** 2013 Biology HL Before/After **

HugsiePie

RML wrote: »

Give the role of the enzyme RNA polymerase.

Joins mRNA to the DNA strand??

Hold on, DNA Polymearase or RNA Polymerase?!

ahmdoda

RML wrote: »

Give the role of the enzyme RNA polymerase.

Joins mRNA to the DNA strand??

yea man what the he** is this! never heard of this enzyme any where so i asummed their talking about mRNA

pajero12

Am i right in saying for the cell division question where 2n=6, you put 6 pairs of chromosomes down the equator of the cell?

Lucan Bohs

(iii) Do you think that population graphs for a host species and its main parasite would show
similar fluctuations? Explain your answer.


I said no because the parasite will decrease in numbers if there's a decrease in its host!?

RML

HugsiePie wrote: »

Hold on, DNA Polymearase or RNA Polymerase?!

It was RNA polymerase.

RML

pajero12 wrote: »

Am i right in saying for the cell division question where 2n=6, you put 6 pairs of chromosomes down the equator of the cell?

I had 3 pairs..

HugsiePie

RML wrote: »

Give the role of the enzyme RNA polymerase.

Joins mRNA to the DNA strand??

According to wikipedia RNAP is necessary for constructing RNA chains using DNA genes as templates, a process called transcription.

kevin12345

Lucan Bohs wrote: »

(iii) Do you think that population graphs for a host species and its main parasite would show
similar fluctuations? Explain your answer.


I said no because the parasite will decrease in numbers if there's a decrease in its host!?

I said no because the parasite replicates in its hundreds in its host, then the host is destroyed = Huge number of parasites??
I didn't say it exactly like that but along those lines.

HugsiePie

RML wrote: »

It was RNA polymerase.

Well feck.

ConorIsCool18

It was a disaster for me, I said a had the ecto/endotherm thing right then mixed them about like a idiot as i doubted myself! why couldn't they just make a normal paper? next it will be project biology

Jordan537

i assumed that over time parasites could lead to the hosts death, i put yes. My reason being that because the parasite death was a slow one then the host could have time to reproduce.

Lucan Bohs

kevin12345 wrote: »

I said no because the parasite replicates in its hundreds in its host, then the host is destroyed = Huge number of parasites??
I didn't say it exactly like that but along those lines.

I think it's another ambiguous Q tbh

valencianista

What did people draw on Q8 for the graphs of the heat denaturation experiment? I dont remember doing any graphs for that experiment only one for effect of pH on enzmyme activity and another for effect of temperature of enzyme activity.

HugsiePie

Jordan537 wrote: »

i assumed that over time parasites could lead to the hosts death, i put yes. My reason being that because the parasite death was a slow one then the host could have time to reproduce.

MWA HAHAHA

shawki

RML wrote: »

I had 3 pairs..

Can't find a definite answer for this anywhere online Was it 3 or 6 pairs?

Lucan Bohs

On the ecology;

(ii) Outline two biological similarities between the nitrogen cycle and the carbon cycle.
(iii) Suggest why continual monitoring of the environment is valuable.

HugsiePie

shawki wrote: »

Can't find a definite answer for this anywhere online Was it 3 or 6 pairs?

I was talking to a bio teacher last night and asked him the same question.
You should've had 6 chromosomes, 6 X shapes, 12 spindle fibres so I guess 3 pairs.

woopah92

woopah92 wrote: »

I couldn't decide of they were looking for glucose or a pyruvate molecule for the first one :pac:

And the other one is sodium/calcium alginate

I wrote sodium alginate and calcium chloride and wrote that I felt the question was very unclear.

valencianista

HugsiePie wrote: »

I was talking to a bio teacher last night and asked him the same question.
You should've had 6 chromosomes, 6 X shapes, 12 spindle fibres so I guess 3 pairs.

In my text book theres diagrams with examples of diploid cells. The one that says 2n=6 has 3 pairs (so 3 X shapes)

11Charlie11

I wrote glucose and sodium alginate
Anyone have any idea how many marks would be going for the question on how endospores form? I got that wrong

internet_user

11Charlie11 wrote: »

I wrote glucose and sodium alginate
Anyone have any idea how many marks would be going for the question on how endospores form? I got that wrong

how do they from on bacteria? i think i wrote about a fungus for that

pajero12

valencianista wrote: »

In my text book theres diagrams with examples of diploid cells. The one that says 2n=6 has 3 pairs (so 3 X shapes)

But is the cell dividing in that diagram?

am23843

So disgusted by that 'bitty' paper. Asking awkward questions on different sections of the book. There was absolutely no rhythm or relevance between questions. The whole thing was just off putting and ambiguously worded. Not one person in my year felt confident about that paper which is truly shocking as we have some seriously intelligent students in our year. Worked my ass off all year studying biology only to be presented with the most experimental paper they've issued in the past 10 years. I needed that A1 for my course and now i'll be ecstatic with a B2. So disappointed, really feel like they screwed us on this one..
Have to say that i'm glad other people agree, if there's a public outcry about this paper surely something will be done so justice is served in the marking scheme. Wishing everyone the best hope we all get the grades we worked for

aimzLc2

I actually thought that was a lovely paper, could have been alot worse, some nice questions, few were a bit weird but i think if you studied you wouldn't have been too shocked for the majority

RML

I have to say our mock paper looked nicer than the actual exam!

ray2012

I have to say I liked the experiments (for the most part) and maybe 3 out of the 4 long questions I attempted were ok. The photosynthesis/respiration question was a dream :P

EvM

Think I did well over all, although one thing I know I ****ed up on is the cell division question where for some reason I thought it said draw a diagram of the telaphase stage and did that instead.. Oh well, at most it'll only be about 10 marks or so, and I got most of everything else. So happy that and geography are over and done with!

Monsieur Folie

It was a bit iffy alright and I'm worried I didn't perform at my best, but it was not half as bad as people are making it out to be. Apart from the odd vague question we haven't too much to be complaining about, and anything that was vaguely worded will be accounted for in the marking scheme. There's no need for public outcry. :P

Slow Show

shawki wrote: »

Can't find a definite answer for this anywhere online Was it 3 or 6 pairs?

My teacher told me once that both were acceptable and no one seems to be very sure here!

WigglinJelly

horrible horrible paper.. I thought there was a lot of repetition of types of questions? Especially around ecology and the environment/ evnvironmental issues etc?
Complete lack of plant biology and only reproduction and hormones for human biology? What?