Animal_Tissues.ppt
- 1. Animal Tissues By Fayez A. Elmabhouh Department of Biology
- 2. Introduction Histology = study of tissues Tissue = group of cells with similar structure and function They are classified according to the shape of the cell, size, intracellular matrix. Four types of human tissues: Epithelial tissue Connective tissue Muscular tissue Nervous tissue The organ can may consists of one (heart) or combination of these tissues (stomach, skeleton, skin)
- 3. Four Tissue Types: 1 2 3 4
- 4. Epithelial Tissues Characterized by: Their closely connected cells. Having very little intracellular substance. Resting on a basement membrane. Arise from the three germ layers. No blood vessels enter between its cell but nerves do Covers body surfaces and forms glands.
- 6. Embryonic Tissues – all adult tissues are derived from one of three embryonic tissues gut Ectoderm = “outside skin” Endoderm = “inside skin” Mesoderm = “middle skin” Cross section through embryo Animal embryo
- 7. Classification of Epithelium 1. Covering epithelia. 2. Glandular epithelia.
- 8. Covering epithelia The primary function of this type of epithelia is protection. Covering epithelia classified according to the arrangement of the cell into simple epithelia and stratified epithelia.
- 9. Simple epithelia These tissues divided into four types according to the shape of cell and location of nucleus. Consists of a single layer of cells that are in contact with the basement membrane.
- 10. 1. Simple Squamous Epithelium: The cells are flat with smooth edges. They appear spindle- shaped in cross section Each cell containing a nucleus in the widest area. Found in the lining blood vessels, covering serosa
- 11. Blood vessel
- 12. Serosa
- 13. Simple Squamous Epithelium Simple Squamous Epithelium Bowman’s capsule
- 15. 2. Simple Cuboidal Epithelium The cells in this epithelium are square-shaped in cross section. Have central and round nucleus. Lining the kidney tubules and Follicles of thyroid gland
- 16. Follicles of thyroid gland
- 18. Simple Cuboidal Epithelium cells single layer of cube shaped cells; large nuclei
- 19. 3. Simple Columnar Epithelium Built of long pillar- shaped cells. Containing an oval nucleus. a. Ciliated: Bronchioles b. Non Ciliated: lining the ileum
- 23. 4. Pseudo-stratified Epithelium Single layer of cells which rest on a basement membrane but do not all reach to the free surface of the epithelium. Their nuclei found at different levels giving the a false stratified appearance. Cells that reach the surface carry cilia at their free ends. Lining the trachea.
- 27. Keratinized: the epithelium is covered with keratin layer which is formed by the dead squamous cells (horny layer) Skin. Non- keratinized: esophagus
- 28. Non- keratinized
- 30. Keratinized: Skin 1. Epidermis (Stratified Squamous Epithelium) 2. Dermis
- 32. Transitional- stratified Found in the urinary tract (urinary bladder) Rest on a non clear and non wavy basement membrane. Its superficial cells are cuboidal in shape, and may contain 2 nuclei. The basal cell layer is formed of high cuboidal cell. The intermediate layer are polyhydral cells. Empty Full, the cell change into to squamous cell
- 36. Glandular Epithelium The cells are specialized in secretion and thus form glands. Formed from collections of Epithelial cell Glands with ducts are termed exocrine Glands without ducts are termed endocrine
- 37. Exocrine Glands 1. Unicellular: formed of single cell present in the respiratory tract and intestinal tract
- 39. Multicellular gland Made of many cells and each consist of a secretary portion and duct. They are either tubular, alveolar in form and may be simple or compound.
- 40. Simple tubular glands In the digestive glands, stomach, Large intestine
- 41. Simple alveolar gland Form of a flask with a round secretary portion and a narrow tubular duct. Mucous and sebaceous gland skin
- 44. Compound alveolar gland Parotid gland