Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 357127 times)

Offline 8T

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3060 on: June 07, 2010, 03:27:03 pm »
Hello again.
O/n 03 Link :http://www.freeexampapers.us/IGCSE/Biology/CIE/2003%20Nov/0610_w03_qp_1.pdf
No. 15 I dont get how water diffuses?I thought water molecules move by osmosis so any help?
 Ans: B
Know how to ask. There is nothing more difficult for some people, nor for others, easier.

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3061 on: June 07, 2010, 03:34:43 pm »
Hello again.
O/n 03 Link :http://www.freeexampapers.us/IGCSE/Biology/CIE/2003%20Nov/0610_w03_qp_1.pdf
No. 15 I dont get how water diffuses?I thought water molecules move by osmosis so any help?
 Ans: B

Water evaporates from the mesophyll cells surfaces then diffuses, as vapor, through the intercellular spaces before leaving the leaf through the stomata during TRANSPIRATION. So basically the water first evaporates and then in those spaces u see in the diagram in tht Q well it stays there as water vapor. and when the stomata opens, these water vapors diffuse out through the open stomata.   :) hope you got me. :) so yeah the ans is B.
;D

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3062 on: June 07, 2010, 03:36:16 pm »
Hello again.
O/n 03 Link :http://www.freeexampapers.us/IGCSE/Biology/CIE/2003%20Nov/0610_w03_qp_1.pdf
No. 15 I dont get how water diffuses?I thought water molecules move by osmosis so any help?
 Ans: B

Water in liq. state move by osmosis, here its evaporates from the spongy mesophyll cells. Water is in gas state (vapor) and all gases diffuse, hence diffusion

Offline mdwael

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3063 on: June 07, 2010, 03:41:29 pm »
Hey guys please help me I want the answers for 1994-2001  paper 1 bio its there in freeexampapers but its not opening can someone just go there and download it and send it to me on email mdwael@live.com the link is

http://www.freeexampapers.us/IGCSE/Biology/CIE/1993%20-%202003/Answers%20June%201993%20--%202003%20P1,%203,%20&%206.pdf

I will never forget this favour..Its my last exam tommorow, I want it to pass in peace
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Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3064 on: June 07, 2010, 03:41:49 pm »
The surface waters of the ocean contain a population of microscopic plants (plankton).
Which factor would result in fewer of these plants?


A an increase in the population of microscopic animals
B greater concentration of mineral nutrients
C more light
D warmer ocean water

What's the answer and WHY?


Lol, easy.. ;D its A as microscopic animals will eat these plants.. they get reduced in numbers. :) the other three options will only benefit the plant see? :)
;D

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3065 on: June 07, 2010, 03:43:00 pm »
The surface waters of the ocean contain a population of microscopic plants (plankton).
Which factor would result in fewer of these plants?


A an increase in the population of microscopic animals
B greater concentration of mineral nutrients
C more light
D warmer ocean water

What's the answer and WHY?


A, right? Predators.

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3066 on: June 07, 2010, 03:45:53 pm »
Trickyy.. :/ Please help  :)

Is it B?
;D

Offline zarkajordan

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3067 on: June 07, 2010, 03:51:12 pm »
The activity of decomposers returns substances to the atmosphere.
Which products of decomposition enter the atmosphere?
A carbon dioxide and nitrogen
B carbon dioxide and water
C oxygen and nitrogen
D oxygen and water

The marking scheme says the answer is B how come its not A?

Offline mdwael

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3068 on: June 07, 2010, 03:53:37 pm »
The activity of decomposers returns substances to the atmosphere.
Which products of decomposition enter the atmosphere?
A carbon dioxide and nitrogen
B carbon dioxide and water
C oxygen and nitrogen
D oxygen and water

The marking scheme says the answer is B how come its not A?

products of respiration are CO2 and water, I dont see why nitrogen is produced
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Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3069 on: June 07, 2010, 03:55:13 pm »
Trickyy.. :/ Please help  :)

Is it B?

We got the same thinking. I really don't know y. I just guessed it because for these kinda ques. the answer is always awkward, you know what I mean. Which year? What is it given in the ms?

Offline ksitna

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3070 on: June 07, 2010, 03:56:05 pm »
yeah @ raywin i think it is B too
take whatever you want and give nothing back :)

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3071 on: June 07, 2010, 03:56:28 pm »
The activity of decomposers returns substances to the atmosphere.
Which products of decomposition enter the atmosphere?
A carbon dioxide and nitrogen
B carbon dioxide and water
C oxygen and nitrogen
D oxygen and water

The marking scheme says the answer is B how come its not A?

Nitrogen are only released into the atmosphere by bacteria, NOT decomposers.
;D

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3072 on: June 07, 2010, 03:58:40 pm »
We got the same thinking. I really don't know y. I just guessed it because for these kinda ques. the answer is always awkward, you know what I mean. Which year? What is it given in the ms?

I found these hard Qs posted by some guy on SF.. :S i tried them out, prolly some REALY OLD PAPERS. there was NO ms.. :|
;D

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3073 on: June 07, 2010, 04:00:52 pm »
More Tricky :'(
;D

Offline Raywin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3074 on: June 07, 2010, 04:03:08 pm »
;D