~AS Bio doubts Here !!~

[aquariangurl]

CAN anyone give a detail explanation of exocytosis and endocytosis

Look Endocytosis is the engulfing of the material by the plasma membrane to form vacuoles
Examples of endocytosis are Phagocytosis (cell eating) This is lyk this bulk uptake of solid material Like how phagocytes engulf bacteria during immune response
& Pinocytosis (cell drinking) This is the bulk uptake of liquid It's sorto like taking up nutrients from cells surrounding it.
Then exocytosis is pretty much the opposite, Materials are REMOVED from the cell like for example secrection of enzymes. The process goes like first the protien is synthesized by the RER & then the vesicles carry the protien to the cell surface membrane to be released.
As simple as that. Did you get it?

Ya where did the golgi appartus go i guess this how to goes
from RER the protein go to golgi appartus in here it get modified, packed and budds off as vesicle at the other end of the tube it travels to cell membrane ,fuses with it And its then realeased as vescile out of the cell

i suck at explaining ... is this rght

Yup it is I didn't know you wanted it in SUCH detail so I just gave an Overview..

 

[nidzzz09]

plz help me for this question..

Explain why sickle cell anaemia is common in areas where malaria is endemic ?

hey i guess the question yu ask is not correct cuz i know sickle animal is nt common in areas of malaria cuz when a person has sickle anemia the RBC are in an inapporiate form for the plasmodium to exploit as it habit so plasmodium dies no malaria :Yahoo!: as less space in rbc the becume sicke shape rght

No i dont think question is wrong cuz i got this question frm past paper only its frm O/N 01 ques no 6 (b) check out

Do yu have the link

 

[nidzzz09]

can someone explain the difference between an antibody and an antibiotic and each of their functions????

Chemical Structure
Antibodies and antibiotics typically have very different chemical structures. Each antibody molecule contains two large proteins called heavy chains that bind to two smaller proteins called light chains, all of which bond together to form a Y-shaped structure, according to the University of Arizona. The ends of the light and heavy chains form the variable region, which allows each antibody to bind to one specific molecule, or antigen, to help fight off a specific type of infection. Although the variable region differs from antibody to antibody, the general structure of each antibody molecule remains consistent. In contrast, antibiotics may contain a wide range of structures, including series of chemical rings, and do not exhibit the same structural consistency as antibodies.

Origin
Another major difference between antibodies and antibiotics is in their respective origins. Antibodies are naturally produced in the body by immune system cells. In response to an invading pathogen, the stimulation of the immune system triggers the synthesis of antibodies that can be used to fight off its infection. All naturally occurring antibodies are generated within the body in specialized blood cells called B cells.



Antibiotics, on the other hand, can come from a range of sources. These chemicals may be purified from plants or microorganisms that naturally produce these chemicals to fight off infection.

Mechanism of Action
Antibodies and antibiotics also differ in their mechanism of action: the way they kill pathogens and fight off infection. Antibodies produced in B cells bind antigens,of pathogen. Once an antibody binds an antigen, the antibody triggers an activation of the immune system. The antibody signals for immune system cells to engulf and digest the infectious invader, helping to neutralize the infection.


Antibiotics, on the other hand, typically work by inhibiting essential cellular functions the infectious bacteria requires to live and divide. Penicillin, the first discovered antibiotic, works by preventing synthesis of the cell wall, an essential step in bacterial cell division, according to Elmhurst College. Without proper cell wall formation, water can rush into the bacteria and cause the cell to burst, thereby treating the infection

 

[arsimme]

nidz : NA i dont have link dont u have it in ur past papers ??

 

[filza94]

explain me transport in plants according to syllabus plzzz

 

[arsimme]

can somebody answer this question?
Antibiotics are used to treat people with bacterial infections.
Explain the danger of the widespread use of antibiotics to treat disease ?

 

[hassam]

i guess its 4 marks....
variation present in bacterial population due to random mutation during replication...mutant resistive strains of bacteria may emerge as a result of this...so if antibiotic is used it ll kill off the weaker strain and resistant strain will have a selective advantage over the other one thus rendering the antibiotic used ineffective

 

[girlscampisra]

please tell me how companion cells load sucrose into phloem sieve tubes!

 

[nidzzz09]

plz help me for this question..

Explain why sickle cell anaemia is common in areas where malaria is endemic ?

hey i guess the question yu ask is not correct cuz i know sickle animal is nt common in areas of malaria cuz when a person has sickle anemia the RBC are in an inapporiate form for the plasmodium to exploit as it habit so plasmodium dies no malaria :Yahoo!: as less space in rbc the becume sicke shape rght

No i dont think question is wrong cuz i got this question frm past paper only its frm O/N 01 ques no 6 (b) check out

ok do yu have the mS
i cant find it

 

[arsimme]

No even there is no mark scheme for it..thats the main problem

 

[filza94]

y u guyz ignoring me n my coment wat da hell u all dont answer mee...

 

[ashutoshamatya]

could u plz explain me what is arteriole diastole??

 

[girlscampisra]

when atria relaxes!

 

[filza94]

 

[arsimme]

y u guyz ignoring me n my coment wat da hell u all dont answer mee...

NNobody is ignoring u ..i din answer u cuz i din know the answer to ur question.

 

[filza94]

not u rest of them..

 

[Xthegreat]

hey, regarding the question, why sickle cell anaemia is common in areas where malaria is endemic ?

- the plasmodium which is the causative agent of malaria hides in our red blood cell
- shortly after it enters our blood stream
- known as antigenic concealment.
- however if the person has anaemia, the person would have deform red blood cells
- plasmodium does not hide in deform red blood cells
- hence it remains in the blood stream where it is possible for our body's immune system to detect
- our immune system can therefore kill the plasmodium

*if you have learnt A2, the you would know about natural selection
- anaemia is caused by faulty genes and rightfully should have been eliminated after so many generations as anaemia is deathly.
- however if a person is half anaemic ( meaning he/she have half NORMAL red blood cell and another half deform red blood cell) they can actually survive.
- considering the fact that the plasmodium cannot conceal themselves in the deform red blood cell
- half anaemic people has a HIGHER chance to survive malaria than those who is perfectly normal ( meaning non-anaemia )
- hence after so many generations, anaemia has not yet been eliminated.
- and it is common because it gives people a higher survival rate from malaria than those without anaemia.

 

[filza94]

answer me dix all

1. Difference between Prokaryotic/Eukaryotic ; Plant/animal cell.
2. Questions on Lipids, triglycerides, pospholipids.
3. Relationship between structure and function of Haemoglobin and Collagen.
4. Question on thermal and solvent properties of water.
5. Effect of temperature, enzyme conc. , substrate conc. on enzymes.
6. Roles of components of cellmembrane ; questions on facilated diffussion and active transport.
7. Questions on mitosis and cytokinesis on animal cell, read cell mutations also
8. Transpiration of plants, movement of water in plant (including symplast and apoplast)
9. Components of blood vessels and blood including their function, Tissufluid and lymph
10. Effect of tar. nicotin and CO. Lung cancer, Prevention of CHD.
11. HIV and measels transmission, cause, prevention, eradication. How antiboitics work.
12. Structure function of antibodies.Complete nitogen cycle.

 

[arsimme]

answer me dix all

1. Difference between Prokaryotic/Eukaryotic ; Plant/animal cell.
2. Questions on Lipids, triglycerides, pospholipids.
3. Relationship between structure and function of Haemoglobin and Collagen.
4. Question on thermal and solvent properties of water.
5. Effect of temperature, enzyme conc. , substrate conc. on enzymes.
6. Roles of components of cellmembrane ; questions on facilated diffussion and active transport.
7. Questions on mitosis and cytokinesis on animal cell, read cell mutations also
8. Transpiration of plants, movement of water in plant (including symplast and apoplast)
9. Components of blood vessels and blood including their function, Tissufluid and lymph
10. Effect of tar. nicotin and CO. Lung cancer, Prevention of CHD.
11. HIV and measels transmission, cause, prevention, eradication. How antiboitics work.
12. Structure function of antibodies.Complete nitogen cycle.

PRokaryotic Eukaryotic
1. cells have 0.5 to 5 micrometer daimeter. 1. Cells are commonly 40 micrometer and are 10 000 the volume of prokaryotic cells.
2. DNA is circular and lies free in cytoplasm. 2. DNA is not circular and is content in nucleus. the nucleus is surrounded by nuclear envelop.
3. DNA is naked. 3. DNA is associated with proteins forming a structure called chlromosome.
4. No ER present. 4. ER is present may b ribosomes attached to it.
5. Slightly smaller ribosomes. ( 18 nm ) 5. Cell wall may b present.
6. Cell wall is is present,

 

[filza94]

thanks can u giv me all answerss