AS Biology P1 MCQs Preparation Thread

[shivana]

Can anyone help me with this question 39 from 07 nov.
anyone Please explain!!!!!

the answer is supposed to be B

MY EXAM IS IN ONE HOUR PLEASE HELLLLLLP!!!!

 

[rogue94]

Can anyone help me with this question 39 from 07 nov.
anyone View attachment 12969 Please explain!!!!!

the answer is supposed to be B

MY EXAM IS IN ONE HOUR PLEASE HELLLLLLP!!!!

Due to increased amounts of dust, less sunlight reaches producers. Due to insufficient sunlight, the producers die. As the populations of producers decreases, the populations of the consumers will also decrease (food chain). As there are more dead organisms, there will be more decomposers (more proteins converted to ammonia) and hence, more nitrifying bacteria (which convert ammonia to nitrates). Hence, the correct option is B.

 

[shivana]

Due to increased amounts of dust, less sunlight reaches producers. Due to insufficient sunlight, the producers die. As the populations of producers decreases, the populations of the consumers will also decrease (food chain). As there are more dead organisms, there will be more decomposers (more proteins converted to ammonia) and hence, more nitrifying bacteria (which convert ammonia to nitrates). Hence, the correct option is B.

THANKYOU SOOOO MUCH FOR THIS SIMPLE INTELLIGENT EXPLANATION!!!!!!!!!
I get it know thankssss!!
GODBLESS

 

[Jaf]

Sorry i didnt thank you before! BUT better late than never haha anyways THANKS

Don't worry! In fact, there is no need to thank me.

 

[hela]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s10_qp_11.pdf Q2 Q11 Q30 Q39
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s10_ms_11.pdf Q2 C 11 A 39 C 30 D

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s06_qp_1.pdf Q12 D Q13 A Q22 C Q26 D
http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s06_ms_1.pdf

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w06_qp_1.pdf Q13 C
http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w06_ms_1.pdf

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s05_qp_1.pdf Q38 A

 

[rehmanmunir]

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s04_qp_1.pdf
can any one tell me q7, 14 , 24

 

[fishcook]

Q7 Turgid plant tissue is placed in a solution which has the same solute potential as the contents of
the cells. The diagram shows a cell after one hour.
Which equation describes the value of the pressure potential for this cell?
A pressure potential = solute potential of the cell
B pressure potential = solute potential of the external solution
C pressure potential = water potential of the cell
D pressure potential = zero

why is the answer D? its from winter 03

 

[Marwa Ezzat]

Guys can anybody explain to me the answer of Question no.7 june 2004 ?

 

[hela]

ON 2004 Q 16B Q38 D Q29B Q30A
http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w04_qp_1.pdf
ON 2003 Q7D http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w03_qp_1.pdf

 

[fishcook]

Q13 How does increasing substrate concentration affect the rate of an enzyme-catalysed reaction in
the presence of a competitive inhibitor?
A) The rate of the reaction decreases.
B) The rate of the reaction decreases initially and then recovers.
C) The rate of the reaction increases.
D) The rate of the reaction is not affected.

why is the answer C? please help

 

[Aries_95]

Can anyone please explain this one point?
I read in a book that the plasmodium which causes Malaria can pass form the mother to the fetus via the placenta. But in one question, the mark scheme said that malaria cannot pass directly from parents to child?
9700/11/M/J11 Q. 36.
Help me please!

 

[ahmed abdulla]

just tell me the way ...

 

[Sarah_3420]

what are the most important topics to study for paper 1? any help please?

 

[Gimmick]

Can anyone please explain this one point?
I read in a book that the plasmodium which causes Malaria can pass form the mother to the fetus via the placenta. But in one question, the mark scheme said that malaria cannot pass directly from parents to child?
9700/11/M/J11 Q. 36.
Help me please!

fetus is not the same as the child.

 

[Gimmick]

just tell me the way ...

magnification = observed size (ruler) / (divide) actual size
they should be in the same units (i.e metres)
magnification = 2500
therefore

2500 = observed size / actual size
substitute to get the actual size (as = observed / 2500), and then multiply that by 1 um (micrometre)

 

[Aries_95]

fetus is not the same as the child.

Excuse me?

 

[Gimmick]

Excuse me?

The fetus is the unborn child, but a child is ... the born child?
I think they mean "child" as in the disease can pass through breastfeeding and not through the placenta...however I think the answer is b) malaria not because it's "correct" but because of elimination, i.e the other answers are incorrect. Also, they say "parent", not "mother", so sickle-cell is obv. incorrect as it require both parents to have the gene for sickle-cell..

Sickle cell anemia - genetic / hereditary and so can be passed from parent to child
TB / Cholera - bacterium and so can be transferred through the placenta? Not sure.

 

[ahmed abdulla]

nice expaination

 

[Aries_95]

The fetus is the unborn child, but a child is ... the born child?
I think they mean "child" as in the disease can pass through breastfeeding and not through the placenta...however I think the answer is b) malaria not because it's "correct" but because of elimination, i.e the other answers are incorrect. Also, they say "parent", not "mother", so sickle-cell is obv. incorrect as it require both parents to have the gene for sickle-cell..

Sickle cell anemia - genetic / hereditary and so can be passed from parent to child
TB / Cholera - bacterium and so can be transferred through the placenta? Not sure.

When the child is born, it may have the plasmodium inside it, hence suffer from malaria. Sickle cell anemia is an inherited disease and definitely cannot be the answer.
THIS IS A DAMN CONFUSING QUESTION...I mean Malaria can pass from the parents to child....URGH!!!

 

[Aries_95]

The fetus is the unborn child, but a child is ... the born child?
I think they mean "child" as in the disease can pass through breastfeeding and not through the placenta...however I think the answer is b) malaria not because it's "correct" but because of elimination, i.e the other answers are incorrect. Also, they say "parent", not "mother", so sickle-cell is obv. incorrect as it require both parents to have the gene for sickle-cell..

Sickle cell anemia - genetic / hereditary and so can be passed from parent to child
TB / Cholera - bacterium and so can be transferred through the placenta? Not sure.

AND...if they are asking whether the disease can pass through breastfeeding, what about TB and cholera? I mean bacteria cannot pass through breast feeding!!!