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• Tissues: Group of cell having similar structure performing particular function.
• Plant tissue- Meristematic tissue: This tissue have ability to divide and redivide themselves thereby, providing growth to plants. Classified into apical meristem, intercalary meristem and lateral meristem.
• Plant tissue – Simple Permanent Tissue: It is made up of same type of cells and is classified into parenchyma, collenchyma and sclerenchyma.

	Parenchyma	Collenchyma	Sclerenchyma
Intercellular spaces	Large	Less	No spaces
Cell (Dead / Alive)	Alive	Alive	Dead
Cell wall	Thin	Irregularly thick	Thick
Functions	Food storage and support Chlorenchyma prepares food during photosynthesis Aerenchyma have air in spaces which allow floating of plants in water	Provides flexibility in plants	Provides rigidity and strength to plants

• Epidermis: It is outermost layer of plant that cover whole plant body.

Structure of Epidermis	Functions of Epidermis
Single continuous layer of cell No intercellular spaces Cells are flattened Outer wall is thicker than inner wall	Protection of plants from mechanical injury Absorption of water and nutrients from the soil through hair like structure Thick epidermis in desert plants prevents excess water loss
Contains kidney shaped cell called stomata	Allows the exchange of gases Enhance transpiration i.e. water loss from plant body

• Plant Tissue – Complex Permanent Tissue: Made of more than one type of cell.
  • Complex permanent tissue is classified as xylem and phloem
  • Xylem and phloem makes up vascular bundle, hence, are also known as vascular tissue

  	Xylem	Phloem
  Type of cells	Tracheids Vessels Xylem parenchyma Xylem fibres	Sieve tubes Companion cells Phloem parenchyma Phloem fibres
  Dead / alive cell(s)	Alive: Xylem parenchyma Dead: Tracheids, Vessels, fibres	Alive: Sieve tubes, companion cells, phloem parenchyma Dead: Phloem fibres
  Structure and functions	Tracheids and vessels: Tube like structure Transports water and minerals in upward direction Xylem Parenchyma: Storage of food Sideways conduction of water Xylem fibres: Present between tracheids and vessels Provides mechanical support	Sieve tubes: Tube like structure Walls of tubes contains holes Phloem (Sieve tubes/ companion cells/ phloem parenchyma/ phloem fibres) : Transports food material to all parts of plant body Transportation is done in upward and downward direction

• Distinguish between Xylem and Phloem:
  

  Xylem	Phloem
  Tracheids, vessels and xylem fibres are dead cells.	Phloem fibres are dead cells
  In vascular bundle, xylem occupies centre region	In vascular bundle, phloem occupies outer region
  Transports water in upward direction, i.e. from roots to upper part of stem	Transports food material in all direction
  Provides mechanical strength to plants	Does not provide mechanical strength to plants

• Animal Tissue – Epithelial Tissue:
  • Cells are arranged in tile format
  • Have no intercellular spaces

  Epithelial Tissue	Structure	Location	Function
  Squamous epithelium	Thin and flat Forms thin lining Number of layers of this tissue is called stratified squamous epithelium	Lining of mouth, oesophagus, blood vessels, lung alveoli, skin,etc.	Transports material through selectively permeable membrane
  Columnar epithelium	Column like structure In respiratory tract contains cilia	Inner lining of intestine, stomach, respiratory tract etc	Absorption and secretion occurs Allows particles and mucus to move in right direction
  Cuboidal epithelium	Cube like structure Undergo modification to form gland called glandular epithelium	Lining of kidney tubules, sweat glands, etc	Secretion and absorption of material

• Animal Tissue – Muscular Tissue: Allows movement of body due to presence of contractile proteins.
  

  Muscle type	Structure	Location	Function
  Striated muscle	Cells are cylindrical, elongated, unbranched, multinucleated Contain light dark band	Present in limbs	Allows voluntary movements
  Smooth muscle	Cells are elongated, spindle shape, have single nucleus Does not contain striation	Present in alimentary canal, iris of eye, in ureter, in bronchi of lungs	Allows involuntary movements
  Cardiac muscle	Elongated, cylindrical, branched, single nucleus	Heart	Allows continuous contraction and relaxation

• Animal Tissue – Connective Tissue:
  

  Connective tissue	Structure	Function(s)
  Blood	Contains Red Blood Corpuscles, White Blood Corpuscles and platelets	Provides essential nutrients and hormones Exchange gases and waste materials
  Bone	Bone cells are fixed in hard matrix Hard matrix made up of calcium and phosphorous	Forms body structure Site for production of white blood corpuscles
  Ligament	Strong, flexible with less matrix	Connect two or more bones with each other
  Tendons	Fibrous, strong, less flexible	Connects bones with muscles
  Cartilage	Cells are fixed in matrix Matrix is made of sugar and protein Less rigid than bone	Provides supports
  Areolar	Made up of fibroblast, collagen fibres, plasma, etc.	Binds skin with muscles Provides support to internal organs
  Adipose	Made up of fat cells	Stores energy Provides insulation to body Appears as protective covering around internal organ

• Animal Tissue – Nervous Tissue:
  • Structure:
    • Made up of nerve cells
    • Axon :Long part of nerve cells
    • Dendrites: Branched outgrowth along the nucleus
    • Brain, spinal cord, nerves are made of nervous tissue
  • Function(s): Passes signals to body parts in small time and helps to perform action instantly.