Bioenergetics Flashcards
What is photosynthesis?
An endothermic reaction in which energy is transferred to chloroplasts from the environment by light
What is the word equation for photosynthesis?
Carbon dioxide + water > glucose + oxygen
What is the formula equation for photosynthesis?
6CO2 + 6H2O > C6H12O6 + 6O2
What are the 4 uses of glucose in plants?
1: respiration - energy is transferred from glucose
2: strengthening cell walls - glucose is converted into cellulose, which is used to make strong cell walls
3: protein synthesis - glucose and nitrate ions (from soil) are used to make amino acids, which are then made into proteins
4: energy storage - glucose is turned into lipids or insoluble starch to store energy
How do you increase the rate of photosynthesis?
1: light intensity
2: temperature
3: CO2 concentration
4: amount of chlorophyll
Any of these factors can become the limiting factor (thing that stops photosynthesis happening any faster)
What is the inverse square law?
Light intensity [weird alpha symbol] 1/distance (d)^2
What 4 things are in a greenhouse to control limiting factors?
1: heaters (paraffin ones for CO2)
2: shades
3: lamps
4: ventilation
What is respiration?
The process of transferring energy from glucose. It’s an exotérmica reaction that goes on continuously in living cells
what 3 things is respiration used for?
1: to contract muscles for movement
2: to keep warm (in mammals and birds)
3: to build up larger molecules from smaller ones
What is the word equation for aerobic respiration?
Glucose + oxygen > carbon dioxide + water
What is the formula equation for aerobic respiration?
C6H12O6 + 6O2 > 6CO2 + 6H20
What is anaerobic respiration?
Respiration without oxygen
It transfers much less energy than aerobic respiration because glucose isn’t fully oxidised
What is anaerobic respiration in muscle cells?
Glucose > lactic acid
What is anaerobic respiration in plant and yeast cells?
Glucose > ethanol + carbon dioxide
What is anaerobic respiration called in yeast cells?
Fermentation
What is metabolism?
The sum of all the reactions that happen in a single cell or the body.
Metabolic reactions use energy from respiration to make new molecules
What are 3 metabolic reactions?
1: Glucose and nitrate ions combines to make amino acids, then made into proteins
2: Lipids broken down into glycerol and fatty acids
3: glucose molecules joined together to make bigger carbohydrates (eg, starch or glycogen)
What are the effects or exercise on the body?
Exercise > more energy needed > more aerobic respiration needed > more oxygen needed
What 3 things can be increased to get more oxygen into the body?
1: heart rate
2: breathing rate
3: breath volume
What is oxygen debt?
The amount of extra oxygen needed to react with built-up lactic acid and remove it from cells.
During vigorous exercise, not enough oxygen is supplied to the muscles.
What does not getting enough oxygen to the muscles mean?
Anaerobic respiration takes place in muscles > lactic acid builds up in muscles > oxygen debt created > heart rate and breathing rate stay high after exercise to repay oxygen debt
How does the liver help with oxygen debt?
Blood goes to the muscle, takes out the lactic acid, returns to the liver. In the liver the lactic acid is converted into glucose.
