Flashcards
Biology Unit 4: Respiration and Photosynthesis
Cards in this deck (53)
- 1Define energy:The ability to do work
- 2Why are the units of energy?Joules, J
- 3What does the body need energy for?Metabolism
Movement
Active transport
Maintenance, repair, division
Production of substances (enzymes etc.)
Maintainance of body themperature - 4How does energy flow through living systems?Light energy converted by plants to chemical energy (glucose) by photosynthesis
Chemical energy is converted into ATP during respiration
ATP used to do work - 5Word equation for then hydrolysis of ATPAdenine triphosphate + water =
Andenine disphosphate + inorganic phosphate (+ energy) - 6Decribe how ATP is converted into ADP and ADP is converted into ATPATP is hydrolysed into ADP and inorganic phosphate, the ADP is then condensened (phosphorylated) into ATP
- 7Name the three types of phosphorylationPhotophosphorylation
Oxidative phosphorylation
Substrate level phosphorylation - 8How are leaves adapted for photosynthesisLarge surface area
Thin (short diffusion pathway)
Transparent cuticle
Long upper mesophyll with lots of chloroplasts
Stomta (gas exchange)
Xylem (transport water to leaf) - 9General equation for photosynthesis6carbon dioxide + 6water =
Glucose + 6oxygen - 10How are the chloroplasts structured?Grana = stacks of discs called thylakoids, connecting tubular extensions = lamellae.
Stroma = fluid filled matrix, contain starch grains - 11What occurs when chlorophyll absorb light?Elections are excited to higher energy level, these electrons leave the molecule and are taken up by an electron carrier
- 12When the chlorophyll loses electrons is it oxidised or reduced?Oxidised
- 13How does the excitation of chlorophyll lead to ATP production?Electrons pass along a number of electron carriers, in a series or redox reactions, each carrier is at a lower energy level so the electrons lose energy at each stage this energy is used to synthesis ATP
- 14How is reduced NADP produced in the light dependent reaction?The photolysis of water produces the electrons needed to replace those lost in the chlorophyll, this also produces hydrogen ions which reduce NADP
- 15Equation for the photolysis of water:2Water (+light) =
4Hydrogen ions + 4Electrons + Oxygen - 16Why is the photolysis of water needed during the light dependant reaction?To produce the electrons needed to replace those lost by the chlorophyll, also produces hydrogen ions to reduce NADP and oxygen
- 17Where does the light dependant reaction take place?Grana/Thylakoids of the chloroplasts
- 18How are the thylakoids adapted for their function (light dependant reaction)?Large surface area - for the attachment of chlorophyll, electron carriers and enzymes.
Network of proteins, to hold chlorophyll in a way to maximise light absorption.
Granal membranes contain enzymes for ATP synthesis.
DNA and ribosomes - so chloroplasts can manufacture proteins needed - 19How does carbon dioxide enter the chloroplast?Through the stomata of the leaf then into the stroma the chloroplast
- 20How is carbon dioxide used to produce organic molecules (glucose) and regereratec RuBP in the calvin cycleCarbon dioxide combines with a 5 carbon compound called RuBP producing two 3 carbon molecules; ATP and reduced NADP are used to produce GP and TP; NADP is reformed and returns to the light dependent reaction; some TP is converted to organic substances most is regenerated RuBP using ATP
- 21Where does the light independent reaction take place?In the stroma of the chloroplast
- 22Why does the light independent reaction not take place in the absence of light?The light independent reaction uses the products of the light dependent reaction
- 23What is the law of limiting factors?At any given moment the rate of a physiological process is limited by the factor that is at its least favourable value
- 24What are two ways of measuring the rate of photosynthesis?Measuring the volume of oxygen released by the plant;
Or the volume of carbon dioxide taken up by the plant - 25If light intensity is the limiting factor how is it related to the rate of photosynthesis?Rate of photosynthesis is directly proportional to intensity of light
- 26What is the compensation point?The point where the volume of oxygen produced and volume of carbon dioxide used by the plant is exactly balanced;
no net production or loss of gas - 27How does carbon dioxide concentration affect the rate of photosynthesis?Carbon dioxide concentration affects the enzyme activity thus increasing rate of photosynthesis
- 28How does temperature affect the rate of photosynthesis?Plants have an optimum temperature above this rate will decrease as the enzymes will become denatured
- 29How and why is glucose phosphorylated?Glucose is phosphorylated to make it more reactive the phosphate comes from the hydrolysis of ATP
- 30How does phosphorylated glucose two molecules of pyruvate?Phosphorylated glucose is split into two 3 carbon molecules of triose phosphate; the 2 triose phosphate molecules are oxidised; hydrogen ions are removed and transferred to a hydrogen ion carrier NAD; enzymes convert triose phosphate pyruvate producing 2 atp molecules
- 31How are two molecules of reduced NAD produced?Two molecules of triose phosphate are oxidised producing two hydrogen ions which can reduce two molecules NAD
- 32Why is the overall ATP yield of glycolysis only two?Two molecules of ATP are required to phosphorylate glucose, only four molecules of ATP are produced when two molecules of triose phosphate are converted into two molecules of pyruvate
- 33Where does glycolysis take place?In the cytoplasm of the cell
- 34Why is glycolysis the only source of ATP in the absence of oxygen (anaerobic conditions)?Glycolysis does not require oxygen to occur whilst all the other stages of respiration do require oxygen
- 35Give the equation for the link reactionPyruvate + NAD + coenzyme A =
acetyl coenzyme A + reduced NAD + carbon dioxide - 36Explain how the link reaction produces 2 molecules of carbon dioxideFirst pyruvate is oxidised; two hydrogen ions are accepted by NAD; the resulting acetyl group combines with coenzyme a to produce acetyl coenzyme a; and one carbon dioxide molecule
- 37How does the krebs cycle produce two reduced hydrogen carriers and ATP?Acetyl coenzyme a combines with a four carbon molecule to produce a 6 carbon molecule; this 6 carbon molecule loses carbon dioxide and hydrogen to give the 4 carbon molecule these hydrogen ions are used to produce reduced hydrogen carriers, ATP is formed by substrate level phosphorylation
- 38what is the overall yield for the link reaction and krebs cycle for one molecule of glucosetwo reduced NAD molecules, two reduced FAD molecules, two ATP molecules and 6 carbon dioxide molecules
- 39explain the significance of the krebs cyclebreaks down macromolecules into smaller ones produces hydrogen ions letter carried to the electron transport chain by oxidative phosphorylation leading to ATP production regenerate the 4 carbon molecule that combines with acetyl coenzyme a and isa source of intermediate compounds used by cells in the manufacture of other substances
- 40why are hydrogen acceptors oxidised where do the protons and electronshydrogen atoms are released from the hydrogen carriers the atom split in two protons and electrons the electrons move along the electron transport chain
- 41how is the energy lost at each electron acceptor usedTo pump electrons from the matrix intuothe inter membrane space
- 42how is an electrochemical gradient establishedthe concentration of protons in the intermembrane space is higher in the matrix
- 43how does protons moving back into the matrix produce atpprotons move down at the electrochemical gradient back into the matrix via atp synthase this drive theory synthesis of atp from adp and inorganic phosphate
- 44what is the name of the process which generates atpchemo osmosis
- 45how is water produced in the electron transport chainin a matrix at the end of the electron transport chain the protons and electrons and oxygen combine to form water
- 46why is oxygen described as the final proton accepter in the electron transport chainoxygen combines with the protons to form water
- 47what process can occur in anaerobic conditionsglycolysis
- 48what is the equation for anaerobic respiration in plants and some microbe?Pyruvate + reduced NAD = ethanol + carbon dioxide + NAD
- 49how is ethanol produced from pyruvate in plants and some microbesPyruvate loses carbon dioxide and accepts hydrogen from reduced NAD to produce ethanol
- 50What is the equation for anaerobic respiration in animals?Pyruvate + reduced NAD = lactate + NAD
- 51How is lactate produced from pyruvate in animals?Pyruvate takes up two hydrogen atoms from the reduced NAD forming lactate
- 52Why is lactate build up bad in humans?Lactate is harmful,causes muscle cramps and fatigue
- 53What is the energy yield from aerobic respiration?Two molecules of ATP from every one molecule of glucose
Information
- Description
- AQA A2 Biology Photosythesis, Respiration and ATP (chapter 2, 3 and 4)
- Created by
- Deleted user · Jan 2017
- Updated
- Jan 4, 2017
- Views
- 48
- Tags
- History
-
- Created by Charlotte Lloyd · Mar 8, 2015
- Copied by victoria sayer · Jan 3, 2017
- Rating