RESPIRATION
- RESPIRATION is a set of metabolic reactions that take place in the cells of organisms.
- Respiration is a chemical process that TRANSFERS ENERGY by breaking down GLUCOSE.
- Respiration is an EXOTHERMIC process, meaning it release energy to the surroundings, which can be observed as HEAT.
Uses of Respiration
The energy transferred from respiration supplies all the energy needed for living processes including:
- KEEPING WARM and maintaining a constant warm body temperature.
- Contracting muscles for MOVEMENT.
- Carrying out chemical reactions to build LARGER MOLECULES from smaller ones (eg. Turning amino acids into proteins)
Types of RESPIRATION
1. AEROBIC RESPIRATION:
- Occurs with OXYGEN and is the most EFFICIENT way to release energy from glucose.
- Takes place CONTINUOUSLY in animals and plants, within the MITOCHONDRIA.
The word and symbol equations for aerobic respiration are:
- Word Equation: Glucose + Oxygen → Carbon dioxide + Water
- Symbol Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O
2. ANAEROBIC RESPIRATION:
- Happens when there is NOT ENOUGH OXYGEN available, such as during intense EXERCISE.
- This form of respiration does NOT produce as much energy because the oxidation of glucose is INCOMPLETE.
In MUSCLE cells, glucose is converted into LACTIC ACID.
- Equation: Glucose → Lactic acid
In PLANTS and YEAST, glucose is converted into ETHANOL and carbon dioxide.
- Equation: Glucose → Ethanol + Carbon dioxide
FERMENTATION
A type of anaerobic respiration in YEAST, which is widely used in the FOOD and DRINKS industry. It is valuable for:
1. Bread Making
The carbon dioxide released from the process causes the bread to RISE.
2. Making Alcoholic Drinks
The ethanol produced makes alcoholic drinks such as BEER and WINE.
