A level Biology: Post your doubts here!

[Lola_sweet]

Haemophilia is explained in page 379 of new book. Maybe you don't have that, but thanks to My Name you can see it here:
CIE coursebook for A2 Biology (4th edition for the 2016 syllabus)

The specific image with info on haemophilia is image 16.

If you already understand sex linked inheritance, the diagram in that page should be self explanatory, but if you still have doubts I'll be happy to explain

i understand haemophilia and i read that page
i also understand hw its sex linkage and what effect that has

outline the effects of mutant alleles on the phenotype in the
following human conditions: albinism, sickle cell anaemia,
haemophilia and Huntington’s disease

^but this is the statement of syllabus
and ik hw mutation is related to all diseases except haemophilia

thats the doubt

 

[Rizwan Javed]

View attachment 59095

Is it D?

 

[HumptyR]

Is it D?

Yes :3

 

[Rizwan Javed]

View attachment 59095

Yes :3

Look, 1.0 mol dm^-3 solution is hypertonic to the environment in cell. So water will move out of the cells leading to plasmolysis or shrinking of cells. Whereas 0.1 moldm^3 solution is hypotonic to the cell environment, so the water will move into the cell, leading to swelling of cell.

 

[HumptyR]

 

[HumptyR]

Look, 1.0 mol dm^-3 solution is hypertonic to the environment in cell. So water will move out of the cells leading to plasmolysis or shrinking of cells. Whereas 0.1 moldm^3 solution is hypotonic to the cell environment, so the water will move into the cell, leading to swelling of cell.

thanks RIZZY!!

 

[Rizwan Javed]

View attachment 59097

C? :3

 

[HumptyR]

C? :3

yes

 

[zahra azam]

View attachment 59097

It will be C i guess
Cuz the light microscope can magnify up to 2000x
Its just 400x

 

[zahra azam]

N if u have seen a cell under light microscope...only the nucleus is visible

 

[Rizwan Javed]

yes

It's because the organalles like mitochondria, golgi bodies, Rough endoplasmic reticulum are not visible in light microscope.

 

[HumptyR]

It will be C i guess
Cuz the light microscope can magnify up to 2000x
Its just 400x

Is it not related to resolution in anyway?

 

[zahra azam]

Is it not related to resolution in anyway?

Yeah but the qs says 400x ...thats a hint
U dont really have to learn the resolutions tho

 

[Rizwan Javed]

Is it not related to resolution in anyway?

Of course it is related. The least possible size that light microscope can view is about 200 nm. where as the structure are much much smaller than this.

 

[HumptyR]

N if u have seen a cell under light microscope...only the nucleus is visible

otay zarra

 

[Lola_sweet]

Is it not related to resolution in anyway?

yeah it is
low resolution means you cant differentiate between 2 points
so as light microscope has low resolution (no matter hw high magnification) you can nt see any organelle but a stained nucleus

 

[zahra azam]

Which paper is that humpty?

 

[HumptyR]

Which paper is that humpty?

s2010

 

[HumptyR]

and i am not humpty fgs

 

[zahra azam]

s2010

Paper 1?