Bioenergetics Flashcards
Where does photosynthesis occur?
Chloroplasts
What’s the balanced equation for photosynthesis?
6CO2 + H2O ————> C6H12O6 + 6O2
What do plants use glucose for?
Respiration (for energy) Making cellulose (to make cell walls) Making amino acids (to make proteins) Stored as oils and fats, lipids. Stored as starch (to use when photosynthesis can’t occur)
What factors affect photosynthesis?
Light intensity
Temperature
CO2
Sometimes chlorophyll
How can we measure the effect of light intensity on photosynthesis?
Set up a boiling tube containing of sodium hydrogencarbonate solution.
Cut a piece of the pondweed.
Place the pondweed in the boiling tube.
Position the pondweed 10 cm away from the boiling tube. Allow the boiling tube to stand for five minutes. Count the number of bubbles emerging in one minute.
Repeat the count five times and record your results.
Calculate the average number of bubbles produced per minute.
Repeat the experiment at different distances away from the light source.
What e the link between light intensity and distance?
light intensity is inversely proportional to distance2
Why are greenhouse useful?
It can create conditions for farming.
You can control temperature inside with a heater or shaded/ventilator, light by using artificial light, carbon dioxide by using a paraffin heater, and keep plants free from diseases.
A downside is it’s expensive.
What’s respiration?
The process of transferring energy from glucose
What’s the energy used for?
Building larger molecules
Allows muscles to contract (animals)
Keep body temperature constant (animals and birds)
What’s metabolism?
All the chemical reactions in the cells of an organism.
Give an example of larger molecules being made from small ones.
Lots of small glucose molecules can form starch, glycogen, and cellulose when joined together.
Give an example of large molecules being broken down into smaller ones.
Excess protein is broken down to produce urea
What are the two tires of respiration?
Anaerobic and aerobic
What’s the difference between anaerobic respiration and aerobic respiration?
Aerobic respiration uses oxygen whilst anaerobic is without oxygen.
What’s the word equation for aerobic respiration?
glucose + oxygen ——> carbon dioxide + water
What’s the word equation for anaerobic respiration?
glucose ———> lactic acid
When do you use anaerobic respiration?
When your body can’t supply enough oxygen to your muscles.
What’s anaerobic respiration called in yeast cells and what’s the word equation?
Fermentation
glucose ——-> ethanol + carbon dioxide
What happens when you exercise?
Your muscles contract more frequently so you need more energy, which comes from increased respiration. But we also need more oxygen so our breathing rate, breathing volume and heart rate all increase to take more oxygen and get it around the body faster.
If the exercise is very vigorous, you’ll start breathing anaerobically but it causes lactic acid in your muscles, causing pain. When you’re done exercising, you’ll have an oxygen debt
What’s oxygen debt?
The amount of extra oxygen needed to react it with the lactic acid and remove it from the cells. (it produces carbon dioxide and water)
