key terms Flashcards
cellular respiration
process by which food is broken down to yield ATP which is used as source for energy for metabolic reactions
respiratory substrate
substance oxidised during cellular respiration
aerobic respiration
form of cellular respiration that takes place in mitochondria in presence of oxygen
stalked particles
structures where ATP production takes place on inner mitochondrial membrane
reduction
addition of electrons to substance by addition of hydrogen or removal of oxygen
oxidation
removal of electrons from substance by addition of oxygen of removal of hydrogen
hydrogen acceptor
molecule which receives hydrogen and becomes reduced in cell biochemistry
NAD
coenzyme that acts as a hydrogen acceptor
reduced NAD
NAD which has accepted a hydrogen atom in metabolic pathway
FAD
hydrogen carrier and coenzyme
-in cellular respiration it accepts hydrogen to form reduced FADH2
driving production of ATP
respirometer
piece of apparatus used for measuring rate of respiration in whole organisms or cultures of cells
glycolysis
first stage of cellular respiration which takes place in cytoplasm and common in aerobic and anaerobic respiration
pyruvate
end product of glycolysis
glycerate 2-phosphate
GP phosphorylated 3C intermediate in process of glycolysis
ethanol
organic chemical with formula C2H5OH produced as result of anaerobic respiration in fungi and some plant cells
lactate
3C is end product of anaerobic respiration in mammals
anaerobic respiration
form of cellular respiration that takes place in cytoplasm where no oxygen present
krebs cycle
series of biochemical steps that lead to complete oxidation of glucose resulting in production of carbon dioxide, water and large amounts of ATP
link reaction
reaction needed to move products of glycolysis into krebs cycle
Acetyl coenzyme A (acetyl CoA)
2C compound produced in link reaction which feeds directly into krebs cycle combining 4C to form 6C
decarboxylases
enzymes that remove carbon dioxide
dehydrogenases
enzymes that remove hydrogen ( carry out oxidation reactions)
oxidative phosphorylation
oxygen dependent process in electron transport chain where ADP phosphorylated
electron transport chain
series of electron carrying compounds along which electrons transferred in series of oxidation reduction reactions producing ATP
chemiosmosis
process that links electrons that are passed down electron transport chain and production of ATP by movement of hydrogen ions through membrane along electrochemical, pH and conc gradients
cytochromes
members of electron transport chain
-protein pigments with iron group like haemoglobin reduced by electrons from reduced FAD which is reoxidised with production of a molecule of ATP
cytochrome oxidase
enzyme in electron transport chain which receives electrons from cytochromes and is reduced as cytochromes are oxidised with production of 1 ATP
chemiosmotic theory
developed by peter mitchell- explains production of ATP in mitochondria chloroplasts and elsewhere in living cells
autotrophic
organisms that make complex organic compounds from simple compounds in their enviroment
photosynthesis
process by which living organisms- plant and algae capture energy for the sun using chlorophyll and use it to convert carbon dioxide and water into simple sugars
heterotrophic
organisms obtain complex organic molecules by feeding on other living organisms or their dead remains
envelope
of a chloroplast is outer and inner membranes along with the intermembrane space
grana
stacks of thylakoid membranes within a chloroplast
thylakoid
membrane disc found in the grana of a chloroplast
lamellae
extensions of the thylakoid membranes which connect two or more grana acting as supporting skeleton in the chloroplast, maintaining a working distance between the grana so they get max light and function as possible
stroma
matrix which surrounds the grana and contains the enzymes needed to complete the process of photosynthesis and produce glucose
chlorophyll a
blue green photosynthetic pigment found in all green plants
chlorophyll b
yellow green photosynthetic pigment
carotenoids
photosynthetic pigments made up of orange carotene and yellow xanthophyll
phaeophytin
grey pigment which is breakdown product of other photosynthetic pigment
absorption spectrum
graph of amount of light absorbed by pigment against the wavelength of light
action spectrum
graph demonstrating the rate of photosynthesis against the wavelength of light
photosystem
combination of chlorophyll pigments which absorbs light of wavelength 700nm and is involved in cyclic and non cyclic photophosphorylation
photosystem 2
combination of chlorphyll pigments which absorbs light wavelength 680 nm and is only involved in non cyclic phosphorylation
light dependent reactions
reactions that take place in light on thylakoid membranes of chloroplasts
-they product ATP and split water molecules in photochemical reaction providing hydrogen ions to reduce carbon dioxide and produce carbs
light independent reactions
reactions that use reduced NADP and ATP produced by the light dependent stage- the calvin cycle
calvin cycle
takes place in the stroma of the chloroplast and result in the reduction of carbon dioxide from the air to bring about the synthesis of carbs
photochemical reaction
reaction initiated by light
cyclic photophosphorylation
process that drives production of ATP
-light excited electrons from PS1 taken up by electron acceptor and passed directly along electrons transport chain to produce ATP with electron returning to PS1
non cyclic photophosphorylation
process involving both PS1 and PS2 in which water molecules are split using light energy to provide reducing power to make carbs and produce more ATP
calvin cycle
series of enzyme controlled reactions that take place in the stroma of chloroplast and result in reduction of carbon dioxide from air to bring about synthesis of carbs
photolysis
splitting of molecule using light
ribulose bisphosphate
5C that joins with co2 from air in calvin cycle to fix the co2 to form a 6C compound
RUBISCO
ribulose bisphosphate carboxylase/oxygenase
-rate controlling enzyme that catalyses reaction between co2 and RuBP
glyceraldehyde 3-phosphate- GALP
3C produced in calvin cycle using reduced NADP and ATP from in light dependent stage
-GALP used to replace RuBP needed in first step of the cycle in glycolysis and the krebs cycle and synthesis of amino acids
photorespiration
alternative reacction catalysed by RUBISCO in low co2 area which used O2 and releases co2 making photosynthesis less efficient
gluconeogenesis
synthesis of glucose from non carbs
limiting factor
factor needed for a reaction such as photosynthesis to progress that is closest to its minimum value