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Molecules through adhesion full idea required h good

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molecules through adhesion; (full idearequired)h. good solvent of polar organic moleculesa.a. active transport of solutes from soil into roots;b. draws water by osmosisc. root hairs provide a large surface area for water uptake;d. carried through xylem vessels;e. transpiration is the loss of water (vapour) from leaves and stems / stomata;f. (transpiration) creates suction/pull/negative pressure;g. cellulose wall with rings of lignin give strength to resist (low) pressure;h. water pulled up due to capillary action/cohesion/adhesion;i. continuous column of molecules/transpiration stream;b.a. water only plays a role in non-cyclic photophosphorylation;b. chlorophyll absorbs light/photons and activates electrons of photosystem II;c. excited/active electrons of photosystem II are passed to carriers;d. photolysis is the splitting of water;e. produces O2and H+/proton and electrons;
f. O2released (as waste);g. electrons (from water) replace lost electrons in photosystem II;h. electrons from photosystem II pass (through carriers) to photosystem I;i. electrons from photosystem I pass to NADP+(in stroma);j. NADP+accepts H+/proton (from water) to form NADPH;k. electron flow causes protons pumped across thylakoid membranes/into thethylakoid space;l. creating a proton concentration gradient;m. chemiosmosiscouples electron transport to ATP synthesis;n. protons pass through ATP synthase/synthetase;o. NADPH/H+/proton is passed to the light-independent reactions (to fix carbon);c.Examiners reportThis was a popular question.7a, few completely related hydrogen bonding to surface tension. In discussingsolvent properties, a number neglected to draw in that water performed best atdissolving polar substances. When discussing adhesion, students should havereferenced the polarity of molecules.a.This was a popular question.In part b, many referenced the role of xylem. Many used terminology correctly in thissection making reference to transpiration pull, cohesion, adhesion and thetranspiration stream. The stages of water uptake that occur in the root was coveredin less detail and with less accuracy in general.b.This was a popular question.Part c was in general poorly done as the question required students to discuss therole of water. The details of photolysis were often excluded as were the correctdetails of chemiosmosis.c.Outline the metabolic processes that occur in starchy seeds during germination.[6]b.Explain the light-independent processes of photosynthesis in plants.
[8]c.MarkschemeRemember, up to TWO “quality of construction” marks per essay.a. water absorbed by the seed / seed rehydrated;b. water activates metabolism;c. gibberellin synthesized/produced/secreted;d. gibberellin stimulates the production of amylase;e. amylase digests/hydrolyses starch to maltose;f. maltose converted/hydrolysed to glucose (by maltase);g. glucose used in aerobic respiration;h. glucose used in synthesis/production of cellulose;b.

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Term
Summer
Professor
IBO
Tags
Photosynthesis, Plant Cell, phloem, Xylem

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