crashMATHS
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Hey,

I've posted a few resources on the other thread, but, over time, they have become scattered almost everywhere and are becoming difficult for people to find. So, as requested, here's a thread with them attached.

I will continue to update this thread from now with the questions I make for each topic. Some of the files are attached to the thread itself, others are given by links to my site, simply because they are too large to upload otherwise.

Hope you all find them useful!

F214 Paper:
http://crashmaths.com/wp-content/upl...14-Paper-1.pdf
Mark Scheme attached.

Kidney Questions Attached
Answers (this is ignoring alternatives etc):
Spoiler:
Show


Anything underlined is needed in its entirety, semi-colons separate marking points and where commas are used within a marking point, this indicates that information on either side of the comma is necessary to score the marking point

1(a) renal artery ; unfiltered; 69000 (anything between 66000-72000 should be fine); ultrafiltration;

(b) any three from:
occurs in proximal convoluted tubule;
sodium ions are actively pumped out of the (PCT) cells, into the tissue fluid;
(specialised) co-transporter proteins move glucose / amino acids into the cells lining the PCT, with sodium ions, from the PCT;
water moves into the cells lining the PCT, by osmosis;
QWC: one mark for spelling and using three of these words correctly: osmosis, proximal convoluted tubule, cells, tissue fluid, actively, ions, co-transporter proteins, glucose, amino acids.

(c) proteins / polypeptides (note: amino acids will not be credited);

(d) B; idea that purple colour indicates presence of proteins; idea that while C has a little protein, B has too much; description of potential issue with the nephron, i.e. basement membrane damaged etc;

(e) diffusion; idea that dialysis fluid contains the optimum / correct concentrations of TWO named molecules (i.e. salts, urea, etc); partially permeable membrane; TWO named waste products removed. (Note: references to heparin and more specific dialysis methods will be ignored, as the question asks for the 'general' method)

(f) diet should be balanced; (in particular) enough protein; (must be monitored) to avoid waste products from accumulating between dialysis treatments; avoid malnutrition; avoid obesity.

2 (a) Award at most one HA, HD, PA, PD mark.

HA1: no need for operation;
HA2: idea that don't need to undergo dialysis every day;
HA3: Joshua can learn to do it himself at home;

HD1: strong restrictions on diet;
HD2: idea that Joshua cannot be not mobile while doing it;
HD3: takes a lot of time;

PA1: little equipment required;
PA2: no need to visit dialysis clinics;
PA3: can be mobile;

PD1: most be carried out every day;
PD2: operation necessary;
PD3: idea that Joshua may not like the idea of a tube being inside his abdomen;

(b) any two from:
gas chromatography / mass spectrometry;
urine sample used to form chromatogram;
compared with standard chromatograms;
QWC: one mark for any of the following two words spelt and used correctly: chromatography, spectrometry, chromatogram, standard

3 (a) homeostasis is the maintenance of a constant internal environment; despite changes;
when water potential of the blood decreases/increases, it is detected by the hypothalamus;
more / less ADH is released when the water potential of the blood decreases / increases;
negative feedback;

(b) ADH is secreted by action potentials that travel down neurosecretory cells;
DPH inhibits the opening of voltage-gated sodium channels (to prevent epileptic shocks);
(hence) idea that action potentials down neurosecretory cells are inhibited;
less ADH is secreted;
on a warm day, too much water will be lost / not enough reabsorbed (ora);

(c) can advise patients who take DPH to monitor their water intake OR reference to improved scientific database; patients who suffer from ADH overstimulation can take DPH to counteract this (owtte).


Cloning Questions Attached
Answers (this is ignoring alternatives etc):

Spoiler:
Show


Anything underlined is needed in its entirety, semi-colons separate marking points and where commas are used within a marking point, this indicates that information on either side of the comma is necessary to score the marking point.

1(a) (a clone is) a cell/tissue/organism that is genetically identical to another cell/tissue/organism;; (2nd mark for 'genetically')
clones are derived from the same DNA;
clones can be natural/artificial;
named example, i.e. Dolly the sheep;

(b) award at max 3 A marks and 3 D marks:

A1: advantageous alleles can be selected;
A2: (all clones are) genetically identical;
A3: idea that slow breeding organisms can be made to reproduce quickly;
A4: specific example, i.e. totipotent stem cells can be used for organ replacement;
A5: specific example, i.e. in tissue culture, plants can be made to reproduce very quickly;
A6: specific example, i.e. in vegetative propagation in Elm trees, trees can survive disease;

D1: no genetic variety;
D2: clones are more susceptible to extinction during disease outbreaks (owtte);
D3: reduces biodiversity;
D4: accept qualified ethical argument if linked to specific example, i.e. cloning humans reduces individuality etc;
D5: specific example, i.e. during organ replacement, organs can be rejected;
D6: specific example;

QWC: at least one mark scored from A4-6 and D4-6

2(a) vegetative propagation;

(b) mitosis;
produced from one organism / two organisms not involved (accept higher level responses that outline the mechanism in Elms);

(c) elm produces root suckers / basal sprouts;
grow from meristematic tissue;
root suckers grow from the ground;
mitosis;
happens (usually) when tree trunk is damaged;

(d) Credit any two valid examples: disease, burning, felling, etc;;

(e) Award at max 2 A and 2 D marks:

A1: allows the Elm to spread;
A2: root suckers contain the same genetic material as the parent Elm;
A3: root suckers bypass the dorment seedling phase and mature quicker;
A4: quicker than producing seeds;

D1: no genetic variation;
D2: root suckers are often short lived;
D3: more susceptible to disease;
D4: no new varieties can be formed;

Note: no genetic variation so more susceptible to disease scores 2 instantly (mp D1 and D3)

3(a) choose the hybrid potatoes that are most resistant to the fungi;
put these hybrid potatoes under stress (if examples given, must be 2) / use of an auxin inhibitor;
so that they produce root suckers;
these root suckers are clones of the hybrid potatoes (and so are resistant to the fungi too);
repeat this process over many generations;

(b) resistant gene isolated;
reverse transcriptase used (to synthesise complementary DNA strand);
insertion of gene into potato cell; IGNORE references to plasmids, restriction enzymes, etc
suitable method to check to see which hybrid varieties have taken up the gene;
repeat over many generations;
aseptic technique;

OR

artificial selection;
isolate resistant potato plant;
breed resistant potato plant with other potato plants;
idea that caution must be taken to prevent inbreeding;
suitable method to check which offspring are resistant;
using the resistant offspring, repeat this over many generations;

4(a) small piece of plant tissue taken / explant, from shoot tip / other named meristematic region;
idea that at different stages, different nutrient growth medium are used;
acclimatisation;
it can produce large quantities of a plant species quickly;
only small amount of plant material required;

(b) natural vegetative propagation involves use of plant organs other than the seed and spore; accept 2 named examples, i.e. tubers / suckers / slips / etc;
idea that artificial vegetative propagation is based on the existence of totipotency (owtte);
accept 2 named examples of tissues manipulated in artificial vegetative propagation, i.e. root / stem / shoot tip / meristematic tissue / etc;
one mark for named species for natural vegetative propagation that is used to explain a key feature of it;
if no marks, award 1 mark for the basic idea that artificial vegetative propagation involves human input, whereas natural vegetative propagation does not.

(c) Two As and Ds

A1: farmers know exactly what crop plant will be produced;
A2: advantageous alleles can be selected;
A3: large output from small input;
A4: requires little space;
A5: costs reduced for farmers (or explanation);
A6: AVP;

D1: all plants are susceptible to environmental change (accept named example in replacement, i.e. disease);
D2: genetic diversity reduced / gene pool smaller / owtte;
D3: reduced biodiversity
D4: no meiosis, so there is no new combinations of traits;
D5: AVP

5 (a) stem cell is an undifferentiated cell;
that has the capability of turning into / differentiating into other cells;
by turning on/off genes;

(b) named example, i.e. organ replacement;
described use, i.e. totipotent stem cells (from individual / donor) can be made to turn into the required organ (owtte);
benefit, i.e. less chance of rejection / reduces the strain on donor lists;

(c) A;
genetic material comes from sheep A;
If states B, apply CON and award no marks.

(d) egg cells may contain genetically different DNA to (somatic cells in) sheep A; due to crossing over in meiosis / accept other higher level reasons;
enucleated cell contains cell cytoplasm that is necessary to support growth;
contains organelles / nutrients (accept named examples);
AVP (you can check with me, there are many higher level responses, but to think of and list them all would take awhile...)


Genetic Profiling Questions
Link here: http://crashmaths.com/wp-content/upl...NG-F215-QS.pdf
Answers (this is ignoring alternatives etc.):
Spoiler:
Show


Anything underlined is needed in its entirety, semi-colons separate marking points and where commas are used within a marking point, this indicates that information on either side of the comma is necessary to score the marking point.

1 (a) double helix;
four named bases (ignore A T C G, must be named);
adenine pairs with thymine AND cytosine pairs with guanine;
sugar-phosphate backbone;
negatively charged;

(b) (i) genomes are sheared into smaller fragments (owtte);
named advantage, i.e. easier / quicker to sequence (ignore references to it being cheaper);

(ii) allow for many copies of the genome to be made; quickly;
allows scientists to have more genetic material to experiment with (or similar);

(iii) DNA extracted from BACs, using (different) restriction enzymes;
DNA fragments separated (by size), using electrophoresis;
automated gene sequencing / description;
overlapping fragments analysed;

(c) knowledge can be shared;
experiments / tasks / projects can be distributed between different scientists;
experiments / tasks / projects can be completed quickly;
results can be checked / repeats done easily;
AVP;

(d) allows evolutionary relationships to be studied / phylogeny of humans;
modelling the effects of changes to DNA can be carried out (owtte);
to identify genes that are responsible for named condition, i.e. disease, cancer, obesity, diabetes, etc;
DNA between humans / other species can be compared;
allows information about the relative importance of genes to life to be collected (owtte);
may be useful in the future;
may reveal new information about human genetics;

2(a) (i) Right to left;

(ii) DNA is negatively charged / attracted to anode / positive electrode / DNA has excess phosphoryl groups;

(b) use of agarose gel;
use of restriction enzymes to cut DNA samples into fragments;
DNA sample are placed in wells; near the cathode / negative end of the gel;
use of electric current; for (about) two hours (accept +/- 1 hour);
shorter lengths of DNA move faster than longer lengths of DNA through the gel;
use of dye; to see the position of fragments / bandings;
QWC: at least 5 of the mps given in the order of the scheme

3(a) compare with group B;
to see if the drug is effective;

(b) use of a stain / dye;

(c) yes;
bandings have shifted;
protein has become smaller;

(d) use of a DNA probe that is complementary to the section of DNA in question (owtte);
probe labelled with radioactive marker that can be detected by use of photographic film OR fluorescent marker that can be detected by use of UV light;
probe will anneal to DNA section; (by) complementary base pairing;

4(a) amplifying / amplification / accept conjugates;

(b) At max four marks from S and four marks from D

similarities

S1: DNA polymerase;
S2: adenine pairs with thymine and guanine pairs with cytosine;
S3: DNA nucleotides are added to one strand;
S4: nucleotides added in the 5’ to 3’ direction;
S5: double-stranded DNA molecule produced;
S6: AVP;

differences (accept ora throughout)

D1: PCR requires a primer;
D2: PCR involves a cycle of heating and cooling;
D3: PCR can only replicate short sequences of DNA;
D4: PCR does not use helicase;
D5: PCR must be done many times / DNA replication copies the whole genome once;
D6: AVP

(c) 10

(d) suspect 2;
bandings between suspect 2 and the murder weapon most closely linked (owtte);
unlikely to be suspect 3 because common bandings are also common suspect 1 (so it is likely to be common in all humans) (owtte);
NOTE: wrong suspect scores 0/3

(e) represent genes / proteins that are common to life;
named fundamental protein (or gene for higher level answers) to humans, i.e. named enzymes for respiration, named hormones, etc;
individuals may be closely related;

5(a) DNA polymerase;
primers and free nucleotides, some of which are tagged with a fluorescent marker (owtte);
each nucleotide has a colour specific to a nitrogenous base;
primer anneals to genome, by complementary base pairing;
idea that no more nucleotides are added when one tagged with fluorescent marker is attached;
laser reads colour sequence;

(b) quicker;
idea that no need for manual work;
greater database has been accumulated;
allow one advantage of more data, i.e. more detail on phylogeny between organisms can be deduced;


Photosynthesis Questions
Link here: http://crashmaths.com/wp-content/upl...IS-F214-QS.pdf
Insert: http://crashmaths.com/wp-content/upl...214-INSERT.pdf
Note: Figure 2.1 is immensely small because I just didn't have time to play around with photoshop and make it fit, so when answering the question, you may want to look at the insert to see the enlarged, intended version of it. Question 3 is also incorrectly labelled, it should be part (a), then (b), (c) and (d), rather than (f), (g) and (h). Apologies!
Answers (this is ignoring alternatives etc.):

Spoiler:
Show


Anything underlined is needed in its entirety, semi-colons separate marking points and where commas are used within a marking point, this indicates that information on either side of the comma is necessary to score the marking point.

1(a) organelles;
any named photosynthetic pigment, i.e. chlorophyll(a/b), xanthophyll, carotene;
chemical;
photolysis;

(b) flow through ATP synthase;
facilitated diffusion;
down electrochemical gradient;
(this) synthesises ATP;

(c) it reduces NADP, by adding electrons to it;

(d) idea that as electrons move down ETC, energy is released;
energy used, by coenzymes, to actively pump H+ ions, from stroma to thylakoid space;; (one mark for coenzymes, one mark for energy being used to pump H+ into thylakoid space)

(e) N; N; B; B;

2(a) an autotroph uses light / chemical energy to synthesise complex, organic molecules, from inorganic molecules (owtte);

heterotrophs ingest and digest complex organic molecules, to release the chemical potential energy stored within them;

(b) 5-10 um (accept any number between this interval or a range with end points in the interval +/-2 um)

(c) intermembrane space AND stroma;

(d) folded to create large surface area;
membrane-bound proteins;
example of named membrane-bound protein AND function;
surrounded by stroma; so products from LDR that are needed for calvin cycle / LIDR can easily pass into the stroma;

(e) (i) only contain photosystem I;
they only need to undergo cyclic photophosphorylation;

(ii) to actively transport potassium ions / minerals into the cell;
to lower the water potential of the cell;
cause water to enter the guard cell by osmosis;
causing the opening of the stomata;
accept ORA throughout

3 (a) amino acids used to build proteins; named example of plant protein;
fatty acids combine with glycerol to produce lipids; lipids can be used for cell membranes / to form liposomes / named function / insulation;
named hexose sugar, i.e. glucose / sucrose;
glucose can be used in respiration / sucrose can be used as additional energy source / stated use of hexose sugar in plants;
recycled NADP can be used to transport more H+ ions to the Calvin cycle / light independent reactions;
QWC: any three words spelt and used correctly from: glucose, respiration, energy, sucrose, ions, active (transport), protein(s), membrane(s)

(b / labelled ‘f’) idea that light independent reactions suggest that the reactions can happen in the absence of light, which isn’t true;

(c / labelled ‘g’) idea that curves upwards, reaches a maximum and curves back downwards; ACCEPT (tilted) parabolic;

(d / labelled ‘h’) initially, temperature is a limiting factor;
enzyme activity in light independent reactions is low;
at peak, temperature is no longer a limiting factor OR at peak, light intensity / CO2 concentration is now a limiting factor;
as temperature increases, the oxygenase activity of rubisco increases / rubisco fixes less CO2 in replace of O2;
at very high temperatures, proteins involved in photosynthesis are likely to denature / become damaged;

4(a) 0.0076; 0.010; 0.016;

(b) as light intensity increases, the time taken for disc to rise increases;
use of data WITH UNITS to support this claim;
this is because light intensity is a limiting factor; which reduces the rate of photosynthesis because less electrons are excited; leading to less reduced NADP;
photosynthesis rate begins to slow down OR reference to difference in the rate of photosynthesis between 200 and 400 lux is greater than the difference in the rate of photosynthesis between 400 and 600 lux;
this is because light intensity is no longer limiting OR temperature / CO2 is now a limiting factor;

(c) they discs sink because the sodium hydrogencarbonate solution makes them denser than water;
oxygen produced in photosynthesis replaces sodium hydrocarbonate solution in air gaps / spongyy mesophyll layer;
this reduces their density, causing the discs to rise;

(d) she is incorrect (no mark) BECAUSE replicates make data more reliable, not accurate; (answer must dismiss the accuracy issue and state the data is made more reliable to be awarded the marking point)



Respiration Questions
Link here: http://crashmaths.com/wp-content/upl...ON-F214-QS.pdf
Insert: http://crashmaths.com/wp-content/upl...6/06/graph.pdf
Answers (this is ignoring alternatives etc.):

Spoiler:
Show


Anything underlined is needed in its entirety, semi-colons separate marking points and where commas are used within a marking point, this indicates that information on either side of the comma is necessary to score the marking point.

1(a) all organism require energy;
for named process;

(b) ATP; hexose/fructose-1,6-bisphosphate;
left and right hand side are symmetrical and are as such:
reduced NAD / NADH;
reduced NAD/ NADH;
pyruvate;

1 mark for first two compounds; 1 mark for the reduced NADs; 1 mark for pyruvate;

(c) reduced NAD travels to inner membrane;
(first) electron carrier accepts electrons from it;
electrons pass down ETC and are accepted by oxygen;
energy released used to pump H+ ions from matrix to inter membrane space;
H+ ions flow through ATPsynthase, generating ATP

(d) idea that to prevent glucose from leaving the cell;

(e) simple organisms all had a cytoplasm;
cells initially only used glycolysis;
more complex organisms developed membrane-bound organelles; and began to perform the subsequent reactions in (aerobic) respiration;
Accept higher references to the theory of endosymbiosis.

2(a) ribose, adenine and three phosphates appearing in some form;
correctly joined together;

(b) it is found in all cells;
it releases energy in small manageable packets;
all cells have enzymes that can synthesise ATP
AVP;

(c) This question is per unit glucose (it should really say, if you’ve done it otherwise and got correct multiples still give the marks as it’s my bad)

(i) 2 (net) / 4;

(ii) 2;

(iii) 30 +/- 2

(iv) 0

(d / labelled ‘f’) some ATP used to actively transport / shuttle pyruvate into mitochondria;
some energy from ETC is lost as heat / not used to pump H+ ions into intermembrane space;
H+ ions may leak through outer membrane and thus not flow through ATP synthase;
not all NADH feeds into the ETC;

3) accept protons instead of H+ ions throughout

NADH offloads electrons to first electron carrier;
electrons pass down electron transport chain; releasing energy;
energy used to pump H+ ions from the matrix into the intermembrane space;
H+ ions accumulate in the intermembrane space;
proton motive force / electrochemical gradient;
H+ ions diffuse / move back into the matrix through ATPsynthase; by facilitated diffusion;
this drives the synthesis of ATP from ADP and an organic phosphate;
AVP;
Any three technical words spelt and used correctly

4) (a) chemiosmosis is the diffusion of H+ ions / protons;
through ATPsynthase;
down an electrochemical gradient / proton motive force;
to drive the synthesis of ATP;

(b) idea that is the osmosis because it is H+ ions and the ‘chemi’ prefix refers to it being down a chemical gradient

(c) proton motive force refers to the electrochemical gradient created by the pumping of H+ ions into the intermembrane space;;

(d) for each of this, mark using the idea that

A – many organelles have an inner and outer membrane, yet not experience chemiosmosis, so this is not evidence;
B – this suggests the accumulation of H+ ions in the intermembrane space, so is evidence;
C – channel proteins do not necessarily mean ATP is produced by the flow of H+ ions, so is not strong evidence;
D – this is evidence because it suggests that ATPsynthesis is dependent on the electrochemical gradient, as the theory suggests;

(e) experiments need to be designed;
results need to be validated;

5 (a) Definitely not 6 marks! Should only be 4!

Lactate;
CO2 / carbon dioxide;
Ethanal;
Ethanol;


(b) only glycolysis / substrate level phosphorylation occurs;
only 2 ATP produced net;
idea that krebs cycle / ETC / other reactions cannot occur;
oxygen not available as final electron acceptor;

(c) lactate itself is not ‘toxic’ in the presence of buffers;
lactate only has negative effects if it causes a change in pH;

(d) anaerobic respiration allows the yeast cells to grow initially;
colony reaches maximum size and then falls;
initially anaerobic respiration provides the yeast with energy; to grow / for named cellular process;
anaerobic respiration in yeast produces ethanol;
when ethanol concentration rises, it becomes toxic; causing yeast cells to die;

6(a) a respiratory substrate is an organic substance that can be used for respiration;; (one mark for organic)

(b) 8%;;
one mark for (17-15.8)/15.8 or an answer that is not the nearest whole number

(c) (2870/30.6) *0.32 = 30 mol ATP approx.

one mark for correct working, one mark for the answer being clearly shown

(d) some substrates have more hydrogen atoms; which can be used to produce ATP in the ETC;

(e) glucose was the most common carbohydrate in the early stages of evolution (owtte);
so glycolytic enzymes became abundant by natural selection;



Brain/Muscles/Sliding Filament Questions
Link here: http://crashmaths.com/wp-content/upl...ES-F215-QS.pdf
Insert: http://crashmaths.com/wp-content/upl...NSERT-F215.pdf
Answers will be uploaded tomorrow

Ecology / Module 3 Questions
Link here: http://crashmaths.com/wp-content/upl...GY-F215-QS.pdf
Insert: http://crashmaths.com/wp-content/upl...215-INSERT.pdf
Answers will be uploaded tomorrow

Here are also some links to other sites that I think may be useful:

F214 Resource Bank - http://www.physicsandmathstutor.com/...on/ocr-unit-4/
F215 Resource Bank - http://www.physicsandmathstutor.com/...on/ocr-unit-5/
Notes - http://www.thebiotutor.com/a2-notes1.html

Attached files
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dpoojaraa
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Thanks for this! Really appreciate everything you do
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Superbubbles
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thank yo for making this thread! is the F214 paper predictions or just a normal paper that has been put together?
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crashMATHS
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(Original post by Superbubbles)
thank yo for making this thread! is the F214 paper predictions or just a normal paper that has been put together?
I made the questions up for practice. It's not necessarily a prediction, but I think other topics will probably make an appearance, but it's just extra practice.
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gabby07
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Your questions are ace!! Super useful, so thanks . Are you planning on doing a series at all on the Ecosystems and Sustainability topic in the textbook?
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simba and mufasa
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Thanks for this, realy appreciated
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crashMATHS
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(Original post by gabby07)
Your questions are ace!! Super useful, so thanks . Are you planning on doing a series at all on the Ecosystems and Sustainability topic in the textbook?
Doing photosynthesis right now, I will do that after - I need to go over it myself too!
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AqsaMx
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(Original post by kingaaran)
I made the questions up for practice. It's not necessarily a prediction, but I think other topics will probably make an appearance, but it's just extra practice.
Just wondering, but will you be doing anymore questions for F214?
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AqsaMx
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(Original post by kingaaran)
Doing photosynthesis right now, I will do that after - I need to go over it myself too!
Would you also mind explaining the first MS point for 'explain the purpose of the enucleated ovum' ?
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simbbo
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Hey kingaaran I also find your questions really useful! Would you be able to do some questions on peripheral/autonomic nervous system (pg230-1) the various different types of muscle structures (pg234-5), and the interlink between the muscles, nerves and hormones (pg 238-9)?. There was a hard question (q2 of the jan 2011 f215 I think) which merged all of these topics, and since there aren't that many past paper questions on it, I was wondering if you would be able to write any? Not so much on the sliding filament model as I know there are loads of questions available on this online, and the concept is pretty repetitive.

Thank youu
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spiritless98
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Thank you!!


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smozsolution
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Hey man, brilliant resources!

They're really helping me consolidate my knowledge and practice applying ideas which I need. Any thoughts for some questions on meiosis and genetic problems (epistasis, genetic crosses etc)?

Thanks!
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crashMATHS
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(Original post by smozsolution)
Hey man, brilliant resources!

They're really helping me consolidate my knowledge and practice applying ideas which I need. Any thoughts for some questions on meiosis and genetic problems (epistasis, genetic crosses etc)?

Thanks!
Sure, will add that to the list Yours should be done by Thursday-ish
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smozsolution
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(Original post by kingaaran)
Sure, will add that to the list Yours should be done by Thursday-ish
That's brilliant, thank you very much
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crashMATHS
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(Original post by AqsaMx)
Would you also mind explaining the first MS point for 'explain the purpose of the enucleated ovum' ?
Gametes are produced by meoisis and so they will vary in their genetic makeup to somatic cells because meiosis does not produce genetically identical cells.

If we want to clone an animal, it is best that we do not take an egg cell from that animal because this will not be the same as the animal we want to clone. Instead, we take a somatic cell from them, an egg cell from another variety of the animal, and combine them, so that we have both the DNA we want and the right cellular conditions for growth.
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username2097061
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(Original post by kingaaran)
X
Thank you very much!

Could you please explain whether plant roots undergo negative phototropism, as it makes sense it terms of the direction of their growth, but also is rather contradictory as roots cannot directly respond to light intensity, as they're not exposed to it (underground)?

Likewise, can you say plant shoots exert negative geotropism?
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simbbo
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(Original post by kingaaran)
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Hey man, any chance you have the genetic profiling answers? If not you haven't finished them yet, no worries.
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crashMATHS
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(Original post by simbbo)
Hey man, any chance you have the genetic profiling answers? If not you haven't finished them yet, no worries.
(Original post by mil88)
Thank you very much!

Could you please explain whether plant roots undergo negative phototropism, as it makes sense it terms of the direction of their growth, but also is rather contradictory as roots cannot directly respond to light intensity, as they're not exposed to it (underground)?

Likewise, can you say plant shoots exert negative geotropism?
Hey , sorry to both of you, I have an exam tomorrow, so I will be updating this with lots of new stuff I've made and answering the qs tomorrow.
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yoda123
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Kingaaran you are a god
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Genetic profiling answers added. Photosynthesis worksheet should be added today or tomorrow
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