Topic 4 - Bioenergetics Flashcards
What is photosynthesis?
It is the process by which a plant uses energy to transfer carbon dioxide and water into glucose and oxygen.
Energy is transferred to chloroplasts through light.
Is photosynthesis endothermic or exothermic?
Endothermic - Energy is gained since its transferred from the environment.
What is the word and symbol equation for photosynthesis?
Carbon dioxide + water —–(light)—–> Glucose + Oxygen
6CO2 + 6H2O ——(light)—–> C6H12O6 + 6O2
What is glucose in plants used for?
Respiration Making cellulose Making amino acids Stored as oil or fats Stored as starch
What are limiting factors of the rate of photosynthesis?
Light intensity (night)
Concentration of CO2
Temperature(winter)
Amount of chlorophyll(disease)
What does the inverse square law show and what is the equation for it?
It shows that light intensity is proportional to 1/d^2
Light intensity (proportion symbol) 1/d^2
How can you artificially create an ideal environment for your plants?
Grow them in a greenhouse.
How are greenhouses helpful?
Trap suns heat so temperature doesnt become limiting.
You could put a heater if too cold or shades and ventilation if too hot.
Use artificial light after sun gone down.
Increase CO2 in greenhouse with paraffin heater.
Keep pests away
What is respiration?
Respiration is the process of transferring energy from the breakdown of glucose and it goes on in every cell in your body continuously.
What are some examples of how organisms use energy from respiration?
Build up larger molecules from smaller ones eg proteins from amino acids.
Used to allow muscles to contract.
Keep body temperature steady
What is metabolism?
The sum of all reactions that happen in a cell or the body is cal.ed its metabolism.
Whats the difference between aerobic and anaerobic respiration?
Aerobic respiration uses oxygen and glucose to produce carbon dioxide and water.
Anaerobic respiration uses only glucose and is the incomplete breakdown of glucose, making lactic acid.
When is anaerobic respiration useful?
In emergencies like during exercise and you dont have enough oxygen for aerobic respiration it allows you to keep on using your muscles for a while longer.
What is the word and symbol equation for aerobic respiration?
Opposite of photosynthesis
Glucose + oxygen ——> carbon dioxide + water
C6H12O6 + 6O2 ——> 6CO2 + 6H2O
What is the word equation for anaerobic respiration?
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 and when is yeast helpful?
Fermentation.
In bread-making carbon dioxide from fermentation of yeast is what makes the bread rise.
In beer and wine making, the fermentation process produces alcohol.
What happens when you exercise? (In terms of respiration)
Muscles need energy from respiration to contract. When you exercise your muscles contract more so you need more energy. Energy comes from increased respiration.
Your breathing rate and breath volume increase (get more oxygen into the blood)
Heart rate increase (pump oxygenated blood round body quicker).
Vigorous exercise (sprinting) your body cant supply enough oxygen so anaerobic respiration takes place.
What happens after anaerobic respiration?
You have an oxygen debt.
This is the amount of extra oxygen your body needs to react with the build up of lactic acid and remove it from your cells.
Oxygen reacts with lactic acid to form CO2 and water.
What does your body do whilst your in oxygen debt?
Breathing hard after a while after youve stopped exercise.
Pulse and breathing rate stay high.
Blood transports lactic acid to liver where its converted back to glucose.
How can you investigate effect of exercise on the body?
1) Measure breathing rate by counting breaths and heart rate by taking the pulse.
2) Record these 5 mins after walking, running, sitting etc.
3) Pulse rate will increase, the more intense the exercise is.
4) To reduce effect of random errors, do it as a group and record the average.
