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OCR Biology A Exam Thread (Breadth - May 26, 2016 and Depth - June 7, 2016)

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For the cell cycle, i got mitosis, meiosis, mitosis, meiosis, mitosis (so alternating) but the n and 2n were so confusing, i essentially ignored them and just went by the textboxes

Reply 1361

asinghj

Original post by Logic4Life

I put about the 30-35 repeat too. Then i said use a mean

I wrote use ranges of temperature between 30 and 35

Reply 1362

Jitesh

The question about agar, did you write it was extracellular?

Reply 1363

username1631419

Original post by asinghj

I wrote that as well :.(

why would that be wrong?

Reply 1364

Logic4Life

Original post by MilindS99

For the cell cycle, i got mitosis, meiosis, mitosis, meiosis, mitosis (so alternating) but the n and 2n were so confusing, i essentially ignored them and just went by the textboxes

The letter pointing to sperm and egg was meiosis right? The spores was mitosis

Reply 1365

DaVinciGirl

Original post by asinghj

I wrote use ranges of temperature between 30 and 35

I wrote that and also wrote that to go to in 10 second intervals

Posted from TSR Mobile

Reply 1366

Ozil5

Original post by sdeponte

what did people put for why the student t test wasn't suitable? I had no clue

Made up some bs about how t test should be used to measure between two means and this one was categoric data so couldn't be used. I had no idea lol

Reply 1367

Logic4Life

The mitosis one about why it was in G1 for the full time, i put it was a stem cell that was still growing and undifferentiated

I got like 30/70 lol

Original post by Ozil5

Made up some bs about how t test should be used to measure between two means and this one was categoric data so couldn't be used. I had no idea lol

Yeah that should be right :smile:

Reply 1370

DoubleDoors

Original post by OddFuturez

I don't think your supposed to say why it's less efficient but why it suits the mammal/frog

No, the question asked you to evaluate two things: the circulation; the relative efficiencies.

Reply 1371

bhavik-

Original post by asinghj

I wrote use ranges of temperature between 30 and 35

I said this.

(edited 7 years ago)

Reply 1372

aliyah99

But I thought it could be in G0 as well because it was G0/G1 so I put it was a specialised cell or a senescent cell?

Reply 1373

Desouza123

For the Q about Chitin and the difference I wrote monosaccharides are made of only C,H and O but the structure shown has Nitrogen.
The one following that about the sugar I put: Hexose sugar made from Beta glucose (no idea lol)
For the structure i wrote about: Glycosidic bonds, Condensation reaction releasing h20. Forms straight chains like cellulose, H bonding etc.

Reply 1374

ronnydandam

Original post by brodingoson

alright salt machine

Reply 1375

OddFuturez

Original post by DoubleDoors

No, the question asked you to evaluate two things: the circulation; the relative efficiencies.

Yea sure m8

Reply 1376

Hogthoughts

Original post by brownlands

Unfortunately every phi test has an expected value and a real value - the two tissues were the expected and real values. If it was 2, every phi test would have 1 as their degree of freedom. That's why it's 3 and not 1.

Ahhh I see

Reply 1377

haes

I did not like that paper! Too many suggest questions :/

Anyway my answers were:
Immediately after expiration was A
Mitosis, meiosis, mitosis;;;; meiosis, meiosis
13.835(?) for chi squared and 3 for the degrees of freedom (i cant believe it came up when everyone was literally just talking about if it's in the spec or not) and my explanation was that there is a significant difference between observed and expected.

Chitin? Said it keeps the trachea open and provides support and prevents collapsing. And i totally guessed the one after but i said less air will get to the tracheoles and therefore cells so less respiration for those cells?

Use a pH meter for a less subjective method of measuring ph (idk if this is correct no one seems to have put the same) and to do the experiment between 25-35 (although 30-35 makes more sense) with smaller intervals.

3140% in the last percentage question