respiration and photosynthesis Flashcards
define photosynthesis
is a reaction using light energy to produce glucose
requires water and carbon dioxide to form glucose and oxygen
what are the four stages photosynthesis occurs
photolysis
photo ionisation
chemiosmosis
production of ATP and reduced NADP
what is photolysis
the splitting of a molecule of water in the presence of light.
occurs in the light dependent reaction
how are the products of photolysis used
the hydrogen ions are picked up by NADP to from reduced NADP
the electron is used in electron transport chain
oxygen is used for respiration
describe the photoionisation of chlorophyll
light energy is absorbed by the photosystem ,where the energy causes the electrons to be excited
energy released is used to make ATP and reduced NADP in chemiosmosis
describe chemiosmosis
electrons when they gain energy they move past electron transport chain on thylakoid membrane
when the electrons move down the chain they release energy used to pump the proton pump
where it is actively transported from stroma to thylakoid
producing electrochemical graident
how is ATP formed and NADP formed
hydrogen ions move down from thylakoid space into the stroma
using ATP synthase by facilitated diffusion
this ATP synthase
catalyses the phopsphorylation of ADP into ATP
how is NADPH formed
NADP combines with hydrogen to form NADPH
which is final electron acceptor
where does the calvin cycle occur
in the stroma
what catalyses the whole reaction
Rubisco found in the stroma
what are the first part of the calvin cycle
carbon dioxide reacts with RUBP (a 5 carbon molecule)
catalysed by rubisco
to produce 2 molecules of glycerate 3 phosphate
describe the formation of TP
GP picks up hydrogen from NADPH which goes onto reform NADP
GP is reduced into TP
using energy from ATP
how is RUBP regenerated
One Carbon is removed from of of the TP molecules
leaving with five carbons
then the second ATP is used to regenerate RUBP
how many times does calvin cycle occur
it happens six times where in total 6 carbons are removed
what are the three limiting factors in photosynthesis
light intensity
CO2 concentration
temperature
what does RUBP stand for
ribulose bisphosphate
what are agriculture practices to overcome limiting factors
artificial lighting
artificial heating
addition of CO2 by burinng fuels
outline a method for extracting pigment from leaf
use a pestel or motar to extract part of the leaf
using extraction solvent propanone
use capillary tube to spot the pigment on the pencil line
what are the four main stages of respiration
1.glycolysis
2.link reaction
3.krebs cycle
4.oxidative phosphorylation
outline the stages of glycolysis
glucose is phosphorylates into glucose phosphate
then glucose phosphate is split into triose phosphate
triose phosphate oxidised into pyruvate
whilst TP is oxidised NAD picks up H ion to form NADH
and also forms ATP
how does pyruvate and NADH move out the cytoplasm
active transort
where does glycolysis occur
in the cytoplasm
where does the link reaction occur
in the mitchondrial matrix
outline the stages of the link reaction
- pyruvate is oxidised
per pyruvate molecule net gain of CO2 - in this reaction NAD is reduced to form NADH
3.acetate combines with co enzyme A to produce acetyl co enzyme
what are the products of glycolysis
2x pyruvate
2x NADH
2x ATP
what are the products of the link reaction
2x acetyl co enzyem A
2X CO2
2x NADH
outline stages of the krebs cycle
acetyl coenzyme enters kreb cycle and then reacts with 4 carbon molecule
this then forms a six carbon molecule
2 carbon dioxide removed
then co enzyme FADH removed and NADH
series of redox reactions occur using energy from ATP
what are the total products of krebs cycle
4 xCO2
2 xATP
2 xFADH
6 xNADH
what happens in the electron transfer chain
the reduced co enzyme produced from the krebs cycle release their hydrogens
hydrogen split into protons and electrons
,those electrons move down electron transport chain
how does the proton gradient occur
energy released from the electron transport chain is used to actively transport proton pump of Hydrogen ions
from mitchondrial matrix to the intermembrane space
how is ATP produced
the hydrogen ions move down concentration gradient from intermembrane space into the mitchondrial membrane using ATP synthase
this casuse ADP to be phophorylated into ATP
catalyses the formation of ATP
how is water formed
electrons from the elctron transport chain is picked up by oxygen along with hydrogen ion
what is the role of water
it is the final electron acceptor
describe anaerobic respiration
it is respiration in the absence of water
describe anaerobic respiration in animals
pyruvate is reduced to form lactate
reduced by NADH
NAD is used again in glycolysis
where does lactate go agter produced in anaerobic respiration
goes to the liver
describe anaerobic respiration in plants
pyruvate is decarboxylated to form ethanal
ethanal is reduced to ethanol using NADH
what are the advantages of the products of respiration
they convert NADH into NAD for glycolysis
what are the disadvatages of producing Lactate
acidic so decreases PH
causes muslce fatigue
what is the disadvantage of producing ethanol
when ethanol conc is above 12% they die
ethanol dissolves cell membranes
how is respiration measured
using a respirometer
what is the purpose of sodium hydroxide in a respirometer
Absorbs CO2 so there is a decrease in pressure
as O2 is consumed
