Metabolism and Energy Regulation Study Guide – Anatomy & Physiology

Q1. Within a living cell, the oxidation of one molecule is always coupled with the simultaneous _________ of another molecule.

Background

Topic: Redox Reactions in Cellular Metabolism

This question tests your understanding of how oxidation and reduction reactions are paired in biological systems, especially during energy transfer processes.

Key Terms:

• Oxidation: Loss of electrons from a molecule.

• Reduction: Gain of electrons by a molecule.

• Redox Reaction: A chemical reaction involving both reduction and oxidation.

Step-by-Step Guidance

1. Recall that in metabolism, electrons are transferred between molecules.

2. When one molecule loses electrons (is oxidized), another must gain those electrons (is reduced).

3. Think about the electron carriers (like NAD+ and FAD) and how they participate in these reactions.

4. Fill in the blank with the process that is paired with oxidation.

Try solving on your own before revealing the answer!

Final Answer: Reduction

Oxidation is always coupled with reduction; electrons lost by one molecule are gained by another.

Q2. In the transitional step between glycolysis and the Krebs cycle _____________________ occurs.

Background

Topic: Cellular Respiration – Glycolysis to Krebs Cycle

This question is about the process that connects glycolysis to the Krebs cycle, preparing pyruvate for entry into the mitochondria.

Key Terms:

• Glycolysis: Breakdown of glucose into pyruvate.

• Krebs Cycle: Also called the citric acid cycle; occurs in mitochondria.

• Transitional Step: The conversion of pyruvate to a molecule that enters the Krebs cycle.

Step-by-Step Guidance

1. Recall what happens to pyruvate after glycolysis.

2. Think about the enzyme complex involved in this step.

3. Consider what molecule is produced and what is released (e.g., CO2).

4. Identify the process that prepares pyruvate for the Krebs cycle.

Try solving on your own before revealing the answer!

Final Answer: Pyruvate is converted to Acetyl-CoA (pyruvate decarboxylation)

Pyruvate undergoes decarboxylation and is converted to Acetyl-CoA, releasing CO2 and producing NADH.

Q3. Essential amino acids are those that ______________________

Background

Topic: Nutrition – Amino Acids

This question tests your knowledge of amino acids and their classification based on dietary requirements.

Key Terms:

• Essential Amino Acids: Amino acids that cannot be synthesized by the body.

• Non-essential Amino Acids: Amino acids that can be synthesized by the body.

Step-by-Step Guidance

1. Recall the definition of essential nutrients.

2. Think about whether the body can make these amino acids or must obtain them from the diet.

3. Fill in the blank with the correct description.

Try solving on your own before revealing the answer!

Final Answer: Must be obtained from the diet because the body cannot synthesize them

Essential amino acids are required in the diet since the body cannot produce them.

Q4. In fatty acid metabolism, which molecule enters the Krebs cycle? ___________________

Background

Topic: Lipid Metabolism

This question is about the breakdown of fatty acids and the molecule that links this process to the Krebs cycle.

Key Terms:

• Beta-oxidation: The process of breaking down fatty acids.

• Krebs Cycle: Central metabolic pathway for energy production.

• Acetyl-CoA: The molecule that enters the Krebs cycle.

Step-by-Step Guidance

1. Recall the steps of fatty acid breakdown (beta-oxidation).

2. Identify the end product of beta-oxidation.

3. Determine which molecule is used in the Krebs cycle.

Try solving on your own before revealing the answer!

Final Answer: Acetyl-CoA

Acetyl-CoA is produced from fatty acids and enters the Krebs cycle for further energy production.

Q5. A nutrient: (define) _________________________________

Background

Topic: Nutrition – Nutrient Definition

This question asks for the definition of a nutrient, a fundamental concept in physiology and nutrition.

Key Terms:

• Nutrient: A substance required for growth, maintenance, and normal functioning.

Step-by-Step Guidance

1. Think about what substances are considered nutrients (carbohydrates, proteins, fats, vitamins, minerals, water).

2. Consider their role in the body (energy, structure, regulation).

3. Formulate a concise definition.

Try solving on your own before revealing the answer!

Final Answer: A substance that provides nourishment essential for growth and the maintenance of life

Nutrients are required for energy, building tissues, and regulating bodily functions.

Q6. Which hormone stimulates Gluconeogenesis? __________________

Background

Topic: Hormonal Regulation of Metabolism

This question tests your knowledge of hormones involved in glucose production from non-carbohydrate sources.

Key Terms:

• Gluconeogenesis: Formation of glucose from non-carbohydrate sources.

• Hormones: Chemical messengers that regulate metabolic pathways.

Step-by-Step Guidance

1. Recall which hormones are released during fasting or stress.

2. Think about hormones that increase blood glucose levels.

3. Identify the hormone that stimulates gluconeogenesis in the liver.

Try solving on your own before revealing the answer!

Final Answer: Glucagon (and cortisol)

Glucagon is the primary hormone stimulating gluconeogenesis; cortisol also plays a role.

Q7. The electron transport chain is a stepwise release of energy for the generation of ___________________.

Background

Topic: Cellular Respiration – Electron Transport Chain

This question is about the main purpose of the electron transport chain in cellular metabolism.

Key Terms:

• Electron Transport Chain (ETC): Series of protein complexes in mitochondria.

• ATP: Adenosine triphosphate, the cell's energy currency.

Step-by-Step Guidance

1. Recall what happens to electrons from NADH and FADH2 in the ETC.

2. Think about how energy is used to pump protons and create a gradient.

3. Identify the molecule synthesized as a result of this energy release.

Try solving on your own before revealing the answer!

Final Answer: ATP

The electron transport chain generates ATP through oxidative phosphorylation.

Q8. Body temperature is ultimately regulated by the _____________.

Background

Topic: Thermoregulation

This question tests your knowledge of the organ responsible for controlling body temperature.

Key Terms:

• Hypothalamus: Brain region regulating homeostasis.

• Thermoregulation: Maintenance of internal body temperature.

Step-by-Step Guidance

1. Recall which part of the brain is involved in homeostatic regulation.

2. Think about the "thermostat" of the body.

3. Fill in the blank with the correct anatomical structure.

Try solving on your own before revealing the answer!

Final Answer: Hypothalamus

The hypothalamus is the main regulator of body temperature.

Q9. The energy for metabolism is primarily transferred by molecules for the purpose of ____________________.

Background

Topic: Energy Transfer in Metabolism

This question is about the role of energy-carrying molecules in cellular processes.

Key Terms:

• ATP: Main energy carrier in cells.

• Metabolism: All chemical reactions in the body.

Step-by-Step Guidance

1. Recall what ATP is used for in cells.

2. Think about cellular functions that require energy.

3. Fill in the blank with the main purpose of energy transfer.

Try solving on your own before revealing the answer!

Final Answer: Cellular work (such as synthesis, movement, and transport)

Energy is transferred for cellular functions like biosynthesis, muscle contraction, and active transport.

Q10. Which of the following are minerals that function as coenzymes? _________________

Background

Topic: Vitamins and Minerals in Metabolism

This question tests your knowledge of minerals that act as cofactors or coenzymes in metabolic reactions.

Key Terms:

• Coenzyme: Non-protein compound assisting enzyme function.

• Minerals: Inorganic elements required for metabolism.

Step-by-Step Guidance

1. Recall which minerals are commonly involved in enzyme activity.

2. Think about examples like magnesium, zinc, and iron.

3. Fill in the blank with appropriate minerals.

Try solving on your own before revealing the answer!

Final Answer: Magnesium, zinc, iron, copper, selenium

These minerals act as cofactors for various enzymes in metabolic pathways.

Q11. The function of HDL’s is to : __________________________________________

Background

Topic: Lipoproteins and Cholesterol Transport

This question is about the role of high-density lipoproteins (HDL) in the body.

Key Terms:

• HDL: High-density lipoprotein, "good" cholesterol.

• Cholesterol Transport: Movement of cholesterol in the blood.

Step-by-Step Guidance

1. Recall the difference between HDL and LDL.

2. Think about the direction of cholesterol transport (to or from tissues).

3. Fill in the blank with the main function of HDL.

Try solving on your own before revealing the answer!

Final Answer: Transport cholesterol from tissues to the liver for excretion

HDL removes excess cholesterol from cells and carries it to the liver for disposal.

Q12. Vit. D deficiency causes: _____________________________

Background

Topic: Vitamins and Health

This question tests your knowledge of the consequences of vitamin D deficiency.

Key Terms:

• Vitamin D: Essential for calcium absorption and bone health.

• Deficiency: Lack of sufficient vitamin D.

Step-by-Step Guidance

1. Recall the role of vitamin D in the body.

2. Think about diseases associated with poor bone mineralization.

3. Fill in the blank with the main consequence.

Try solving on your own before revealing the answer!

Final Answer: Rickets (in children) and osteomalacia (in adults)

Vitamin D deficiency leads to soft, weak bones due to impaired calcium absorption.

Q13. Each gram of fat yields about _____ kcal.

Background

Topic: Energy Content of Nutrients

This question is about the caloric value of macronutrients, specifically fat.

Key Terms:

• Calorie (kcal): Unit of energy.

• Fat: High-energy macronutrient.

Step-by-Step Guidance

1. Recall the energy values for carbohydrates, proteins, and fats.

2. Compare the kcal per gram for each macronutrient.

3. Fill in the blank with the value for fat.

Try solving on your own before revealing the answer!

Final Answer: 9 kcal

Each gram of fat provides about 9 kilocalories of energy.

Q14. The hunger and satiety centers for the regulation of food intake are located in the ________________.

Background

Topic: Regulation of Food Intake

This question is about the brain region responsible for controlling hunger and fullness.

Key Terms:

• Satiety Center: Controls feeling of fullness.

• Hunger Center: Controls feeling of hunger.

• Hypothalamus: Brain region involved in regulation.

Step-by-Step Guidance

1. Recall which part of the brain regulates homeostasis.

2. Think about the centers for hunger and satiety.

3. Fill in the blank with the correct anatomical location.

Try solving on your own before revealing the answer!

Final Answer: Hypothalamus

The hypothalamus contains the centers for hunger and satiety.

Q15. An example of anabolism is the ________________________________.

Background

Topic: Metabolic Pathways – Anabolism

This question tests your understanding of anabolic processes, which build up molecules in the body.

Key Terms:

• Anabolism: Building larger molecules from smaller ones.

• Catabolism: Breaking down molecules for energy.

Step-by-Step Guidance

1. Recall examples of biosynthetic processes.

2. Think about processes like protein synthesis, glycogen formation, or DNA replication.

3. Fill in the blank with a specific example.

Try solving on your own before revealing the answer!

Final Answer: Protein synthesis (or glycogen synthesis)

Anabolism includes processes like building proteins from amino acids.

Q16. The amount of energy from food transferred to ATP and available for cellular functions equals about ______%

Background

Topic: Energy Efficiency in Metabolism

This question is about how much energy from food is actually converted to usable ATP.

Key Terms:

• ATP: Usable energy for cells.

• Energy Efficiency: Percentage of energy transferred.

Step-by-Step Guidance

1. Recall that not all energy from food is converted to ATP; some is lost as heat.

2. Think about the typical efficiency of cellular respiration.

3. Fill in the blank with the approximate percentage.

Try solving on your own before revealing the answer!

Final Answer: 40%

About 40% of energy from food is transferred to ATP; the rest is lost as heat.

Q17. The major regulator of BMR is _______________.

Background

Topic: Basal Metabolic Rate Regulation

This question is about the hormone that most strongly influences basal metabolic rate.

Key Terms:

• BMR: Basal metabolic rate.

• Thyroid Hormones: Regulate metabolism.

Step-by-Step Guidance

1. Recall which hormones increase metabolic activity.

2. Think about the role of thyroxine (T4) and triiodothyronine (T3).

3. Fill in the blank with the main regulator.

Try solving on your own before revealing the answer!

Final Answer: Thyroid hormones (especially thyroxine/T4)

Thyroid hormones are the primary regulators of BMR.

Q18. Too high a core body temperature can be fatal because it causes __________________.

Background

Topic: Effects of Hyperthermia

This question is about the dangers of elevated body temperature.

Key Terms:

• Hyperthermia: Excessively high body temperature.

• Protein Denaturation: Loss of protein structure and function.

Step-by-Step Guidance

1. Recall what happens to enzymes and proteins at high temperatures.

2. Think about the consequences for cellular function.

3. Fill in the blank with the main effect.

Try solving on your own before revealing the answer!

Final Answer: Protein denaturation (and organ failure)

High temperatures cause proteins to lose their structure, leading to cell and organ dysfunction.

Q19. In a negative feedback mechanism of body temperature regulation, in response to a decrease of body temperature, the hypothalamus releases _________________.

Background

Topic: Thermoregulation – Negative Feedback

This question is about the body's response to cold and the hypothalamic signals involved.

Key Terms:

• Negative Feedback: Mechanism to restore homeostasis.

• Hypothalamus: Regulates temperature.

• Thyrotropin-releasing hormone (TRH): Stimulates thyroid activity.

Step-by-Step Guidance

1. Recall what happens when body temperature drops.

2. Think about hormones released to increase metabolic rate and heat production.

3. Fill in the blank with the hormone released by the hypothalamus.

Try solving on your own before revealing the answer!

Final Answer: Thyrotropin-releasing hormone (TRH)

TRH stimulates the pituitary to release TSH, increasing thyroid hormone production and heat generation.

Q20. When you touch a cool object, you lose heat by ______________.

Background

Topic: Heat Transfer Mechanisms

This question is about the process by which heat is transferred from the body to a cooler object.

Key Terms:

• Conduction: Direct transfer of heat through contact.

• Radiation, convection, evaporation: Other heat loss mechanisms.

Step-by-Step Guidance

1. Recall the four main ways the body loses heat.

2. Think about which mechanism involves direct contact.

3. Fill in the blank with the correct term.

Try solving on your own before revealing the answer!

Final Answer: Conduction

Heat is lost by conduction when touching a cooler object.

Q21. When, as a result of pyrogens, the body thermostat is set to a higher temperature, you will experience __________.

Background

Topic: Fever and Pyrogens

This question is about the physiological response to fever-inducing substances.

Key Terms:

• Pyrogens: Substances that cause fever.

• Chills: Sensation of cold during fever onset.

Step-by-Step Guidance

1. Recall what happens when the hypothalamus increases the set point for body temperature.

2. Think about the body's response to this new set point.

3. Fill in the blank with the typical symptom experienced.

Try solving on your own before revealing the answer!

Final Answer: Chills (shivering)

When the set point rises, you feel cold and shiver to generate heat.

Q22. A coupled chemical reaction that directly transfers a high energy phosphate group from a substrate to ADP, producing ATP is called ______________________________.

Background

Topic: ATP Formation – Substrate-Level Phosphorylation

This question is about the mechanism of ATP production during glycolysis and the Krebs cycle.

Key Terms:

• Substrate-level phosphorylation: Direct transfer of phosphate to ADP.

• Oxidative phosphorylation: ATP production via electron transport chain.

Step-by-Step Guidance

1. Recall the two main ways ATP is produced in cells.

2. Think about which process involves direct transfer from a substrate.

3. Fill in the blank with the correct term.

Try solving on your own before revealing the answer!

Final Answer: Substrate-level phosphorylation

ATP is produced by direct transfer of a phosphate group from a substrate to ADP.

Q23. As a result of glycolysis, there is a net gain of _______ ATP molecules?

Background

Topic: Glycolysis – ATP Yield

This question is about the net ATP produced during glycolysis.

Key Terms:

• Glycolysis: Breakdown of glucose to pyruvate.

• ATP: Energy currency.

Step-by-Step Guidance

1. Recall the total ATP produced and used during glycolysis.

2. Subtract the ATP used from the ATP produced.

3. Fill in the blank with the net gain.

Try solving on your own before revealing the answer!

Final Answer: 2 ATP

Glycolysis produces 4 ATP but uses 2, resulting in a net gain of 2 ATP.

Q24. For every glucose molecule metabolized, how many CO2 molecules are produced?

Background

Topic: Cellular Respiration – CO2 Production

This question is about the total carbon dioxide produced from complete oxidation of glucose.

Key Terms:

• Glucose: C6H12O6

• CO2: Carbon dioxide, waste product.

Step-by-Step Guidance

1. Recall the steps of cellular respiration: glycolysis, transitional step, Krebs cycle.

2. Count the CO2 produced in each step.

3. Sum the total CO2 molecules produced per glucose.

Try solving on your own before revealing the answer!

Final Answer: 6 CO2

Complete oxidation of one glucose molecule produces 6 CO2 molecules.

Q25. In which cellular component does glycolysis occur? ______________

Background

Topic: Cellular Respiration – Glycolysis Location

This question is about the site of glycolysis within the cell.

Key Terms:

• Cytoplasm: Fluid part of the cell outside organelles.

• Mitochondria: Site of Krebs cycle and ETC.

Step-by-Step Guidance

1. Recall where glycolysis takes place compared to other steps of cellular respiration.

2. Fill in the blank with the correct cellular location.

Try solving on your own before revealing the answer!

Final Answer: Cytoplasm

Glycolysis occurs in the cytoplasm of the cell.

Q26. The majority of fat in the body is stored in fat cells located ________________

Background

Topic: Fat Storage in the Body

This question is about the location of adipose tissue in the body.

Key Terms:

• Adipocytes: Fat cells.

• Adipose Tissue: Tissue specialized for fat storage.

Step-by-Step Guidance

1. Recall the main sites of fat storage.

2. Think about subcutaneous and visceral fat.

3. Fill in the blank with the main location.

Try solving on your own before revealing the answer!

Final Answer: Subcutaneous tissue (under the skin)

Most fat is stored in adipocytes in subcutaneous tissue.

Q27. Acetone, acetoacetic acid and beta-hydroxybutyric acid are: ______________.

Background

Topic: Ketone Bodies

This question is about the products of fatty acid metabolism during fasting or diabetes.

Key Terms:

• Ketone Bodies: Produced during fat metabolism.

• Acetone, acetoacetic acid, beta-hydroxybutyric acid: Types of ketone bodies.

Step-by-Step Guidance

1. Recall what happens during prolonged fasting or low carbohydrate intake.

2. Think about the molecules produced from acetyl-CoA.

3. Fill in the blank with the correct term.

Try solving on your own before revealing the answer!

Final Answer: Ketone bodies

These are the three main ketone bodies produced during fat metabolism.

Q28. An increase in urea in the blood would indicate an increase in the breakdown of ____________.

Background

Topic: Protein Metabolism – Urea Cycle

This question is about the relationship between protein breakdown and urea production.

Key Terms:

• Urea: Waste product from amino acid breakdown.

• Protein Catabolism: Breakdown of proteins.

Step-by-Step Guidance

1. Recall what happens to amino groups during protein breakdown.

2. Think about the urea cycle in the liver.

3. Fill in the blank with the correct macronutrient.

Try solving on your own before revealing the answer!

Final Answer: Proteins (amino acids)

Urea is produced from the breakdown of amino acids in proteins.

Q29. Before Amino acids can enter the Krebs cycle, they must undergo ____________.

Background

Topic: Amino Acid Metabolism

This question is about the process required to prepare amino acids for entry into the Krebs cycle.

Key Terms:

• Deamination: Removal of amino group.

• Krebs Cycle: Central metabolic pathway.

Step-by-Step Guidance

1. Recall what must be removed from amino acids before they can be used for energy.

2. Think about the fate of the amino group.

3. Fill in the blank with the correct process.

Try solving on your own before revealing the answer!

Final Answer: Deamination

Amino acids must be deaminated before entering the Krebs cycle.

Q30. What structure is formed immediately after glucose enters the cell? _______________

Background

Topic: Glucose Metabolism

This question is about the first step in cellular glucose metabolism.

Key Terms:

• Glucose-6-phosphate: First product after glucose enters cell.

• Phosphorylation: Addition of phosphate group.

Step-by-Step Guidance

1. Recall what happens to glucose upon entry into the cell.

2. Think about the enzyme involved (hexokinase).

3. Fill in the blank with the structure formed.

Try solving on your own before revealing the answer!

Final Answer: Glucose-6-phosphate

Glucose is phosphorylated to glucose-6-phosphate upon entering the cell.

Q31. Which structure will undergo different reactions, depending on whether oxygen is plentiful, or in short supply? ____________.

Background

Topic: Cellular Respiration – Aerobic vs Anaerobic

This question is about the molecule that has different metabolic fates based on oxygen availability.

Key Terms:

• Pyruvate: End product of glycolysis.

• Aerobic: With oxygen.

• Anaerobic: Without oxygen.

Step-by-Step Guidance

1. Recall the end product of glycolysis.

2. Think about what happens to this molecule in aerobic vs anaerobic conditions.

3. Fill in the blank with the correct structure.

Try solving on your own before revealing the answer!

Final Answer: Pyruvate

Pyruvate is converted to acetyl-CoA in aerobic conditions or to lactate in anaerobic conditions.

Q32. The main hormones that are active in the absorptive state are: __________ _________

Background

Topic: Hormonal Regulation – Absorptive State

This question is about the hormones that regulate metabolism after eating.

Key Terms:

• Absorptive State: Period after eating.

• Insulin: Promotes storage of nutrients.

• Other hormones: May include others like thyroid hormones.

Step-by-Step Guidance

1. Recall which hormones are released after a meal.

2. Think about hormones that promote glucose uptake and storage.

3. Fill in the blanks with the main hormones.

Try solving on your own before revealing the answer!

Final Answer: Insulin (and possibly thyroid hormones)

Insulin is the main hormone active in the absorptive state.

Q33. During the absorptive state, amino acids are used by most cells for ______________.

Background

Topic: Amino Acid Utilization – Absorptive State

This question is about the fate of amino acids after eating.

Key Terms:

• Protein Synthesis: Building proteins from amino acids.

• Absorptive State: Period after eating.

Step-by-Step Guidance

1. Recall what cells do with amino acids after a meal.

2. Think about anabolic processes.

3. Fill in the blank with the main use.

Try solving on your own before revealing the answer!

Final Answer: Protein synthesis

Amino acids are primarily used for building proteins during the absorptive state.

Q34. During the postabsorptive state, when we exercise, the anaerobically produced lactic acid is carried to the liver for ____________________________________________.

Background

Topic: Lactic Acid Metabolism – Postabsorptive State

This question is about the fate of lactic acid produced during anaerobic exercise.

Key Terms:

• Cori Cycle: Conversion of lactic acid to glucose in the liver.

• Gluconeogenesis: Formation of glucose from non-carbohydrate sources.

Step-by-Step Guidance

1. Recall what happens to lactic acid after exercise.

2. Think about the process in the liver that recycles lactic acid.

3. Fill in the blank with the correct process.

Try solving on your own before revealing the answer!

Final Answer: Conversion to glucose (via the Cori cycle)

Lactic acid is converted back to glucose in the liver.

Q35. Which of the series in the cellular respiration processes uses oxygen in the last reaction of the series? _____________.

Background

Topic: Cellular Respiration – Oxygen Utilization

This question is about the step in cellular respiration where oxygen is used as the final electron acceptor.

Key Terms:

• Electron Transport Chain (ETC): Uses oxygen in the final step.

• Oxidative Phosphorylation: ATP production using oxygen.

Step-by-Step Guidance

1. Recall the steps of cellular respiration: glycolysis, Krebs cycle, electron transport chain.

2. Think about which step requires oxygen as the final electron acceptor.

3. Fill in the blank with the correct series.

Try solving on your own before revealing the answer!

Final Answer: Electron transport chain

Oxygen is used in the last reaction of the electron transport chain.