Unit 5 - energy transfer in and between organisms Flashcards
Stomata
Gaps on the lead surface to allow the mesophyll to access gases easily
Light dependent reaction
Conversion of water to electrons and protons by light
Photolysis
Splitting of water into electrons, protons and oxygen
Photoionisation
Sunlight falling onto chlorophyll exciting electrons which enter the ETC
Thylakoids
Disc like sacs in the chloroplast. Site of the light dependent reaction
NADP
Coenzyme crucial in photosynthesis. Carrier of protons when reduced
Light independent reaction
Conversion of RuBP into organic molecules. Follows movement of carbons and is cyclic
StromA
fluid filling the chloroplast
Site of the light independent reaction
Glycolysis
Conversion of glucose to pyruvate in both aerobic and anaerobic respiration
Link reaction
Conversion of pyruvate acetate and then acetyl coenzyme A
Kerbs cycle
Incorporation of acetylcoenzhne A into cycle that release NADH, FADH2, CO2 and ATP.
Oxidative phosphorylation
Final stage of aerobic respiration.
Uses electrons from coenzyme carriers as well as proton movement to generate ATP
Anaerobic respiration
Absence of oxygen
Used to regenerate NAD for glycolysis
Lactic acid produced in humans
Ethanol produced in plants
Saprobionts
Decompose organisms by releasing minerals back into the mineral cycles
Calorimetry
Method to measure chemical energy store of organisms
Net primary productivity
Total energy store remaining after considering respiratory losses as well as excretion
Nitrogen cycle
Involves ammonification Nitrification Nitrogen fixation Denitrification These ensure nitrate ions enter the food chain
Mutualistic nitrogen-fixing bacteria
Turn nitrogen gas into ammonia. Living on plant roots, they get carbs and plants get amino acids
Phosphorus cycle
Cycle that releases phosphate from rocks and oceans, is converted by plants and passed through the food chain
Leaching
Movement of excessive amounts of nutrients into waterways
Eutrophication
Process by which nutrient concentration in the water leads to algal bloom and development of putrid waterways
Location of glycolysis
Cytoplasm
Location of link reaction
Matrix
Location of kerbs cycle
Matrix
Location of electron transport chain and oxidative phosphorylation
In between outer and inner membrane of mitochondria
How many net ATO molecules are produced during glycolysis
2
How many ATP molecules released during link reaction
0
How many ATP molecules released during Krebs cycle
1
Name for the current theory by which respiration occurs
Chemiosmotic theory
What do animals convert pyruvate into?
Triphosphate
What are some methods used in intensive rearing of domestic livestock?
Use of hormones to increase growth rates
Selective breeding of animals to produce varieties that are more favourable
In livestock how is the energy converted into biomass increased?
- Restrict movement - reduce muscle contraction
- keep environment warm - less energy used to warm the body
- control feeding - prevent the cow eating as much fibrous food
- exclude predators - prevent higher trophic levels
Biomass
Total mass of a living material in a specific area at a given time
Can be measured in terms of mass of carbon or dry mass tissue per given area.
Dry biomass can be estimated using colorimetry
Consumers
These obtain their energy and nutrients by feeding other organisms rather than using the suns energy directly.
Can be primary, secondary or tertiary.
Producers
Photosynthetic organisms that manufacture organic substances using light energy, water, carbon dioxide and mineral ions
What does the relative inefficiency of energy transfer between tropic levels explain?
- most food chains only have 4-5 levels due to limited energy available (not enough to support another level)
- total biomass decreases at high levels
- total amount of energy is less available moving up
Net production to consumers calculation
Ingest food - (energy lost in faeces + respiratory loss)
NPP equation
NPP = GPP - respiratory losses
Gross primary production
Chemical energy store in plant biomass in a given area or volume
Why is only 1% and 3% of the suns energy available to be converted into organic matter by plants?
- Over 90% of the suns energy is reflected back into space by clouds and dust or absorbed by the atmosphere
- not all wavelengths of light can be absorbed and used for photosynthesis
- light may not fall on a chlorophyll molecule
Why is less that 20% of a producer/consumers NPP used by the next consumer in growth?
- some of the organism is not consumed
- some pairs are fibrous
- some energy is lost in excretory materials
- some is lost as heat from respiration to the environment
