Respiration and Photosynthesis Vocabulary

Biochemical Processes

Biochemical processes are chemical reactions in living things. Respiration releases energy from food, while photosynthesis uses energy to make food.

Respiration

Respiration is the release of energy from food. Aerobic respiration requires oxygen, while anaerobic respiration does not.

• Aerobic Respiration Equation: $glucose + oxygen \rightarrow carbon dioxide + water + energy$

Aerobic Respiration

Most living things use aerobic respiration to get energy from food for movement, growth, warmth and repair.

• Glucose is transported by blood plasma.
• Oxygen is carried by haemoglobin in red blood cells.
• Aerobic respiration occurs in cytoplasm and finishes in mitochondria.

Factors Affecting Respiration

• Temperature: Enzymes control biological reactions, and temperature affects enzyme activity. Human enzymes work best at 37°C, while plant enzymes work best between 20°C and 30°C.
• Oxygen: Essential for aerobic respiration. Shortage of oxygen leads to anaerobic respiration.

Anaerobic Respiration

Occurs when there is a shortage of oxygen; it breaks down glucose without oxygen, producing less energy and harmful waste products.

• In humans: $glucose \rightarrow lactic acid + a small amount of energy$
• In yeast cells: $glucose \rightarrow alcohol + carbon dioxide + a small amount of energy$

Products of Respiration

• Energy: Used by living things.
• Carbon Dioxide: Waste product released into the air (animals) or used for photosynthesis (plants).
• Water (Vapour): Waste product released into the air by plants and animals.