§-Section

Cells, enzymes and energy (Module 2)

6 dot points, in syllabus order. Each dot point has a focused answer, with exam-style questions and worked answers where available.

How do enzymes control the chemical reactions of life?

Enzymes: structure and function (globular protein, active site, denaturation); factors affecting rate of reaction (temperature, pH, enzyme concentration, substrate concentration, inhibitors, coenzymes and cofactors); competitive and non-competitive inhibitors; coenzymes and cofactors (general understanding only)

TASC Biology Level 3 (BIO315124, criterion 5): enzymes as globular proteins with a specific active site, the lock-and-key and induced-fit models, denaturation, and how temperature, pH, enzyme and substrate concentration, competitive and non-competitive inhibitors, and coenzymes and cofactors affect reaction rate.

8 min read →

How is light energy captured and used to make glucose in the chloroplast?

Photosynthesis: the role of chloroplasts (thylakoids, stroma and grana); inputs and outputs as a balanced net chemical equation; factors affecting rate of reaction (temperature, carbon dioxide concentration and light intensity); a general understanding of the light-dependent and light-independent stages

TASC Biology Level 3 (BIO315124, criterion 5): the chloroplast (thylakoids, grana, stroma), the balanced net equation for photosynthesis, a general account of the light-dependent and light-independent stages, and how light intensity, carbon dioxide concentration and temperature affect the rate, including limiting factors.

8 min read →

How do cells release usable energy from glucose, with and without oxygen?

Respiration: the role of mitochondria in aerobic respiration; the main stages of anaerobic and aerobic respiration (glycolysis, the Krebs cycle and the electron transport chain); inputs and outputs as balanced net chemical equations; factors affecting rate of reaction (temperature, glucose concentration, oxygen concentration and pH)

TASC Biology Level 3 (BIO315124, criterion 5): the role of mitochondria, glycolysis, the Krebs cycle and the electron transport chain, where each happens and how much ATP it yields, anaerobic respiration in animals and in plants and yeast, the balanced equations, and the factors that affect the rate.

9 min read →

How does the structure of each organelle suit its function?

Identify the main organelles of eukaryotic cells and relate their structure to function.

The structure and function of the nucleus, mitochondria, chloroplasts, endoplasmic reticulum, Golgi, ribosomes, and other organelles, and how compartments organise the cell (TASC Biology Level 2 content, not examined in Level 3 BIO315124).

8 min read →

Why are cells small and why do large organisms have many cells?

Explain how the surface area to volume ratio limits cell size and exchange.

How surface area to volume ratio limits cell size, controls exchange rates, and explains adaptations that increase exchange surfaces (TASC Biology Level 2 content, not examined in Level 3 BIO315124).

7 min read →

How does the cell membrane control what enters and leaves a cell?

Describe the structure of the cell membrane and explain the mechanisms of membrane transport.

The fluid mosaic model of the membrane and the mechanisms of diffusion, osmosis, facilitated diffusion, active transport, and bulk transport (TASC Biology Level 2 content, not examined in Level 3 BIO315124).

8 min read →