Key Area 6: Respiration Flashcards
Respiration
the cellular process that releases energy from food and stores it as ATP.
Glucose
the main source of chemical energy in a living cell
ATP
a molecule that stores and transfers energy in cells
Pyruvate
key intermediate molecule in metabolism
Aerobic respiration
a chemical process that uses oxygen to break down nutrients and produce energy
Fermentation
a metabolic process that breaks down glucose without oxygen to produce energy
Lactate
the deprotonated form of lactic acid, which is a substance produced when the body breaks down glucose without oxygen
Carbon dioxide and ethanol
Cytoplasm
the fluid that fills the inside of a cel
Mitochondria
Where aerobic respiration takes place and ATP is produced in the cell.
ADP
a biological molecule that plays a key role in the flow of energy in living organism
Chemical energy is released
when food is burnt as heat and light energy
In living cells chemical energy is released in a series of
enzyme controlled reactions in respiration
ATP —> ADP + Pi
releases energy
ADP + Pi —> ATP
requires energy
First stage of respiration
The breakdown of glucose, this is identical for aerobic respiration and fermentation
Second stage of respiration
The fate of pyruvate, this stage is different for aerobic respiration and fermentation pathways
The first stage of respiration takes place in the
Cytoplasm
Glucose is broken down in a series of enzyme controlled reactions to form ….. oxygen does ….
- two molecules of pyruvate, two ATP molecules
- not need to be present
Aerobic respiration takes place in the
Mitochondria
Aerobic respiration involves the breakdown of …. in a series of enzyme controlled reactions to release….
- Pyruvate
- carbon dioxide, water, and 18 molecules of ATP per pyruvate molecule
In aerobic respiration a total of … are produced for each ….
- 38 ATP
- original glucose molecule
In fermentation, … is present
no oxygen
In fermentation glucose is broken down to
2 ATP molecules per glucose molecule
Animal cells
glucose —> pyruvate —> lactate + energy
lactate can cause
muscle fatigue and an oxygen debt builds up
Pyruvate to lactic acid (animal)
is reversible
Plant and yeast cells
Glucose –> pyruvate —> ethanol and CO2 + energy?
pyruvate to ethanol and CO2 (p and y)
is and irreversible process
Fermentation takes place in the
cytoplasm
Aerobic respiration requires
oxygen
Fermentation does not require
oxygen
Stage 1 of aerobic respiration (cytoplasm)
Glucose —> 2 molecules of pyruvate
(+2 molecules of ATP)
Stage 2 of aerobic respiration (mitochondria)
Pyruvate + Oxygen —> CO2 + water
(+large number of ATP)
ATP is an energy-rich chemical compound. The energy released when the bond attaching to the
terminal phosphate is broken
In the absence of oxygen the … pathway takes place
fermentation
The higher the energy requirement of a cell thr greater the number of
Mitochondria present in the cell
… begins in the cytoplasm. the process of … is completed in the cytoplasm. whereas … is completed in the mitochondria
- Respiration
- Fermentation
- aerobic respiration
What is released as a waste product during aerobic respiration in yeast cells?
Water
