AS Biology P1 MCQs Preparation Thread

[Just M]

I bet tomorrow's paper is gonna be a killer. The trend has changed since S09. Just hope for there are more repetitions in the paper Anyways, all the best for tomorrow's candidate !!! Me as well

 

[Just M]

if this is helpful to u..please pray for me..thanx

Thx bro !!! All the best for tomorrow !!

 

[Soldier313]

Thx bro !!! All the best for tomorrow !!

u r welcome...thanx fr the wishes...need ur prayers and btw i am not a bro:/

 

[Just M]

u r welcome...thanx fr the wishes...need ur prayers and btw i am not a bro:/

Haha. Oooopss. Thanks Friend !!

 

[Soldier313]

Haha. Oooopss. Thanks Friend !!

lol, u r welcome

 

[Just M]

Hi. Need some help here Why is the answer for question 33 (paper 13,M/J/11) A not B ?? Oh btw, same year same paper question 40. Why is the ans C ??? Really don't understand.

 

[Soldier313]

Can someone please assist me with these 3 questions :

A.) When does the spiralisation and condensation of DNA take place??

B.) These are effects of emphysema, can someone please elaborate how exactly these effects come about?
1.surface area to volume ratio of lungs decreases
2.volume of oxygen diffused per unit time decreases

C.)
View attachment 12703

Thanx so much! God bless!

 

[Soldier313]

Hi. Need some help here Why is the answer for question 33 (paper 13,M/J/11) A not B ?? Oh btw, same year same paper question 40. Why is the ans C ??? Really don't understand.

Ans for 33 is A because saturated fats have no double bonds so their branches are straight and will fit together more closely unlike unsaturated which have double bonds.
qn 40 i don't know how to explain it

 

[thu]

Q6 from w10_12. Can anyone explain why ans is B please?

 

[Just M]

Can someone please assist me with these 3 questions :

A.) When does the spiralisation and condensation of DNA take place??

B.) These are effects of emphysema, can someone please elaborate how exactly these effects come about?
1.surface area to volume ratio of lungs decreases
2.volume of oxygen diffused per unit time decreases

C.)
View attachment 12703

Thanx so much! God bless!

Hi. As for part (A), are you talking about cell cycle ?? If its yes, i guess it happens during interphase. There are G1,S,G2. During S phase, this is where the DNA will replicate. Hope it helps.
For (B,1), the S.A.V ratio refers to the surface area of the alveolus. When there's emphysema, digestive enzyme elastase will be released by the phagocytes. This enzyme will break down the elastin wall of the alveoli, making it less elastic (permanently strecthed). As a result, all the alveoli will enlarge in their shape and thus, reducing the surface area.
(B,2), since S.A.V ratio decreases, this will delay the time for oxgen to diffuses.
For (C), i'm not very sure about this. Is the answer B ? Based on my opinion, peptide bond will form between amino acids (common). Since cystein also contain S, disulphide bridge will form too.

P/S: Plese correct me if I have made any mistakes in the explanations. Thanks

 

[Just M]

Q6 from w10_12. Can anyone explain why ans is B please?

Hi. The question stated only 1,4-glycosidic bonds are hydrolysed. So, only the left and right glucose are released from the molecule. Since 2 bonds are broken, two H2O molecule is needed. The middle glucose and the top glucose will remain attached as the bond joining them is 1,6-glycosidic bond. Hope it helps

 

[raamish]

in non-competitive inhibition does the inhibitor attack to the enzymes active site or does the inhibitor bind to other part of the enzyme. Do they both occur?
nitrates are used in making which part of the nucleotides?
are there only one formula Ventilation rate= tidal * breathing rate in that gaseous exchange chapter. If there any more please tell them

 

[thu]

w10_12 q9. Can anyone clear me why it's D?

 

[thu]

q21 from w05. Why is it C not D?

 

[egy]

in non-competitive inhibition does the inhibitor attack to the enzymes active site or does the inhibitor bind to other part of the enzyme. Do they both occur?
nitrates are used in making which part of the nucleotides?
are there only one formula Ventilation rate= tidal * breathing rate in that gaseous exchange chapter. If there any more please tell them

* the non competitive inhibtor will bind to the enzyme but not at the active site so this binding will afect the shape of the active site of the enzyme so the substrate cannot fit in the active site of the enzyme any more and as u add more substrate the reaction will not increase so itis non competitive inhbition
* the nitrogen is used to make the bases of the nucleotides such as the adenine and guanine
* for the last point i will see


like it if usefull

 

[thu]

in non-competitive inhibition does the inhibitor attack to the enzymes active site or does the inhibitor bind to other part of the enzyme. Do they both occur?
nitrates are used in making which part of the nucleotides?
are there only one formula Ventilation rate= tidal * breathing rate in that gaseous exchange chapter. If there any more please tell them

for you 2nd concern, nitrates are used in making the 4 bases adenine, thymine, cytosine and guanine. (see the picture down here). that's all i can help

 

[raamish]

what does terminal bronchiole do and what does respiratory bronchiole do

 

[Babri]

q21 from w05. Why is it C not D?

Because phosphate is what joins two of the nucleotides, there is no phosphate in D so ans is C.

 

[sahania]

View attachment 12694 is the answer A?
View attachment 12698 ans is B because glycogen contains alpha-glucose
View attachment 12699 Ans is C because sucrose breaks down to form alpha glucose and fructose

yes ..it's A

 

[HuN3yy !!]

What is the theoretical number of chemically different dipeptides that may be assembled from 12
different types of amino acids?
A 24 B 72 C 144 D 400

How to do it ?????????? help rogue94