Ocr Gateway Additional Science C3 B3 P3 15th june Unofficial Markscheme

The 6 marker was like why does the pug have breathing problems

I know - but i have no ideo how to answer it

I put mitosis and for the first question I didn't round the number up and for the breathing problem one I said a reduction in gene pool or something and diseases are passed on if one organism has it

Wasn't it meiosis?

Anyone got an unofficial mark scheme?

For the stairs question about calculating work done did anyone get 300j?

I thought it's mitosis BC it asked about sperm cells and not gametes ?


Posted from TSR Mobile

gametes are just another word for sperm and egg. Mitosis is to do with asexual reproduction which is why the answer wasn't mitosis as sperms are part of sexual reproduction.

but wasn't the question something like how do sperms cell divide?? I presumed cells in a body divided by mitosis but ugh I read it wrong loool it was worded strangely


Posted from TSR Mobile

i will try to make a mark scheme - help would be appreciated

Respiration (6)
Heart rate equation - 86.4 {2
B) he is above the training zone / is training anaerobically / will not get maximum benefit / less efficient way of respiring. 2
C) Gives you more hawmoglobin / this transports energy / bind with it in lungs / breaks down for musles / can respire for longer / get more from it. 2

Pugs (8)
6 marker - not too sure really
B) meiosis 1
C) diploid 1

This was either bio or chem
Dna stuff (9)
match up - cant remeber order but c-g a-t 2
Cant remember the 3 names 2
C) lock and key diagram / only fits on shape in / specific will not work otherwise 2
D) different amino acids mean diff shape / change active site / not do job properly 2
E) will have no effect bc it still creates the same amino acid 1

Soldiers
Not sure what came up in this quesion

Drugs (9)
Drugs = batch because only small amounts needed & they are very specific 1/2
Expensive - equipment costs / labour costs / patent costs / marketing / research 2
Pick the best & work out percentage yield 6marker - yield = 60%. Best = D had high atom economy & percentage yield - give advantages of that. 6

Rate of reaction
Cant remember the rest of this qu
Rate is slower in cold bc less succesful collisions / enzymes slower / energy passed on slower 3
Limiting 1
Exothermic reaction - bond being made / heat given out / bonds between oxygen & magnesium 2/3

Speed time
6 marker - describe the graph & how to get distance (area under the graph)

Equation 300 3
This will be wrong bc steep steps / not taking into account direction etc 1
Cant remember what this part was either

Seat belts -
Should share ideas so others can build on them/ others can create new ideas / others can provide extra proof. 2
Can test seat belts - survey / crash test dummies / computer simulation 2
Material should be strong / stretchy etc & justify 2
Pregnant people - can harm baby / will save lives 2
Crumple zones ? Was there a question on thsi


Last question 5
Keep same mass 1
More fuel consumption so more co2 released 1
Another qu
No he isnt right bc the mass is doubled too / 8 times more kinetic energy not 4 (2)

ohhhh i see why you said that. Lool, never mind though. It was only worth one mark. I messed up on the amino acid question where they asked you to list the three proteins or something like that... I stupidly rearranged the order .... Don't ask me why.. then after the exam I realised that you were actually supposed to write the actual names of the proteins that were made -_- So annoyed. It seems so obvious but I managed to mess it up. No wonder they had that table with all the names of the proteins. -_- looool but oh wells