Cell Respiration (SL) - Review Flashcards

A comprehensive set of practice flashcards covering ATP structure and function, cellular respiration (aerobic vs anaerobic), glycolysis, Krebs cycle, ETC, fermentation, substrates, respirometry, and factors affecting respiration. Suitable for review of SL Biology concepts from the provided notes.

What is ATP and why is it important in cells?

ATP is a nucleotide (adenine + ribose + three phosphate groups) that distributes energy within cells; energy is released when the outermost phosphate bond is hydrolyzed, forming ADP and Pi.

Name two or more life processes that use ATP.

Movement (muscle contraction), growth and repair (cell division), active transport across membranes, synthesis of biomolecules (anabolism), and nerve transmission.

Where does glycolysis occur?

In the cytoplasm of the cell.

Where does aerobic respiration take place?

In the mitochondria (mitochondrion) of the cell.

Where does anaerobic respiration take place?

In the cytoplasm (cytosol).

What are the main substrates used in cellular respiration?

Carbohydrates (primarily glucose); lipids and proteins can also be used.

Write the word equation for aerobic cellular respiration.

Glucose + O2 → CO2 + H2O + ATP (approximately 36 ATP per glucose).

Write the word equation for anaerobic respiration in animals.

Glucose → Lactate + a small amount of ATP (net ~2 ATP).

Write the word equation for anaerobic respiration in yeast/plants.

Glucose → Ethanol + CO2 + a small amount of ATP (fermentation).

What is produced during glycolysis?

Glucose is split into 2 pyruvate; net 2 ATP are produced; 2 NADH are formed.

Where is the Krebs cycle located?

In the mitochondrial matrix.

Where is the electron transport chain located?

In the inner mitochondrial membrane.

What is fermentation and when does it occur?

Fermentation is anaerobic metabolism that regenerates NAD+ to allow glycolysis to continue without oxygen; lactate is produced in animals, ethanol and CO2 in yeast/plants.

What are the two main types of anaerobic respiration?

Lactate fermentation (animals) and ethanol fermentation (yeast/plants).

What is the energy yield of anaerobic respiration per glucose?

About 2 ATP per glucose (net), since glycolysis yields 2 ATP and fermentation does not produce additional net ATP.

What is the purpose of a respirometer?

To measure an organism's respiration rate by monitoring O2 consumption and CO2 production (via changes in gas volume/pressure).

What are the key components of a respirometer setup?

A sealed platform with the specimen, a CO2 absorbent (e.g., soda lime), a manometer to detect pressure changes, and a control/absorbent vessel of equal volume.

How is respiration rate calculated with a respirometer?

Rate = volume of gas used ÷ (time × mass of organism). Example units: mm3 min−1 g−1.

What factors can affect the rate of cellular respiration?

Temperature, hydration, light (plants only), age, and activity levels of the organism.

Define gas exchange, respiration, and ventilation.

Gas exchange: diffusion of O2/CO2 between alveoli and blood; respiration: cellular transfer of energy from organic molecules to ATP; ventilation: movement of air into and out of the lungs.

Compare aerobic and anaerobic respiration in terms of oxygen use and ATP yield.

Aerobic respiration requires O2 and yields about 36 ATP per glucose; anaerobic respiration occurs without O2 and yields about 2 ATP per glucose.

Are lipids and proteins used in cellular respiration?

Yes, lipids and proteins can be digested and fed into respiration pathways in addition to glucose.

Why must cellular respiration continuously occur in organisms?

Because energy stored in ATP is released as heat when used; ATP must be continually regenerated by aerobic respiration using glucose and oxygen.

What are the two main energy transformations involved in ATP cycling?

Hydrolysis of ATP to ADP + Pi releases energy; condensation of ADP + Pi reforms ATP and stores energy.

Approximately how many ATP molecules are produced per day per person in the body according to the notes?

The notes mention roughly body-weight in ATP molecules per day (approximately 7.5 × 10^25 ATP molecules).