Unit 1: Respiration From Achieve Flashcards
State how chemical energy in glucose is released
When glucose is broken down, bonds are broken, and this releases energy.
State how ATP is made and examples of process that requires energy
The living organisms are unable to use energy from glucose directly and so uses it to produce an energy rich molecule which the body can use. This molecule is ATP.
The energy from the breakdown of glucose is used to build up ATP from ADP and Pi.
Energy in
ADP+Pi——————->ATP
When energy is needed, the reverse happens. ATP is broken down into ADP and Pi releasing energy. This energy used for a number of cellular processes.
Energy out
ATP————————> ADP+Pi
Examples of cellular processes that use energy are:
Protein synthesis
Cell division
Muscle contraction
Transmission of nerve impulses
Some energy is also lost as heat.
Describe the stages of aerobic respiration
Aerobic respiration is the breakdown of glucose in the presence of Oxygen.
Stage 1
Glucose → Pyruvate
This yields a small quantity of ATP.
Stage 2 (oxygen required)
Pyruvate → Carbon Dioxide + Water
This yields a large amount of energy.
The products here are carbon dioxide and water, completing the full breakdown of glucose.
Summary
Respiration can be summarised in the following equation:
Glucose + Oxygen → Carbon Dioxide + Water (ATP)
Describe the process of aerobic respiration from cytoplasm and mitochondria
It starts in the cytoplasm and ends in the mitochondria.
It initially yields 2 molecules of ATP (stage 1) and further releases a lot of energy to produce a large number of ATP.
As most energy is produced in the mitochondria, cells requiring a lot of energy will have a lot of mitochondria in comparison to other cells.
Describe fermentation in animal cells, stating the location and the quantity of energy released
Fermentation in animals is the breakdown of glucose in the absence of oxygen.
Glucose → Pyruvate ↔ Lactate
The product of this reaction is Lactate. This reaction is reversible, and lactate can be converted back into pyruvate in the presence of oxygen.
It only takes place in the cytoplasm and only releases a small amount of energy, enough to produce only the initial 2 molecules of ATP.
Describe fermentation in plant and fungal cells, stating the location and the quantity of energy released
Fermentation in plants and fungal cells is the breakdown of glucose in the absence of oxygen.
Glucose → Ethanol + Carbon dioxide
The products of fermentation here are Ethanol and carbon dioxide. This reaction is not reversible due to the loss of carbon dioxide.
It only takes place in the cytoplasm and only releases a small amount of energy, enough to produce only the initial 2 molecules of ATP.
