Definition: Enzymes are biological catalysts that speed up chemical reactions and are highly specific to their substrates.

Example: Carbohydrase breaks down starch into simpler sugars, demonstrating enzyme specificity.

Highlight: Temperature and pH significantly affect enzyme activity, with optimal function at 37°C for most human enzymes.

Vocabulary: Emulsification - the process of breaking down large fat droplets into smaller ones, facilitated by bile.

Definition: Double circulation refers to blood passing through the heart twice - once through the pulmonary circulation and once through the systemic circulation.

Example: Arteries have thick walls to withstand high pressure, while veins have valves to prevent backflow.

Highlight: Blood components each serve specific functions: red blood cells for oxygen transport, white blood cells for immune response, and platelets for clotting.

Vocabulary: Phagocytosis - the process where white blood cells engulf and destroy pathogens.

Definition: Coronary heart disease occurs when arteries supplying the heart muscle become blocked by fatty deposits.

Example: Lifestyle factors such as smoking and obesity significantly increase cancer risks.

Highlight: Prevention strategies include maintaining a healthy diet and regular exercise to reduce the risk of cardiovascular disease.

Vocabulary: Atherosclerosis - the buildup of fatty deposits in arteries leading to restricted blood flow.

Definition: Eukaryotic cells contain a true nucleus and membrane-bound organelles, while prokaryotic cells lack these features.

Example: Plant cells demonstrate eukaryotic characteristics with specialized structures like chloroplasts for photosynthesis and cell walls for support.

Highlight: Cell differentiation is a crucial process where cells become specialized for specific functions, with plant cells retaining this ability throughout their lifecycle while animal cells lose it early.

Vocabulary: Binary fission - the process of bacterial cell division occurring approximately every 20 minutes.