By Dr. Ladi Anudeep

1. Epithelium
-Ladi Anudeep
ISM-IUK

2. • Human body consists of mainly four basic tissues
• They are: 1) Epithelial tissue
• 2) Muscles
• 3) Connective tissue
• 4) Nervous tissue

3. • Definition of epithelium
• These are special type of tissues which are made of
tightly packed cells that are opposing each other .
• These cells are present on basement membrane.
• They show polarity.
• They have no vascular tissue present in between
them,so they are called as Avascular tissues
• They are mitotically active and they dont have any blood
vessels

5. • Epithelial cells are arranged in two fashions
• 1) Membranous epithelium
• 2) Glandular epithelium
• Membranous epithelium
• In this the cells are arranged in sheath
• In human body, it lines the external surfaces(ex:
epidermis)
• It also lines some internal closed cavities

6. • Examples of internal closed cavities are
• 1) Pericardial cavity
• 2) Pleural cavity
• 3) Peritonial cavity
• It also lines the cardio vascular system which comprises
all the blood vessels.
• The epithelium which lines the blood vessels is called
endothelium

7. • Membranous epithelium lines body tubes that
communicate with exterior
• Ex: 1) Respiratory system
• 2) Gastro-intestinal system
• 3) Urino-genital system

8. • GLANDULAR TISSUE
• in some parts of the
body epithelial tissue
makes glandular tissue
• in glands, cells are
tightly packed with each
other and there is no
vascular tissue and they
can act as glandsand
produce different kinds of
secrections