AS LEVEL BIOLOGY... discuss here AS students only :)

[ruler_of_the_world]

O.O NEVER SAW SUCH A THING ?!

Lol y not? Too mind boggling?

 

[mariyam95]

Lol y not? Too mind boggling?

dude its better to understand whats is resolution .. if u understand it u can tell which has the better resolution

 

[mariyam95]

y is transpiration is an inevitable consequence of gas exchange??



and outline the roles of phospholipids.cholestrol.glycolipids,protien andd glycoprotiens

phosphoipids ... form the bilayer and a barrier to polar molecule
cholestrol..maintain the fluidity of the membrane and maintain mechanical stability
glycolipids...staiblise the membrane structure
protein.. act as transport channels
glycoprotiens...receptors to chemicals and help in communication and recognition of cells

 

[mariyam95]

Can somebody explain the bohr effect in a simple way?

co2 + h2o --->h2co3
h3co3---->H+ + HCO3
HbO + H+ ----> HHb
when co2 concentration increase it dissolve in water to give carbonic acid therefore increasing H+ ions in the blood
H+ lowers the pH of the blood and makes the blood acidic.. to restore the normal PH of the blood :
haemoglobin now has low affinity for oxygen it releases oxygen and bind to H+ ion to mop it up producing haemoglobanic acid
the removal of the H+ ions restore the normal ph of the blood

so high co2 high h2co3 high H+ low ph therefore lower affinity and the curve will move to the right

 

[NouranAyman]

Do we have to know causes of sickle cell anaemia??

 

[daredevil]

y is transpiration is an inevitable consequence of gas exchange??



and outline the roles of phospholipids.cholestrol.glycolipids,protien andd glycoprotiens

transpiration is the evaporation of water through the stomata.
gas exchange is done through the stomata.
for the gas exchange to occur the stomata oopen up. the water withing the leaf moves towards the epidermis as water potential is higher inside the leaf than it is on the outside. thus side by side with the gases moving in and out the water also gets a pathway to move out of the leaf and thus transpiration occurs.

protein is simple the building block of our body cells and its as simple as that. other than that u can say they form enzymes, and all but all in all they have a synthetic purpose.
glycoproteins and glycolipids have almost all the same purposes. they act in cell to cell recognition [antigens]. they are hormone receptors. make hydrogen bonding with the surrounding area and make a stabilized structure.
phospholipids basically make up certain fats. they esp make up cell memberane bilayers and their structures are important in the sense that they have the two hydrophobic tails and a hydrophilic head which accounts for the plasma memberane structure.
cholestrol makes up part of the cell membrane and keeps the mmberane fluid which is important for a number of reasons.

 

[daredevil]

Do we have to know causes of sickle cell anaemia??

ummm i don't think there is a special cause for it except mutation. and no we are not supposed to know what mutates to what for sickle cell anaemia i thnk. it is just a result of mutaiton is all i guess

 

[NouranAyman]

ummm i don't think there is a special cause for it except mutation. and no we are not supposed to know what mutates to what for sickle cell anaemia i thnk. it is just a result of mutaiton is all i guess

thankss

 

[Ahmed Khalel]

Do we have to know the structure of deoxy ribose ,ribose ,and the bases?

 

[MÁťT PŭמҚ]

Do we have to know the structure of deoxy ribose ,ribose ,and the bases?

not really!!

 

[daredevil]

Do we have to know the structure of deoxy ribose ,ribose ,and the bases?

yes to deoxyibose and ribose but the bases i don't think so. just know that A and G have a double ring structure with one double bond in each ring and the uracil, thyamine and cytosine have single rings with 2 double bonds each. and yes know that G and C hav triple bond whiile A and T or U have double bonds.

 

[daredevil]

not really!!

umm seriouslyy?? :O bcz i'm pretty sure we have to at least a bit. look here:

yes to deoxyibose and ribose but the bases i don't think so. just know that A and G have a double ring structure with one double bond in each ring and the uracil, thyamine and cytosine have single rings with 2 double bonds each. and yes know that G and C hav triple bond whiile A and T or U have double bonds.

 

[MÁťT PŭמҚ]

umm seriouslyy?? :O bcz i'm pretty sure we have to at least a bit. look here:

yeah only a bit lyk how it looks lyk..!! we dont have learn der molecular formula ..!!

 

[daredevil]

yeah only a bit lyk how it looks lyk..!! we dont have learn der molecular formula ..!!

of the ribose and deoxy we have to know even the displayed formula my friend but its almost like glucose which we already know... and for nitrogen bases we only need to know wat they look like

 

[MÁťT PŭמҚ]

of the ribose and deoxy we have to know even the displayed formula my friend but its almost like glucose which we already know... and for nitrogen bases we only need to know wat they look like

okio.. well i already knw it ..!! so no worries..

 

[daredevil]

okio.. well i already knw it ..!! so no worries..

 

[Ahmed Khalel]

Thanks

 

[MÁťT PŭמҚ]

(iii) After circulating in the blood for a short time, the pathogen enters liver cells of the
newly infected person and then enters red blood cells.
why does it enter the liver cell ..?

.

PATHOGEN REPRODUCE IN LIVER CELLS AND GAIN ITS FOOD AND ENERGY FROM LIVER CELLS..!!

 

[Lujain M.]

guys can someone pls give me the link to mary jones revision guide AS bio?

 

[Anto P Biju]

what is da syllabus in short ........ anyone plz help???