OCR Gateway GCSE Biology B B4 B5 B6 (12th June 2015)

The atria contract question was:
0.64/8= 0.08

It was one circle, divided into 8 segments. Everyone got thrown off by the fact that there was an outer circle, but they were counted in the same segments. The entire cycle is divided into 8. One beat is 0.64. Therefore, divide 0.64 by 8.

B1, B2, B3 exam was a little easier for me, but both exams were good overall. The 6 mark questions for this exam were brilliant, even better than the B1, B2, B3 exam. I got an A* for both Biology mocks, and I found the real exams to be much better than the mocks, so hoping for an A*.

I'm just glad Biology is over. I cannot wait for chemistry. We have our stimulus for the chemistry control assessment already, and it's looking good.

Reply 64

Original post by HarrisonGCSE

I swear it was 6.04 x 1/8. I thought the two circles were separate and not added together. Did they mention the two circles were together and i just missed it?

Yup got 0.08 I think I assumed they were and for the 6 marker I got 1.42

Where you guys getting 1.5...

(edited 8 years ago)

Reply 65

haes

6

what was the answer to why you could not see the bacteria colonies?

Reply 66

xxNerdyBirdyxx

Original post by lasertown

The atria contract question was:
0.64/8= 0.08

It was one circle, divided into 8 segments. Everyone got thrown off by the fact that there was an outer circle, but they were counted in the same segments. The entire cycle is divided into 8. One beat is 0.64. Therefore, divide 0.64 by 8.

B1, B2, B3 exam was a little easier for me, but both exams were good overall. The 6 mark questions for this exam were brilliant, even better than the B1, B2, B3 exam. I got an A* for both Biology mocks, and I found the real exams to be much better than the mocks, so hoping for an A*.

I'm just glad Biology is over. I cannot wait for chemistry. We have our stimulus for the chemistry control assessment already, and it's looking good.

The outer circle made a huge difference; it separated the impulses in the ventricles from that in the atria. If you consider that fact then there are 16 individual segements to consider. 0.64/16 = 0.04s
If you counted 8 segments then you have mistakingly counted the impulse in the ventricle and atria as one.

Reply 67

Mudas

13

For the algal bloom question (Kinda), what did you say was the pollutant? I said a Nitrogenous Fertiliser?

Reply 68

iliam

5

For the 6 marker I got 1.6 as the index, 1.57 rounded up so I'm hoping there will be a range from 1.5-1.6, what do you guys think?

Reply 69

They're entirely separate outer parts are irrelevant did you actually read the question?

Reply 70

xxNerdyBirdyxx

Original post by iliam

For the 6 marker I got 1.6 as the index, 1.57 rounded up so I'm hoping there will be a range from 1.5-1.6, what do you guys think?

I wouldn't worry if I was you - it's likely to be a range. Most of my friends rounded, but I got 1.51 (2dp).

Reply 71

lasertown

Original post by DaringDaniel

Yup got 0.08 I think I assumed they were and for the 6 marker I got 1.42

Where you guys getting 1.5...

Cross-sectional area of artery while relaxed was given, 11.5.
Area of a circle: pi r(squared) Pi: 3.14

r was given, 2

3.14 x 2 squared = 12.56

(12.56-11.5)/0.7 = 1.51428 . . .

1 d.p. = 1.5

Some people got 1.6, as they rounded up the 12.56 when working out the area. I only round up at the end, it gives a more accurate result. So I don't know which will get the mark. 1.5 is more mathematically correct, however. The mark scheme may allow a range of results, e.g. 1.5-1.6.

How did you get 1.42?

Reply 72

12.5-11/0.7 or 7 can't remember was it not?

Reply 73

xxNerdierBirdxx

Original post by xxNerdyBirdyxx

The outer circle made a huge difference; it separated the impulses in the ventricles from that in the atria. If you consider that fact then there are 16 individual segemeynts to consider. 0.64/16 = 0.04s
If you counted 8 segments then you have mistakingly counted the impulse in the ventricle and atria as one.

Yes, but if that were the case, then how would we know what the atria were doing in the first 8 segments, and the ventricles were doing in the second 8 sections? This is a measure of time not impulses.

Reply 74

shredder457

3

I put for the heater question that he needed to consider energy costs as higher temperatures require more energy which costs more.
Also, for the index one I thought it was 1.56 which rounds up to 1.6, but I expect that getting the correct index is only one mark as long as you get that it falls into both the healthy and unhealthy groups.
The B1, B2, B3 exam went really well for me and in this one although I know that I lost at least 3 marks, I knew the rest. However, there's just something about that exam that makes me feel really like I didn't do very well, even though I have no idea why I feel that way :-P
I think I lost marks because I put LH as the hormone that controls bone length (which I know is wrong but had to guess), and I put that gastric juice had no enzymes in (which is wrong because bile has no enzymes in - I checked when I got home). That means that the error could have possibly been carried forwards to part 2 but I hope that I worded part 2 in a way that wouldn't lose me any more marks.
Overall, it went well but I just have a bad feeling about it...

Reply 75

Mudas

13

Original post by iliam

For the 6 marker I got 1.6 as the index, 1.57 rounded up so I'm hoping there will be a range from 1.5-1.6, what do you guys think?

It was 1.52 im afraid :P
Pie X 2sq = 12.56637061
12.56637061-11.5
DIVIDED BY
0.7
=
1.523386592

Reply 76

Original post by lasertown

Cross-sectional area of artery while relaxed was given, 11.5.
Area of a circle: pi r(squared) Pi: 3.14

r was given, 2

3.14 x 2 squared = 12.56

(12.56-11.5)/0.7 = 1.51428 . . .

1 d.p. = 1.5

Some people got 1.6, as they rounded up the 12.56 when working out the area. I only round up at the end, it gives a more accurate result. So I don't know which will get the mark. 1.5 is more mathematically correct, however. The mark scheme may allow a range of results, e.g. 1.5-1.6.

How did you get 1.42?

I rounded down...

Reply 77

ladysophie