Occurs in the cytoplasm and produces 2 ATP.
- Krebs Cycle: Takes place in the mitochondria and produces 2 ATP.
- Electron Transport Chain (ETC): Produces 34 ATP.
Total ATP yield:
$$ 2 + 2 + 34 = 38 \text{ ATP} $$This energy is essential for various metabolic activities.
Solution 2: Simple and Understandable Answer
When our body breaks down food (glucose) to get energy, it produces 38 ATP molecules. This happens in three steps:
- Step 1: Glucose is broken down and gives 2 ATP.
- Step 2: More energy is released, producing 2 ATP.
- Step 3: The final step gives 34 ATP.
Example: Just like a phone needs a battery to work, our body needs ATP for energy!
Fill in the blank.
At the end of glycolysis, 2 pyruvate molecules are obtained.
Solution 1: Scientific and Written Exam Answer
Glycolysis is the first step in cellular respiration that occurs in the cytoplasm. It breaks down one glucose molecule (C₆H₁₂O₆) into two pyruvate (C₃H₄O₃) molecules, producing 2 ATP and 2 NADH.
Reaction:
$$ C_6H_{12}O_6 → 2C_3H_4O_3 + 2ATP + 2NADH $$This pyruvate enters the mitochondria for further energy production.
Solution 2: Simple and Understandable Answer
Glycolysis is like breaking a chocolate bar into two pieces. Here, 1 glucose is broken into 2 pyruvate.
- Step 1: Glucose is split into smaller parts.
- Step 2: It gives 2 ATP energy.
- Step 3: The two parts become pyruvate, which goes into the next step for more energy.
Example: Think of glycolysis like cutting a pizza into two equal slices!
Fill in the blank.
Genetic recombination occurs in pachytene phase of prophase of meiosis-I.
Solution 1: Scientific and Written Exam Answer
During meiosis-I, homologous chromosomes pair and exchange genetic material. This occurs in the pachytene phase of prophase-I through a process called crossing over.
Importance:
- Creates genetic variation.
- Ensures unique traits in offspring.
Example: Like shuffling a deck of cards, crossing over mixes genes!
Solution 2: Simple and Understandable Answer
When cells divide to form gametes (sperm or egg), genes from parents mix in the pachytene phase. This is why siblings look different!
Example: Like mixing two different paint colors to create a new shade.
Fill in the blank.
All chromosomes are arranged parallel to the equatorial plane of the cell in metaphase of mitosis.
Fill in the blank.
For formation of plasma membrane, phospholipid molecules are necessary.
Fill in the blank.
Our muscle cells perform anaerobic type of respiration during exercise.
Solution 1: Scientific and Written Exam Answer
During intense exercise, oxygen supply is low, so muscle cells switch to anaerobic respiration, producing lactic acid instead of using oxygen.
Reaction:
$$ C_6H_{12}O_6 → 2C_3H_6O_3 + 2ATP $$This causes muscle fatigue and cramps.
Solution 2: Simple and Understandable Answer
When we run fast, our body can't get enough oxygen, so muscles work without oxygen, producing lactic acid. This makes our legs feel tired.
Example: Running too fast feels like burning in your muscles due to lactic acid!
Write the definition.
Nutrition:
Scientific Definition: Nutrition is the process of intake, digestion, absorption, and utilization of food substances by an organism for growth, energy, and maintenance of life.
Simple Definition: Nutrition is how living beings eat food and use it for energy and growth.
Write the definition.
Nutrients:
Scientific Definition: Nutrients are essential substances obtained from food that provide energy, support growth, and help in body functions. Examples include carbohydrates, proteins, fats, vitamins, and minerals.
Simple Definition: Nutrients are important parts of food that help us stay healthy and strong.
Write the definition.
Proteins:
Scientific Definition: Proteins are large biomolecules made of amino acids that play a crucial role in building and repairing body tissues, producing enzymes, and supporting metabolic processes.
Simple Definition: Proteins are nutrients that help build muscles, repair wounds, and keep our body strong.
Write the definition.
Cellular Respiration:
Scientific Definition: Cellular respiration is a biochemical process in which cells break down glucose in the presence or absence of oxygen to produce energy in the form of ATP.
Simple Definition: Cellular respiration is how cells use food to make energy.
Write the definition.
Aerobic Respiration:
Scientific Definition: Aerobic respiration is the process of breaking down glucose using oxygen to release energy in the form of ATP, with carbon dioxide and water as byproducts.
Equation:
$$ C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + 38ATP $$Simple Definition: Aerobic respiration is when our body uses oxygen to turn food into energy.
Write the definition.
Glycolysis:
Scientific Definition: Glycolysis is the first step in cellular respiration, where one glucose molecule is broken down into two pyruvate molecules, producing ATP and NADH.
Equation:
$$ C_6H_{12}O_6 → 2C_3H_4O_3 + 2ATP + 2NADH $$Simple Definition: Glycolysis is the process of breaking sugar into smaller parts to make energy.
Distinguish between Glycolysis and TCA Cycle
Glycolysis | TCA Cycle (Krebs Cycle) |
---|---|
Occurs in the cytoplasm of the cell. | Occurs in the mitochondria. |
It is an anaerobic process (does not require oxygen). | It is an aerobic process (requires oxygen). |
Breaks down one glucose molecule (C₆H₁₂O₆) into two pyruvate molecules. | Further oxidizes pyruvate to release CO₂, H₂O, and energy. |
Produces a net gain of 2 ATP molecules per glucose. | Generates 2 ATP molecules per cycle but also produces NADH and FADH₂ for more ATP production. |
End products: Pyruvate, ATP, and NADH. | End products: CO₂, ATP, NADH, and FADH₂. |
Occurs in both aerobic and anaerobic respiration. | Occurs only in aerobic respiration. |
Summary:
- Glycolysis is the first step of cellular respiration and does not require oxygen.
- The TCA cycle is the second stage of aerobic respiration, releasing more energy.
- NADH and FADH₂ produced in the TCA cycle help in ATP synthesis via the electron transport chain.
Distinguish between Mitosis and Meiosis
Mitosis | Meiosis |
---|---|
Occurs in somatic (body) cells. | Occurs in reproductive cells (gametes: sperm & egg). |
Produces two daughter cells. | Produces four daughter cells. |
Daughter cells are diploid (2n), identical to the parent cell. | Daughter cells are haploid (n) and genetically different from the parent cell. |
Consists of one cell division. | Consists of two cell divisions (Meiosis I and Meiosis II). |
Maintains the chromosome number of the parent cell. | Reduces the chromosome number by half. |
Used for growth, repair, and asexual reproduction. | Used for sexual reproduction and genetic variation. |
Summary:
- Mitosis produces genetically identical cells for growth and repair.
- Meiosis produces genetically diverse gametes for reproduction.
- Meiosis introduces genetic variation through recombination and independent assortment.
Distinguish between Aerobic and Anaerobic Respiration
Aerobic Respiration | Anaerobic Respiration |
---|---|
Occurs in the presence of oxygen. | Occurs in the absence of oxygen. |
Complete breakdown of glucose takes place. | Incomplete breakdown of glucose occurs. |
End products are carbon dioxide (CO₂) and water (H₂O). | End products can be ethanol, lactic acid, and CO₂ (depending on the organism). |
Releases a large amount of energy (about 38 ATP per glucose molecule). | Releases less energy (about 2 ATP per glucose molecule). |
Occurs in most plants and animals, including humans. | Occurs in some microorganisms like yeast and certain muscle cells during heavy exercise. |
Example: Cellular respiration in humans. | Example: Fermentation in yeast and muscle cells during strenuous activity. |
Summary:
- Aerobic respiration uses oxygen and produces more energy.
- Anaerobic respiration occurs without oxygen and generates less energy.
- Anaerobic respiration is useful in situations where oxygen supply is limited.
Give scientific reason: Oxygen is necessary for complete oxidation of glucose.
Solution 1: Scientific and Written Exam Answer
Oxygen plays a crucial role in aerobic respiration, where glucose undergoes complete oxidation to produce energy. The reaction follows:
$$ C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + 38 ATP $$
Here, oxygen acts as the final electron acceptor in the electron transport chain (ETC), ensuring complete breakdown of glucose into carbon dioxide and water. This results in maximum ATP production, providing energy for various cellular activities.
Solution 2: Simple and Understandable Answer
Oxygen is important because it helps break down glucose completely into energy. When oxygen is available, the body can generate 38 ATP (energy units), which keeps us active. Without oxygen, only 2 ATP are produced, which is much less. That’s why oxygen is essential for proper energy production.
Give scientific reason: Fibers are one of the important nutrients.
Solution:
Fibers are essential nutrients that support proper digestion and overall health. They are mainly found in plant-based foods like fruits, vegetables, and whole grains. The importance of fibers includes:
- Improves Digestion: Fibers help in regulating bowel movements and preventing constipation.
- Controls Blood Sugar: Soluble fibers slow down glucose absorption, preventing sudden spikes in blood sugar levels.
- Reduces Cholesterol: Dietary fibers bind with bile acids, reducing bad cholesterol (LDL) levels.
- Aids in Weight Management: Fibers provide a feeling of fullness, reducing excessive food intake.
- Promotes Gut Health: They act as food for beneficial gut bacteria, supporting a healthy digestive system.
Thus, including fiber-rich foods in our daily diet helps maintain overall health and well-being.
Give scientific reason: Cell division is one of the very important properties of cells and living organisms.
Solution:
Cell division is an essential biological process that plays a crucial role in growth, repair, and reproduction. It ensures the continuity of life by forming new cells. The importance of cell division includes:
- Growth and Development: In multicellular organisms, cell division increases the number of cells, leading to growth and development.
- Tissue Repair and Healing: It helps in replacing damaged or dead cells, allowing wound healing and tissue regeneration.
- Asexual and Sexual Reproduction: In unicellular organisms, cell division leads to reproduction, while in multicellular organisms, it plays a role in gamete formation.
- Genetic Continuity: It ensures that genetic material is accurately passed from one generation to the next.
- Maintenance of Cell Size: Cell division prevents cells from growing too large, maintaining an optimal surface-area-to-volume ratio for efficient functioning.
Thus, cell division is a fundamental process necessary for survival, growth, and reproduction in living organisms.
Give scientific reason: Sometimes, higher plants and animals too perform anaerobic respiration.
Solution:
Although aerobic respiration is the primary mode of energy production in higher plants and animals, they may perform anaerobic respiration under certain conditions:
- Oxygen Deficiency: In the absence of sufficient oxygen, cells switch to anaerobic respiration to produce energy.
- Muscle Fatigue in Animals: During intense physical activities like running or weightlifting, oxygen supply may be insufficient, leading to anaerobic respiration in muscle cells. This produces lactic acid, causing muscle fatigue.
- Waterlogged Conditions in Plants: Roots of plants in flooded or waterlogged soil experience low oxygen levels and switch to anaerobic respiration.
- Fermentation Process: Certain plant cells, such as in fruits undergoing fermentation, rely on anaerobic respiration to produce energy in low-oxygen conditions.
Thus, under oxygen-deficient conditions, both higher plants and animals temporarily perform anaerobic respiration for survival.
Give scientific reason: Kreb's cycle is also known as Citric Acid Cycle.
Solution:
The Kreb’s cycle is called the Citric Acid Cycle because citric acid is the first stable intermediate compound formed in this cycle. The reasons are as follows:
- First Compound Formed: The cycle begins with the condensation of Acetyl-CoA with Oxaloacetic Acid (OAA) to form Citric Acid (C₆H₈O₇).
- Central Role in Cellular Respiration: It is a crucial part of aerobic respiration, occurring in the mitochondria and generating ATP, NADH, and FADH₂.
- Named by Hans Krebs: The cycle was discovered by Sir Hans Krebs in 1937, and he initially named it after citric acid.
- Continuous Regeneration of Citric Acid: Since citric acid is continuously formed and broken down in the cycle, it is an important characteristic of the process.
Thus, due to the formation and significance of citric acid, the Krebs cycle is also referred to as the Citric Acid Cycle (CAC).
Explain the Glycolysis in Detail.
Solution:
What is Glycolysis?
Glycolysis is the first step of cellular respiration, where one molecule of glucose (C₆H₁₂O₆) is broken down into two molecules of pyruvate (C₃H₄O₃) in the cytoplasm of the cell. It is an anaerobic process, meaning it does not require oxygen.
Steps of Glycolysis:
The process of glycolysis occurs in 10 enzyme-catalyzed steps, which can be divided into two main phases:
1. Preparatory Phase (Energy Investment Phase)
- Step 1: Glucose is phosphorylated using ATP to form Glucose-6-phosphate.
- Step 2: Glucose-6-phosphate is converted into Fructose-6-phosphate.
- Step 3: Another ATP is used to convert Fructose-6-phosphate into Fructose-1,6-bisphosphate.
- Step 4: Fructose-1,6-bisphosphate is split into two molecules: Glyceraldehyde-3-phosphate (G3P) and Dihydroxyacetone phosphate (DHAP).
- Step 5: DHAP is converted into G3P, so now there are two G3P molecules.
2. Payoff Phase (Energy Harvesting Phase)
- Step 6: G3P is oxidized and NAD⁺ is reduced to NADH.
- Step 7: ATP is generated by substrate-level phosphorylation.
- Step 8: 3-Phosphoglycerate is converted into 2-Phosphoglycerate.
- Step 9: Water is removed to form Phosphoenolpyruvate (PEP).
- Step 10: PEP is converted into Pyruvate, producing another ATP.
End Products of Glycolysis:
- 2 Pyruvate molecules
- 2 ATP (Net Gain)
- 2 NADH
- 2 H₂O
Importance of Glycolysis:
- Provides energy (ATP) for cellular activities.
- Occurs in all living organisms, from bacteria to humans.
- Serves as the starting point for both aerobic and anaerobic respiration.
With the help of suitable diagrams, explain mitosis in detail.
Solution 1: Scientific and Written Exam Answer
Mitosis is a type of cell division in which a single parent cell divides into two identical daughter cells. This process ensures that each daughter cell receives an exact copy of the parent cell’s genetic material.
Phases of Mitosis:
1. Prophase: Chromatin condenses into chromosomes, and the nuclear membrane starts to disintegrate. The centrioles move to opposite poles, forming spindle fibers.
2. Metaphase: Chromosomes align at the cell’s equatorial plane, attached to spindle fibers at their centromeres.
3. Anaphase: Sister chromatids separate and move toward opposite poles as spindle fibers contract.
4. Telophase: The nuclear membrane reappears around each set of chromosomes, forming two distinct nuclei. The cell begins cytokinesis, leading to the formation of two daughter cells.
Formula for chromosome number:
$$ 2n \to 2n + 2n $$
Mitosis ensures genetic stability, essential for growth, repair, and asexual reproduction.
Solution 2: Simple and Understandable Answer
Mitosis is a process where one cell divides into two identical cells. This helps in growth and repair in our body.
Steps of Mitosis:
1. Prophase: The cell prepares to divide. The genetic material condenses, and the nucleus starts to break down.
2. Metaphase: Chromosomes line up in the center of the cell.
3. Anaphase: The chromosomes split and move to opposite sides.
4. Telophase: Two new nuclei form, and the cell is ready to split into two.
Example: If you get a cut on your skin, mitosis helps create new skin cells to heal the wound.
Mitosis is important for growing, healing, and replacing old cells in our body.
With the help of suitable diagrams, explain the five stages of prophase-I of meiosis.
Solution 1: Scientific and Written Exam Answer
Prophase-I is the longest and most complex stage of meiosis-I. It consists of five sub-stages: Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis. This phase is crucial for genetic recombination.
1. Leptotene: The chromatin condenses into thread-like chromosomes, and homologous chromosomes start aligning.
2. Zygotene: Homologous chromosomes pair up to form bivalents (synapsis), and a protein complex called the synaptonemal complex forms between them.
3. Pachytene: Crossing-over occurs at chiasmata, where genetic material is exchanged between homologous chromosomes, increasing genetic variation.
4. Diplotene: The synaptonemal complex dissolves, and homologous chromosomes begin to separate, but remain connected at chiasmata.
5. Diakinesis: The chromosomes further condense, the nuclear membrane disintegrates, and spindle fibers start forming, marking the end of prophase-I.
Formula for chromosome number:
$$ 2n \to n + n $$
This phase ensures genetic diversity through crossing-over, which is essential for evolution.
Solution 2: Simple and Understandable Answer
Prophase-I is the first and most important stage of meiosis-I. It has five steps where the genetic material is prepared for division.
1. Leptotene: Chromosomes become visible like thin threads.
2. Zygotene: Matching chromosome pairs come together.
3. Pachytene: Chromosomes swap small sections of DNA (crossing-over), which makes every cell unique.
4. Diplotene: The paired chromosomes start to separate but stay connected at some points.
5. Diakinesis: The chromosomes are fully prepared for division as the nuclear membrane disappears.
Example: This process ensures that siblings from the same parents look different from each other.
Diagram of Prophase-I:
Prophase-I is important because it helps in genetic variation, which is why no two people (except identical twins) are exactly alike.
How all the life processes contribute to the growth and development of the body?
Solution 1: Scientific and Written Exam Answer
Growth and development in living organisms are the result of various essential life processes. These biological functions work together to maintain homeostasis and sustain life.
1. Nutrition: The process of obtaining and utilizing food provides essential nutrients and energy for growth, repair, and maintenance of body tissues.
2. Respiration: The breakdown of glucose during cellular respiration releases ATP (Adenosine Triphosphate), which provides energy for metabolic activities.
3. Circulation: The transport of oxygen, nutrients, hormones, and waste materials through blood ensures the proper functioning of all body systems.
4. Excretion: The removal of metabolic waste (e.g., urea, CO₂) maintains internal balance and prevents toxicity.
5. Reproduction: Though not directly related to individual growth, it ensures the continuity of life.
6. Nervous and Endocrine Control: The nervous system and hormones regulate growth and coordinate bodily functions.
Mathematical representation of energy production:
$$ C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + Energy (ATP) $$
Conclusion: All life processes work together to enable proper growth and development by ensuring a steady supply of nutrients, energy, and waste removal.
Solution 2: Simple and Understandable Answer
Our body grows and develops because of different life processes that keep us alive and healthy.
1. Eating (Nutrition): Food gives our body the energy and nutrients needed to grow.
2. Breathing (Respiration): Oxygen helps break down food into energy.
3. Blood Circulation: Blood carries food, oxygen, and hormones to all body parts.
4. Removing Waste (Excretion): Our body gets rid of harmful substances through urine, sweat, and breath.
5. Thinking and Controlling (Nervous System): The brain and hormones guide our body on how to grow properly.
Example: When children eat a balanced diet, breathe properly, and get enough rest, their body grows taller and stronger.
All these life processes work together to make sure we grow in a healthy way!
Explain the Kreb's cycle with reaction.
Solution 1: Scientific and Written Exam Answer
The Kreb's cycle, also known as the Citric Acid Cycle (CAC) or Tricarboxylic Acid Cycle (TCA), is a crucial metabolic pathway that occurs in the mitochondrial matrix. It is the second stage of aerobic respiration and plays a significant role in energy production.
Steps of Kreb’s Cycle:
1. Formation of Citrate: Acetyl-CoA (2C) combines with Oxaloacetate (4C) to form Citrate (6C).
2. Isomerization: Citrate is converted into Isocitrate.
3. Oxidation and Decarboxylation: Isocitrate is oxidized to α-Ketoglutarate (5C), releasing CO₂ and NADH.
4. Second Decarboxylation: α-Ketoglutarate is converted into Succinyl-CoA (4C), producing another CO₂ and NADH.
5. ATP Formation: Succinyl-CoA is converted into Succinate, producing ATP (or GTP).
6. Regeneration of Oxaloacetate: Succinate undergoes oxidation steps, forming Fumarate, Malate, and finally regenerating Oxaloacetate.
Overall Reaction of Kreb's Cycle:
$$ Acetyl-CoA + 3NAD^+ + FAD + ADP + P_i + 2H_2O → 2CO_2 + 3NADH + 3H^+ + FADH_2 + ATP + CoA $$
End Products: Per cycle, it generates 3 NADH, 1 FADH₂, 1 ATP, and 2 CO₂.
Conclusion: The Kreb’s cycle is a vital process for energy production, as the high-energy molecules (NADH and FADH₂) further participate in the Electron Transport Chain (ETC) to generate ATP.
Solution 2: Simple and Understandable Answer
The Kreb’s cycle is an important process that happens in the mitochondria of our cells. It helps break down food and release energy in the form of ATP.
Simple Steps of Kreb’s Cycle:
1. Our body converts food into a special molecule called Acetyl-CoA.
2. Acetyl-CoA enters the Kreb’s cycle and combines with another molecule to form Citrate.
3. This citrate goes through several changes, releasing carbon dioxide (CO₂) and producing energy-rich molecules like NADH and FADH₂.
4. These molecules store energy, which is later used to produce ATP.
5. The cycle ends by making Oxaloacetate, which helps start the process again.
Example: The Kreb’s cycle works like a power plant that takes in fuel (food) and produces electricity (ATP) for the body to function.
It is one of the most important energy-producing processes that keeps us alive!
Redraw the flow-chart with corrections. Explain in brief the process of obtaining energy through oxidation of carbohydrates, lipids & proteins.
Solution 1: Scientific and Written Exam Answer
The process of obtaining energy in living organisms occurs through the oxidation of carbohydrates, lipids, and proteins. These macromolecules undergo biochemical pathways to generate ATP, which is the primary energy currency of the cell.
Corrected Flowchart:
Explanation of Each Term in the Flowchart:
- Glycolysis: This is the first step of cellular respiration where glucose is broken down into pyruvic acid in the cytoplasm.
- Pyruvic Acid: The three-carbon compound formed at the end of glycolysis. It acts as a key intermediate for further energy production.
- Acetyl Coenzyme A (Acetyl-CoA): Pyruvic acid is converted into Acetyl-CoA before entering the Krebs cycle. It is a crucial molecule that connects glycolysis and fat metabolism.
- Krebs Cycle: Also known as the citric acid cycle, it occurs in the mitochondria and produces NADH, FADH₂, and ATP by oxidizing Acetyl-CoA.
- Electron Transport Chain (ETC): This is the final stage of cellular respiration, where NADH and FADH₂ donate electrons to produce ATP.
- Lipids: These are broken down into fatty acids and glycerol. Fatty acids undergo β-oxidation to form Acetyl-CoA, which enters the Krebs cycle for ATP production.
- Amino Acids: The building blocks of proteins. They undergo deamination, where the amino group is removed, and the remaining carbon skeleton enters the Krebs cycle.
- Proteins: These are broken down into amino acids, which are used for energy production if carbohydrates and lipids are insufficient.
Oxidation Process of Carbohydrates, Lipids, and Proteins:
1. Oxidation of Carbohydrates:
Carbohydrates like glucose undergo glycolysis, where glucose (C₆H₁₂O₆) is converted into pyruvic acid. Pyruvic acid then enters the Krebs cycle via Acetyl-CoA, producing NADH and FADH₂. These molecules participate in the Electron Transport Chain (ETC) to generate ATP.
Overall Reaction:
$$ C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + 36ATP $$
2. Oxidation of Lipids (Fats):
Lipids are broken down into glycerol and fatty acids. Fatty acids undergo β-oxidation to form Acetyl-CoA, which enters the Krebs cycle. This process produces a large amount of ATP.
3. Oxidation of Proteins:
Proteins are broken down into amino acids, which undergo deamination to remove the amino group. The remaining carbon skeletons are converted into intermediates of the Krebs cycle, which are further oxidized to generate ATP.
Conclusion:
Oxidation of carbohydrates, lipids, and proteins provides ATP, which is used for various biological functions. Lipids yield the highest energy per gram, followed by carbohydrates and proteins.
Solution 2: Simple and Understandable Answer
Our body gets energy from three main food sources: carbohydrates, fats (lipids), and proteins. These are broken down in different ways to produce ATP, which is the energy our cells use.
1. Carbohydrates: Carbs (like rice and bread) are converted into glucose. Glucose undergoes glycolysis and enters the Krebs cycle to produce energy.
2. Lipids (Fats): Fats break down into fatty acids, which are converted into Acetyl-CoA. This then enters the Krebs cycle, producing even more energy than carbohydrates.
3. Proteins: Proteins break down into amino acids. After removing the amino group, they enter the Krebs cycle to produce energy.
Example: If you eat rice (carbohydrates), butter (fat), and eggs (protein), all of them provide energy, but fats give the most ATP!