What is the word equation for photosynthesis?
Carbon dioxide + water —-> glucose + oxygen
What type of reaction in photosynthesis?
Endothermic
During photosynthesis what is the energy from sunlight converted to?
Chemical energy in the form of glucose molecules
What factors affect photosynthesis?
Temperature
Carbon dioxide concentration
Light intensity
Chlorophyll concentration
How does temperature affect rate of photosynthesis?
Increase temp mean increased rate. This is because more energy is provided for the reaction. As the temperature reaches 45 degrees the rate of photosynthesis drops to zero because the enzymes become denatured
How does carbon dioxide levels affect the rate of photosynthesis?
As carbon dioxide increase so does the rate
This is because carbon dioxide is needed in the reaction
After a certain point it is no longer the limiting factor
How does light intensity affect rate of photosynthesis?
As light intensity increases, so does the rate
More energy is provided for the reaction
How does chlorophyll concentration affect rate of photosynthesis?
As it decrease so does rate
Less light can be trapped
What is it called when you double the distance between lamp and pondered and the light intensity reduces by a quarter?
Inverse square law
What can the glucose produced in photosynthesis be used for?
Used for respiration
Converted into insoluble starch for storage
Used to produce fat or oil for storage
Used to produce cellulose which strengthens cell walls
Used to produce amino acids for protein synthesis
What type of reaction is respiration?
Exothermic
What does respiration do?
Releases energy from glucose molecules for use by the body
Why do organisms need the energy released during respiration?
Chemical reactions to build larger molecules
For movement
To keep warm
Respiration in cells can be __________ (with oxygen) or _____________ (without oxygen)
Aerobic
Anaerobic
What is the word equation for aerobic respiration?
Glucose + oxygen —–> carbon dioxide + water
In aerobic respiration, what is not fully broken down?
Glucose
Energy transfer is much ________ in anaerobic respiration than aerobic respiration
Less
What is the word equation for the anaerobic respiration that occurs in animals?
Glucose —–> lactic acid
What is the word equation for anaerobic respiration in plants and yeast?
Glucose —-> ethanol+ carbon dioxide
What is anaerobic respiration in yeast called?
Fermentation
What is anaerobic respiration important for in manufacturing?
Bread and alcoholic drinks
What does the body demand more during exercise?
More energy
During exercise the body demands more energy. So what happens?
Rate of respiration increases
What all increase when the respiration rate increases?
Heart rate
Breathing rate
Breath volume
Why do Heart rate, Breathing rate and Breath volume all increase during exercise?
To supply the muscles with more oxygen and glucose for the increase in aerobic respiration
When does anaerobic respiration start to happen?
During vigorous activity when the muscle are not getting enough oxygen
What does anaerobic respiration cause in the body?
Build up of lactic acid and creates oxygen debt
What does the build up of lactic acid cause in the body?
Muscles to hurt and stops them contracting efficiently
Why does lactic acid need getting rid of quickly?
It is poison
Once exercise is finished, the oxygen debt must be __________
‘Repaid’
What happens to the lactic acid after exercise?
Blood flowing through muscles transports the lactic acid to the liver where it is broken down
What is oxygen debt?
The amount of extra oxygen the body needs after exercise to react with the lactic acid and remove it from cells
What is metabolism?
The sum of all the chemical reactions in a cell or in the body
What are the chemical reaction in a cell or body controlled by?
Enzymes and many need a transfer of energy
What is the energy in respiration used for in metabolism?
Energy is transferred by respiration and used to make new molecules
What is the energy transferred by respiration used to build specifically?
The conversion of glucose to starch, glycogen and cellulose
Formation of lipid molecules from a molecule of glycerol and three molecules of fatty acids
The use of glucose and nitrate ions to form amino acids, which are used to synthesise proteins
The breakdown of excess proteins into urea for excretion