1 life processes - respiration and movement, page 12-18, 23-24 Flashcards
What is respiration?
A chemical reaction which taking place in cells, where glucose is broken down to release energy.
What can ATP be used for?
- Contraction of muscle cells, producing movement.
- Active transport of molecules and ions.
- Building large molecules, such as proteins.
- Cell division.
What is ATP also known as?
Energy. It provides energy for cells.
What is aerobic respiration?
A reaction that releases energy from food. Uses oxygen and produces carbon dioxide and water.
What is the word equation for aerobic respiration?
Glucose + Oxygen —> Carbon dioxide + water + energy
What is the chemical equation for aerobic respiration?
C6H12O6 + 6O2 —> 6CO2 + 6H2O
Where does aerobic respiration occur?
In the cells of humans, animals, plants and many other organisms. More specifically, in the mitochondria.
How is ATP used during respiration?
There is ADP, meaning that there are only 2 phosphate groups. Respiration adds the final phosphate group; turning it into ATP - with three phosphate groups.
How is ATP used by other cells?
The ATP is composed of three phosphate groups. When energy is needed; this ATP loses one phosphate group and gets turned into ADP.
What is anaerobic respiration?
The reaction that releases energy from food, without using oxygen. Produces lactate in mammals, carbon dioxide and ethanol in yeast.
What is anaerobic respiration in terms of glucose?
Not all the glucose is broken down, so less energy is released. It can occur in situations when oxygen is in short supply.
What kind of organisms use anaerobic respiration?
- Muscle cells.
- Yeast.
What is yeast?
Single-celled fungi.
How does yeast respire anaerobically?
When yeast cells are prevented in getting enough oxygen, they stop respiring aerobically and start to respire anaerobically instead. The glucose is broken down into ethanol and carbon dioxide.
What is the word equation for anaerobic respiration in yeast?
Glucose —> Ethanol + Carbon dioxide (+ some energy)
How do muscle cells respire anaerobically?
When they are short of oxygen. If the muscles are overworked, the blood cannot reach the cells fast enough to deliver enough oxygen for respiration. So when someone does a ‘burst’ activity; like a sprint or quickly lifting a heavy weight.
What is the word equation for anaerobic respiration in muscle cells?
Glucose —> Lactic acid (+ some energy)
What happens to the lactate after the excersise?
The lactate is respired aerobically in the mitochondria.
What is oxygen debt?
The volume of oxygen that is needed to completely oxidise the lactate built up during a period of anaerobic respiration.
What is the practical that investigate the production of carbon dioxide by small living organisms?
Uses hydrogen carbonate solution which is orange - it turns yellow if carbon dioxide is added to it. The indicator is sensitive to small changes in carbon dioxide levels making it suitable for small living organisms.
What is the method used?
- The living organisms are placed in a stoppered boiling tube.
- The small organisms are placed on a gauze platform.
- Below them is hydrogen carbonate indicator solution which will turn yellow when they respire as it has sensed carbon dioxide.
Why are the living organisms placed on a gauze platform?
To avoid their exposure to the chemical.
What is the investigation used to demonstrate that heat is produced by respiration?
- Peas are soaked in water for 24 hours.
- One batch of peas are boiled - to kill them.
- Both batches are placed in a bleach solution to act as a disinfectant and then they are washed twice with distilled water to get rid of any traces of bleach.
What is the method used to demonstrate that heat is produced by respiration?
Each batch is placed into an inverted vacuum flask and some air will be left in it. The inverted flash and cotton wool allow carbon dioxide to escape as it might kill the peas.
