Some more differences between Prokaryotic and Eukaryotic

BIOLOGY of the cell.

STUDY 19

Theme: BIOLOGY of a CELL. A CELL AS ELEMENTARY GENETIC MORPHOlogical and FUNCTIONAL BIOLOGICAL UNIT. Membranes.

1. The MEANING of the THEME. The study of a microscopical constitution of organisms allows more deeply to understand the causes of originating of pathologic process, promotes introduction in practice of new methods of diagnostics and treatment.

2. PURPOSE of STUDY. General: To receive representation about a cell as elementary alive system, to understand specifics organization of cells, their difference.

3. The CONCRETE PURPOSES of STUDY:

3.1. To be able to find and to determine the basic components of a cell on microslides.

3.2. To receive representation about a cell ultrastructure.

THE BASIC THEORETICAL ITEMS OF INFORMATION

At present there are two forms of life: non-cellular and cellular. Non-cellular form of life – it is a virus. A virus as such is non-living. It becomes living only when it comes in contact with living cell (or cell-host).

Most living organisms, both plants and animals, are made of a very large number of living units called cells. It is cellular form of life.

The cells are organized structural and functional units containing protoplasm.

The originating of a cell has played a main role for progress of life on our planet. It has ensured:

1) Opportunity of transfer of the inheritable information in lineages of alive organisms;

2) Change of objectes perishing during vital activity by new objectes;

3) Body height and development of organisms by formation of tissues, organs, systems of organs, and all organism as a whole.

There are two kinds of cells: Prokaryotic cells and Eukaryotic cells.

Some more differences between Prokaryotic and Eukaryotic

Prokaryotic

Eukaryotic

1. Bacteria and blue-green algae, (Cyanobacteria). 2. genetic material spread out in the cytoplasm. 3. nucleus and nuclear membrane lacking. 4. no nucleoli. 5. endoplasmic reticulum, Golgi body and mitochondria lacking. 6. genetic material organized in a single closed loop-like chromosome. 7. DNA without protein.   8. cell wall composed of protein, fat and starch. 9. nuclear spindle never formed during cell division. 10. besides a single chromosome, bacteria have circular genetic units (DNA) in the cytoplasm known as plasmids. 11. plasmids serve as autonomous carriers of genetic material from one bacterial cell to the other and often combine with the chromosome of the recipient bacterial cell.

1. all other plant and animal cells.   2. genetic material concentrated within the nucleus. 3. nucleus and nuclear membrane present. 4. one or more nucleoli present. 5. all such organelles present.   6. number of chromosomes varies from 2 to several hundred. 7. DNA associated with histone protein.   8. cell wall always of cellulose.   9. nuclear spindle formed.   10. extra-nuclear genetic material has no comparison with the plasmids.   11. transfer of genetic material is limited to the chromosomes.

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