Biology MCQ thread..!!

[hassam]

CHEK ERs

 

[URVASHI]

where can i find the ms for O/N 02 P1?

 

[thunderingthunder]

do mitochondria and ribosomes contain nucleic acid??

mitochondria, chloroplasts and ribosomes three of them contain nucleic acid..its only the golgi apparatus which does not contain nucleic acid!

 

[farrukh]

damn...its sooo cnfusing....y its D

the ans should be have been C :%)

 

[sakibfaiyaz]

Why should the answer be D and not B?..........(taken from w04 no.21)
"during prophase.....chromatin coils up into dense structures called chromosomes...."

 

[hassam]

cos chromosomes are present from the interphase.....!!!

 

[sakibfaiyaz]

cos chromosomes are present from the interphase.....!!!

Oh right ...i mixed up chromosomes with "chromatids"

 

[sweetiepie]

@ urvashi i have answers in my booklet which question u want telme...

 

[farrukh]

In most ecosystems, the greatest amount of energy flows through which trophic level?

A. Secondary consumers
B. Herbivores
C. Decomposers
D. Carnivores

June 99

 

[Xthegreat]

In most ecosystems, the greatest amount of energy flows through which trophic level?

A. Secondary consumers
B. Herbivores
C. Decomposers
D. Carnivores

June 99

ans : C ?

 

[sweetiepie]

which organelles does nucleic acid present???

 

[hassam]

mitochondria choloroplast lysosomes nucleus ribosomes

 

[icanhelp]

why not golgi apparatus

 

[Xthegreat]

why not golgi apparatus

cause there it is just NOT possible to find any DNA, rRNA, mRNA which is made up from nucleic acid inside.

 

[Xthegreat]

9 Which statement about triglycerides is correct?
A They are made up of three fatty acids combined with glycogen.
B They are more saturated with hydrogen compared with phospholipids.
C They form a bilayer in the membranes of cells.
D They have a lower ratio of oxygen to carbon compared with carbohydrates.
i know the D is anser bt wats wrong with option B

it's just a fact that triglycerides are less saturated with hydrogen compared with phospholipid. go and find the structure and compare and count yourself id you don't believe.

 

[Xthegreat]

28 When one molecule of oxygen combines with haemoglobin it makes it easier for the next oxygen
molecule to bind, which makes it easier for the next molecule of oxygen to bind.
Which orders of protein structure change to allow this to happen?
A primary and quaternary
B primary and secondary
C secondary and tertiary
D tertiary and quaternary
how the HELL quarternary structure changed....are examiners DUMB or ME

the answer is D rite? do u not read your text book? when one molecule of oxygen binds to the haemoglobin, the haemoglobin is slightly distorted making it easier for the next oxygen molecule to bind.

how exactly do the structure change i cannot tell cause it is not in our syllabus, but the haemoglobin molecule just changes shape when the you squeeze a oxygen molecule in and it is just obvious that the primary cannot change.

protein structures are like primary to secondary then to tertiary then quaternary. so if the shape changes of course the sequence goes the other way round.

 

[sweetiepie]

have anyone has done specimen papers....

 

[Xthegreat]

damn...its sooo cnfusing....y its D

ever heard of transpiration is the consequence of gaseous exchange in plants?

stomata are kept open so that gases can move in and out so due to the open stomata and the factors you should know, transpiration occurs.

the answer is not C because water potential is not maintain when transpiration occurs, it decreases the water potential in the leaf cells.

 

[melon159]

where can i find specimen papers??

 

[ShootingStar]

please explain this question.. :/