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Last Island Wednesday, February 29, 2012 11:17 PM

Single celled micro organism

SADIA SHAFIQ Wednesday, February 29, 2012 11:26 PM

[QUOTE=Last Island;408638]Single celled micro organism[/QUOTE]

Thanx for answering. First i thought to elongate it just for the sake of discussion. Now quit it. Cell are of two types one are called prokaryotes and other are eukaryotes. Bacteria has DNA NOT ENvoloped in cell. Virus is also a cell having DNA. And we says these are prokaryotes. Mitochondria and chlophyrl have that DNA and cellualar membrance plus plasma which define it as prokaryotes. At that time i am not online from PC SO cant link it. You can verify it via above mentioned classification.

Regards!

SADIA SHAFIQ.

Last Island Wednesday, February 29, 2012 11:50 PM

You are on your pc now so please search and show me the cell structure of chlorophyll. I really want to see its plasma, DNA and cellular membrane.

Hamidullah Gul Thursday, March 01, 2012 12:02 AM

up-till my bachelors in botany i didn't know that chlorophyll is a cell........:confused:

SADIA SHAFIQ Thursday, March 01, 2012 12:56 AM

[QUOTE=Last Island;408666]You are on your pc now so please search and show me the cell structure of chlorophyll. I really want to see its plasma, DNA and cellular membrane.[/QUOTE]

I am wrong in assertion? Ah! You do not believe what me saying. If i am and was on pc then certainly link it.

1.plastids have their own genome.what is genome ? Only that organelle signfy it as prokaryotes. You can compare it with cyno bacteria.
And second see video link of cell structure of plants by channel khanacademy. This channel has received award internationally and appreciated on CNN.

Last Island Thursday, March 01, 2012 01:04 AM

Please do not go off track. I am not talking about plastics, bacteria, prokaryote and eukaryote. We are discussing Chlorophyll as a Cell. I havent said that you are wrong in assertion. I, and many others, want to see the cell structure to enhance our knowledge and there is nothing bad about it. Is there?

pureapak Thursday, March 01, 2012 01:14 AM

@ Sadia

Chlorophyll is substance present in chloroplast, one of the tiny organells of a plant cell. It captures light and helps plant prepare own food by the process of photosynthesis.

It is not a cell by itself but a minute ingredient of a cell..... :)

mano g Thursday, March 01, 2012 02:56 PM

chloroplast is the unique cell organelle found in plant cell only, it is absent in animal cell, now chlorophyll is a pigment inside chloroplast that is used by the plants in the process of photosynthesis,

so, chlorophyll is a pigment in chloroplast of plant cell, it is not a ''cell''.

candidguy Thursday, March 01, 2012 04:28 PM

[QUOTE=mano g;408822]chloroplast is the unique cell organelle found in plant cell only, it is absent in animal cell, now chlorophyll is a pigment inside chloroplast that is used by the plants in the process of photosynthesis, [COLOR="Navy"]It is only formed in the presence of sunlight.[/COLOR]

so, chlorophyll is a pigment in chloroplast of plant cell, it is not a ''cell''.[/QUOTE]

Exactly.

Sis, Sadia, I know where you're coming from. You're right in saying Mitochondria and chloroplast(a variant of plastids, otheres being chromoplast and leaucoplast etc) have their own genomes. But they still can't be called as cells. Why? Cell is defined as [I]'The structural and functional unit of life'[/I]. What that means is, a cell has all the basic structure and performs all the functions a living thing can perform. These functions include, Growth, digestion, reproduction, response to stimuli, homeostatisis etc etc. A chloroplast though may have DNA, it lacks other above mentioned properties. As to chloroplast, it's a different thing altogether. It's just a pigment, that is formed inside CHLOROPLASTS in the presence of sunlight, necessary for photosynthesis.

candidguy Thursday, March 01, 2012 05:17 PM

EDS MCQs that i remember (please do point out the errors)

1. Electricity and Magnetism are
a)Two aspects of same force....b) completely opposite....c)both a & b...d)none of the above
[B]Answer: A[/B]
2.Richest source of omega 3 acids
a) fish oil b) sunflower c)----- d) none of the above
[B]Answer: A[/B]
3. which one of the following is a mammal
whale (sorry, cant recall any other option)
[B]Correct[/B]
4.which one of the following reaction happens on Sun
a. nuclear fusion of hydrogen into helium
b. nuclear fission of uranium and ____
c.nuclear fission of plutonium and ___
d.none of the above
[B]Answer: A[/B]
5.one light year is equal to
a. the time it takes the light to travel from the surface of the sun to the earth
b. distance covered by light in one solar year
d.none of the above
[B]Answer:B[/B]
6. Atmospheric pressure at sea level
a. 1 psi
b. 14.7
c. 32 psi
d.none of the above
[B]Answer: B[/B]
7. weight on the moon
a.same as that on the earth
b. double the weight on earth
c.one sixth of earth weight
d.none of the above
[B]Answer: C[/B]
8. ibn zuhr , writer of Al-Taisir was, pioneer of
a. surgery
b.calculus
c. astronomy
d.none of the above
[B]Answer:A[/B]
9. in his book kitab al jabr wal muqabla, al khawarizmi
a.solved linear and quadratic equation
b.c.d
[B]Answer:A[/B]
10. "Truth is *insert lambi si philosophical quotation* " which famous scholar of 11th century said that
a. plato
b. Al Haythem
c.aristotle
d.none of the above


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