Human Anatomy And Physiology PYQ 1

Q. Define tissue and explain in brief epithelial tissue.

TISSUE- A group of cell having similar function and structure is called as tissue

There are four type of tissues

1. Epithelial tissue 
2. Connective tissue 
3. Muscular tissue
4. Nervous tissue

1)Epithelial tissue-

• These tissue type cover the body and lines of cavity ,hollow organ ,tubes ,  
• It is also found in gland (exocrine and endocrine)
• These cells are very closely packed in a form of continuous sheet
• The intracellular substance(matrix) is minimal
• These lie in basement membrane

function of basement membrane -repairing of cell, selectively permeable membrane, and separation between epithelial and connective tissue 

Function of Epithelial tissue-

1. Protection - Covers the entire body surface and act as a first line of defense
2. Absorption - absorbs nutrients and water
3. Secretion - secrete - enzyme, mucus, saliva, hormones and sweat etc.
4. Sensation - epithelial tissue of nose, eye, ear, toung, sensory organs
5. Exchange of substance - (transport) between underlining tissue and body cavity

Classification of Epithelial Tissue

1) Simple epithelial -(single layer of cell)

• single layer of identical cell
• usually found in an absorptive or secretary surface
• types are normal according to shape of cell

Types of Simple epithelial tissue

1. Simple squamous epithelial tissue -

•  A single layer of  cell
• It is present in lining of heart , lining of blood vessel, lymph vessel and collecting duct from from nephron 
• Actively involved in transport by diffusion

2.Simple cuboidal epithelial tissue -

• A single layer of cube like cell
• It is found in kidneys, tubules and in some gland like thyroid
• function - secretion and absorption

3. Simple columnar epithelial tissue -

• A single layer of rectangular shape cell
• It is found in lines of digestive tracts , bronchi, uterine tubes and uterus
• function- absorb and secrete mucus and enzymes

2)Stratified Epithelial Tissue-(several layer of cell)

• multiple layer of various cell shape
• continuous cell division in the lower layer and it pushes cell above when they are shed
• protect underlying structure

Types of stratified epithelial tissue 

1.stratified squamous epithelial tissue -

• composed of several layer of cell 
• in the deepest layer mainly columnar cell present and they grow towards surface 
• function-protection

these cells grow towards -

1. keratinized stratified epithelial tissue- found in dry surface subjected to wears/tear i.e. skin hair and nails
2. Non keratinized stratifies epithelial tissue - it lines the mouth cavity oesophagus and vagina 

2.stratified cuboidal epithelial tissue - 

• multiple layer of cuboidal cell in top most layer
• function - protection of ducts of various glands 

3.stratified columnar epithelial tissue - 

• top most layer of column cells is known as stratified columnar epithelial tissue
• it is found in male urethra , ducts of salivary glands 
• function - protection and secretion .

----------------------------------------------------------------

ONLY FOR EDITOR

All Material

Beat Mark

Shake Effect