AS Biology P1 MCQs Preparation Thread

[Sakib]

w 11/paper 11/ Q-6,14,30, 34,40. Somebody help me!

 

[Sughontha]

im confused about the protein structures needed to maintain shape of active site? is it only 3° or primary also important?because of the amino acids?

 

[Sughontha]

Its Niche(C) because the description above refers to the role played by the tree.

but the answer in tye w12 paper is ecosystem!

 

[Aries_95]

im confused about the protein structures needed to maintain shape of active site? is it only 3° or primary also important?because of the amino acids?

Primary, secondary and tertiary all are important to maintain shape of active site.

 

[Sughontha]

ote="Aries_95, post: 603724, member: 73536"]Primary, secondary and tertiary all are important to maintain shape of active site.[/quote]

Primary, secondary and tertiary all are important to maintain shape of active site.

w02 question 12 then??

 

[Aries_95]

ote="Aries_95, post: 603724, member: 73536"]Primary, secondary and tertiary all are important to maintain shape of active site.

w02 question 12 then??[/quote]

The questions asks for the globular shape of the enzyme. since globular shape is formed due to interactions between the R groups of the side chain giving rise to a ball shaped molecule, the globular shape is maintained by the tertiary structure (Tertiary structure involves interactions between the R-groups).

 

[Sughontha]

so,the general shape of the active site is also dependant on 3° only but the enzyme specificity is dependent on all 1,2,3,4°?

 

[ahmed abdulla]

18 Which statement describes a cell that is capable of reproduction and belonging to a haploid
organism?
A It has chromosomes that contain one polynucleotide chain.
B It is capable of carrying out a reduction division to form gametes.
C It possesses two copies of each gene as a result of fertilisation.
D It will undergo cell division by mitosis during asexual reproduction.

ans is D .. but i am pretty sure its B ... from o/n 2009 va'11

 

[Bluejeans#]

37 An enzyme hydrolyses the two heavy polypeptide chains of an antibody molecule. The hydrolysis
occurs at the hinge region and breaks the antibody into three fragments.
How many of these fragments are able to bind to antigens?
A 0
B 1
C 2
D 3


kindly explain dis ques

 

[fizzah96]

18 Which statement describes a cell that is capable of reproduction and belonging to a haploid
organism?
A It has chromosomes that contain one polynucleotide chain.
B It is capable of carrying out a reduction division to form gametes.
C It possesses two copies of each gene as a result of fertilisation.
D It will undergo cell division by mitosis during asexual reproduction.

ans is D .. but i am pretty sure its B ... from o/n 2009 va'11

as it is already haploid so it cannot undergo meiosis and to maintain the chromosome no. it will carry out mitosis and asexual reproduction so its D not B because chromosome no. cannot be further reduced.

 

[Boo]

Hey, can someone explain to me QNS 32 in o/n 04 how do we get the ans B? :s

 

[ahmed abdulla]

as it is already haploid so it cannot undergo meiosis and to maintain the chromosome no. it will carry out mitosis and asexual reproduction so its D not B because chromosome no. cannot be further reduced.

thanks ...
can u help with this

 

[fizzah96]

thanks ...
can u help with this

see at 1 atrio ventricular valves close and semilunar are also closed.semilunar open at 2,so the time period between 1 and 2 is 0.03 sec(both are closed)
at 3 semilunar open while atrioventricular are still closed that open at 4.the time period between these is 0.04 sec.so total time period becomes 0.07 sec.

 

[sweet life]

http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_s12_qp_12.pdf

guys sorry can u plz just tell me Q1 and Q11
it will be a great help thank you!

 

[sweet life]

http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Biology%20(9700)/9700_s12_qp_12.pdf

plz can any one help me with Q1 ,11 and 30 of this paper it will be really a great help thank you

 

[h4rriet]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_s12_qp_12.pdf

plz can any one help me with Q1 ,11 and 30 of this paper it will be really a great help thank you

1. That's just something you have to memorise.
11. A glycogen molecule has 1,4 and 1,6 bonds.
30. The stroke volume will increase when the ventricular end-diastolic volume increases, but not proportionally because not all the blood will leave the systole.

 

[sweet life]

1. That's just something you have to memorise.
11. A glycogen molecule has 1,4 and 1,6 bonds.
30. The stroke volume will increase when the ventricular end-diastolic volume increases, but not proportionally because not all the blood will leave the systole.

Thank you soo much

 

[Pwincessajwa]

i need help in so many papers will anyone help plz ?

 

[HubbaBubba]

Hey, can someone explain to me QNS 32 in o/n 04 how do we get the ans B? :s

Tidal volume is the amount of air breathed in and out normally. As you can see in the first thirty seconds of the graph the tidal volume is at a constant 500 cm3. As for the Vital capacity - it is the maximum amount of air breathed out so if you count the number of squares for the large exhalation bit it would be 14.5 square. Since each 4 squares are 1000 cm3 that would equal to roughly (1000 + 1000 + 1000 + 500 + 250) which is 3750 cm3

 

[HubbaBubba]

i need help in so many papers will anyone help plz ?

Just post what you need help in, and I'll try to help