4: Bioenergetics

Created by

Polly M

Cards (17)

Photosynthesis
The process by which plants make glucose from sunlight
Endothermic reaction in photosynthesis
Energy is transferred from the environment to the chloroplasts by light
Photosynthesis Equation
Carbon dioxide + water → glucose + oxygen
Factors affecting rate of photosynthesis
Temperature
Light intensity
Carbon dioxide concentration
Amount of chlorophyll
Core practical to calculate rate of photosynthesis
1. Pondweed in test tube
2. Capillary tube and syringe
3. Lamp at measured distance
4. Measure distance bubble moves to calculate oxygen volume
5. Control variables except independent variable
Limiting factor in photosynthesis
An environmental condition (such as light intensity) which, in low levels, restricts any increase in the rate of photosynthesis
Farmers can use knowledge of limiting factors to enhance greenhouse conditions for greater rate of photosynthesis
Inverse proportion
Relationship where one factor increases as another decreases
Uses of glucose from photosynthesis
For respiration
Converted into insoluble starch for storage
To produce fat or oil for storage
To produce cellulose to strengthen cell walls
Combined with nitrates to form amino acids which produce proteins
Respiration
The process of transferring energy from glucose so living processes can occur
Exothermic
Energy is transferred to the environment
Types of respiration
Aerobic
Anaerobic
Anaerobic respiration in animals
Glucose → Lactic acid
Anaerobic respiration in plants and yeast 
Glucose → Ethanol + Carbon dioxide
Oxygen debt 
The amount of extra oxygen the body needs after exercise to react with the accumulated lactic acid and remove it from the cells
Metabolism 
The sum of all the reactions in a cell or the body, controlled by enzymes
Metabolic reactions 
Glucose to starch, glycogen and cellulose
Glycerol and fatty acids to lipids
Glucose and nitrate to amino acids and proteins
Respiration reactions
Urea forming from protein breakdown