Topic 4 - Bioenergetics Flashcards
How is energy transfered to plant from environment
By light
How do muscles store glucose
As glycogen
5 uses of gucose in plants
- Store as starch
- making Cellulose
- making Amino acids
- Respiration -
stored as Fats/oils
Why do plants store glucose as starch
-Starch is insoluble, so better to store as starch as too much glucose means too much osmosis so cells will become turgid and burst
Where is starch stored in plant and why
Roots, stem, leaves, so ready to use when no photosynthesis is happenig
2 examples of larger molecules → smaler ones
Glucose in respiration
Excess protein broken down into urea, excreted in urine
What is starch a storage molecule in
Plants
What is glycogen a storage molecule in
Animals
What is meant by not fuly oxidised
Doesn’t combine fuly with oxygen
What does oxygen debt do to breathing rate and pulse after exercise and why
-Increase it while co2 and lactic acid levels high to get more oxygen in blood to muscles
How light intensity and distance linked
Inversly proportional
What is inverse square law
light intensity indirectly proportional to 1/distance2
Oxygen plus lactic acid → ?
Harmless carbon dioxid and water
What is oxygen debt
Amount of extra oxygen body nees to reat with built up lctic acid and remove it from cells
Word equation for aerobic respiration
Glucose + water → carbon dioxide + water
Word equation for anaerobic respiration in muscles
Glucose → lactic acid
Balanced photosynthesis equation
6CO2 + 6H2O → C6H12O + 6O2
Is photosynthesis exo or endo + meaning
Endo - energy transfered from environment
4 limiting factors of photosynthesis
- Light intensity
- CO2 concentration
- Temperature
- Aount of chlorophyll
Limiting factor in winter
temp
Limiting factor at night
light intensity
Limiting factor when theres enough light and heat
carbon dioxide or chlorophyll
When is chlorophyll a limiting factor
disease/ ion defficiency
What are amino acids made of
glucose and nitrate ions
What do nitrate ions and glucose ions make
Amino acids
What is a limiting factor
Something that slows the rrate of photosynthesis or is preventing it happening faster
Word equation for anaerobic respiration in yeast
Glucose → carbon dioxide + ethanol
What happens to rate of photosynthesis if temperature is too hot, why and what temp
decreases as enzyme denatures
around 450C
If lamp is 10cm away, what is light intensity
1/102= 0.01 au
How is light intensity measured
Au, arbitary units
Advantage of greenhouse
Can control temp, carbon dioxie and lih intensity
What is respiration
Process of transfering glucose to energy
Respiration: endo or exo and meaning
Exo: transfers energy to environment
3 ways organisms use energy from respiration
- Building larger molecules from smaler
- In animals, allow muscles to contract
- in mammals and birds to keep body temp steady
What is metabolism
Sum of all the chemical reactions in an organism
3 examples of smaller molecules → larger ones
- glucose → starch, glycogen and cellulose
- 1 molecule glycerol + 3 fatty acids → lipid molecule
- Nitrate ions + glucose → amino acids → proteins
What is aerobic respiration
Respiration with oxygen present
What is anaerobic respiration
Respiration without oxygen- incomplete breakdown of glucose
Disadvantages of anaerobic respiration + why
Doesnt transfer as much energy as glucos no fully oxidised, and lactic acid causes muscle fatigue
Plant and yeast anaerobic respiration
glucose → ethanol + carbon dioxide
Name of anaerobic respiration in yeast
Fermentation
why do you respire when doing exercise
Muscles contract more so ore energy needed
Why breathing rate and volume increase when exercising
To get more oxygen into the blood
why heart rate increases when exercising
To get more oxygenated blood around body faster and remove carbon dioxide faster
2 ways to remove actic acid
- Oxygen combining with it to produce harmless CO2 and water
- Blood to liver to convert it back to glucose
1 way to control greenouse temp in winter
Heater
1 way to control grennouse temp in summer
Ventilation
1 way to control greenhouse light intensity at night
Artificial light
1 way to control greenhouse CO2 levels + how it works
parafin heater - when burns, CO2 is a by-product
What happens to mucles when become fatigued
They stop contracting as efficiently