10. Compare prokaryotic cell and eukaryotic cell.
Answer:
Organisms are classified into five
kingdoms which are Prokaryotae, Protoctista, Fungi , Animalia and Plantae,
there are two types of cell, prokayotic and eukaryotic cell.
The prokaryotic cell (mostly
bacteria and cyanobacteria) has its DNA not enclosed by nuclear membranesand
lack organelles bounded by a double membrane.The eukaryotic cell( include
protoctists, fungi, animal and plant) have chromosomes surrounded by
well-defined nuclear membrane. A prokaryotic cell's DNA is not surrounded by
double-membraned nuclear envelope, the genetic material is a circular double
strand of DNA. Most of the prokaryotes does not have plasmids, mitosis and
meiosis does not occur in prokaryotes, therefore, there are no spindle
formation too. Prokaryotic cell has simple and little organelles, it has 70S
ribosome, food granules, pili and flagella etc. The prokaryote has mesosomes
instead of mitochondrian which are present in eukaryotic cell. The cell are not
compartmented and none of them is surrounded by an envelope, which mean the
organelles are not arranged nicely. Thus, a prokaryotic cell does not function
as efficient as a eukaryotic cell. with its simple structurem, only unicellular
or filamentous prokaryotes exist.
There are different kind of
eukaryote, there are unicellular, filamentous or truly multicellular organisms
of eukaryotic cell. An eukaryote has chromatin which contain DNA and proteins
called histones which will condense to form chromosomes during cell division.
Mitosis, meiosis and spindle formation occur in eukaryotic cell. Eukaryotes
have larger ribosomes(80S), the ribosomes may be attached to endoplasmic
reticulum.eukaryotes have many specified organelles, the organelles are
compartmented and more organized in order to function efficiently. There are enveloped
bounded organelles such as nucleus, mitochondrian and chloroplast and single
membrane bounded organelles such as Golgi apparatus, lysosomes, vacuoles, and
microbodies.
Prokaryotes except blue green
bacteria use mesosomes for respiration while eukaryotes use mitochondrian to
undergo respiration. The eukaryotic cell is more complex than the prokaryotic
cell.
Assignment submitted by group 1 2011/2012 (IBM)
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