2.8 Cell respiration Flashcards
Cellular respiration
Gradual and controlled release of energy by breaking down organic compounds to produce ATP molecules
3 main processes of cellular respiration in humans and where they occur
- Glycolysis (cytoplasm)
- Krebs cycle (Matrix of mitochondria)
- Electron transport chain (Inner mitochondrial membrane)
ATP
Molecule that carries energy within the cell for biochemical processes
Is ATP hydrolyzed or condensed to produce energy?
Hydrolyzed
What does ATP allows us to do?
Basic functions to maintain life like thinking, moving, digestion, conducting nerve signals and breathing
Difference between respiration and breathing
Breathing is physical inhalation and exhalation while respiration is breakdown of organic compounds and ATP production
What is the substrate in respiration?
Glucose
ATP + H2O
ADP + Inorganic phosphate + energy released from high energy bond
Which process is involved in anaerobic respiration?
Only glycolysis as others require oxygen
2 types of anaerobic respiration
Alcoholic fermentation and lactic fermentation
Formula for lactic fermentation
Glucose–> Lactate + 2 ATP molecules
Formula for alcohol fermentation
Glucose–> Ethanol + Carbon dioxide + 2 ATP
Two organic molecules besides glucose that can be used for respiration
Lipids and proteins
How does yeast help in baking? Refer to anaerobic process
Yeast respires anaerobically to produce ethanol and CO2. CO2 helps bread rise as it gets trapped and makes bubbles while ethanol is evaporated due to heat
Give one example of when humans respire anaerobically and why
During running or strenuous exercise, muscles need ATP to continue even after oxygen is used up. Although only 2 ATP is produced, power of muscle contractions can be maximized
Oxygen debt
Demand for oxygen that builds up during period of anaerobic respiration
In aerobic, is glucose oxidized or reduced?
It is oxidized
Why is there increased ATP production in aerobic?
It goes through all 4 steps of cellular respiration which yields potential energy at each step
Glucose + oxygen
CO2 + H2O + Energy
What is used to measure rate of respiration and how does it measure?
Respirometer. It uses oxygen consumption as an indicator
Respirometer: Purpose of filter paper wicks
Rolled up to increase efficiency of CO2 absorption
Respirometer: Purpose of KOH
KOH absorbs CO2 so changes in pressure due to oxygen can be observed
Respirometer: Purpose of capillary tube
Movement in oil per minute allows us to measure rate of O2 consumption and volume if diameter is known
Respirometer: Purpose of syringe
Used to reset position of colored oil for repeat tests
Respirometer: Purpose of rubber bungs
Closes system to prevent changes in air volume not due to respiration
Respirometer: Purpose of metal cage
Keeps organism in place and away from KOH
Respirometer: Purpose of water bath
To control for temperature as that can affect pressure
Respirometer: Purpose of control tube
Ensures changes are all due to respiration and not reaction of KOH with other gases
What does ATP consist of?
Adenosine + triphosphate linked by high energy bonds
Ethical and environmental concerns of using animals in respirometers
- Removing animals from their natural habitat should have no dire effects and they should be safely returned to population
- Animals should not suffer
- Will hydroxide have an impact on their body, reaction or genetics
- Is using animals essential or are there alternatives?
Which reaction is water produced in?
Aerobic respiration
How is bioethanol produced? Reference function of yeast
- Starch and cellulose in plants are broken down into sugars
- Fermenters keep yeast in optimum conditions
- Yeast respires, sugar in plants get converted to ethanol and carbon dioxide
- Ethanol is purified by distillation and water is removed to improve combustion
Why is anaerobic respiration done for short periods of time?
There is a limit to the concentration of lactate the body can withstand
