1. Medical biology cytology
LEC1. INTRODUCTION AND CELL MEMBRANE
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

2. What is biology Biology is the study of all living things
Living things are called organisms
Organisms include
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

3. Biologists classify cells into two broad categories—the prokaryotes and eukaryotes.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

4. classification according to the number of the cell
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

5. All living organisms share common characteristics:
They have levels of organization
acquire materials and energy from the environment
reproduce and develop
maintain homeostasis
respond to stimuli
Have an evolutionary history and are adapted to a way of life
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

6. level of human organization
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

7. lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

8. What is the cell
Cell is a smallest basic structural and functional unit of all living organisms that maintain proper homeostasis of the body.
The science that studies the microscopic appearance of cells known as cytology
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

9. The human organism present about 200 different cell type
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

10. In general the basic human cell component are:
Plasma membrane (plasmalemma).
Cytoplasm: that include cytosol, cell organelles and inclusions.
Nucleus.
Cytoskeletal
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

11. TEM Of Human cell structure
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

12. Plasma membrane
Plasma membrane is a thin semi permeable membrane, composed from lipid and protein that surrounded cytoplasm of a cell and control the passage of substance into and out of the cell.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

13. TEM of sectioned cell membrane shows as two dark layers plus one clear layer from the gap between them.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

14. Cell membrane models
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

15. Structure of plasma membrane
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

16. Membrane lipids (phospholipids)
The building blocks of all cell membranes are phospholipids bilayer, each layer consisting of two hydrophobic fatty acid chains (non polar tail) linked to a phosphate- containing hydrophilic head group(polar head).
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

17. Membrane lipids (cholesterol)
Cholesterol is reduces the permeability of the membrane to the most biological molecules.
Have important role in Stability of cell membrane and make it more rigid
Regulate the fluidity of phospholipids bilayer.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

18. Membrane proteins large protein molecules
1. Integral proteins
2.Peripheral proteins
large protein molecules
embedded directly within the lipid bilayer
closely attached protein.
small protein molecules
not inserted into the lipid bilayer but are associated with the membrane indirectly
loosely attached
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

19. lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

20. Membrane glycolipids and glycoprotiens
Glycolipids have a structure similar to phospholipids except that the hydrophilic head is a variety of sugars joined to form a straight or branching carbohydrate chain.
Glycolipids have a protective function.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

21. Membrane glycolipids and glycoprotiens
Glycoprotein (glycocalyx)
Is delicate fuzzy cell coat
Composed of carbohydrate molecules that are attached to the integral proteins of the cell membrane and project from the external cell surface.
Have an important role in cell recognition, cell to cell attachment or adhesions and act as receptor or binding sites for different protein hormones.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

22. Glycoprotein (glycocalyx)
Also called cell coat
Cell coat present on special type of cell and don’t present on others make some cell effect with virus, bacteria, hormones and drugs.
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18

23. Thank you
lecturer Farah E.Ismaeel
24 تشرين الثاني، 18