energy exchanges in and between organisms Flashcards
glycolysis is…
first stage in both aerobic and anaerobic respiration, occurs in the cytoplasm
net products of glycolysis are…
2 x ATP
2 x NADH
glycolysis: glucose splits into…
glucose phosphate, then hexose biophosphate, then into 2 triosephosphate molecules, then 2 pyruvate molecules
link reaction occurs in the…
mitochondria matrix
link reaction: pyruvate turns into…
acetate, then acetyl coenzyme A
link reaction: net products
2 x CO2
2 x NADH
link reaction: what is added to acetate to make it acetyl coenzyme A
coenzyme A
Krebs cycle basics…
occurs in mitochondrial matrix
pyruvate enters matrix by active transport
link reaction converts pyruvate to acetyl coenzyme A
Anaerobic respiration…
NADH is re-oxidised so it can re-enter glycolysis
Krebs cycle: acetyl coenzyme is converted into…
6C compound, 5C compound, 4C compound, then back into coenzyme A to be used at start if the reaction again
Krebs cycle: net products…
6 x NADH
2 x ATP
2 x FADH
4 x CO2
lipids and amino acids that can be used instead of glucose process…
lipids hydrolysed to glycerol + fatty acids
glycerol phosphorylated into triose phosphate + enters Krebs cycle
amino acid hydrolysed + amino acid group removed
carbon compound left Krebs cycle
oxidative phosphorylation process…
electrons and protons (H+) are reduced from reduced coenzymes
NADH–> e- + H+ + NAD
FADH –> e- + H+ + FAD
electrons flow along e.t.c in series of redox reactions
electrons release energy, which is used to join ADP + Pi –> ATP
oxygen is the final electron acceptor, combines with electrons and protons to form water
oxidative phosphorylation makes most ATP in aerobic respiration.
what is an ecosystem…
form of biological community containing all living + non-living factors
flow of energy through ecosystems
some organisms obtain energy from the sun or consuming organisms
energy used to synthesise organic compounds
most sugars synthesised by plants respiratory substrates, rest used to from biological molecules (forms biomass of the plants)
how is biomass measured….
in terms of mass of carbon or dry mass of tissue per given area
chemical energy store in dry biomass can be measured using colorimetry