Tissues - Plant and Animal Tissues
Important terms and their definition:
Cell:
A cell is the basic structural and functional unit of a living organism. Example: Nerve
cell.
Tissue:
A tissue is a group of cells having a common origin, similar structure and function and
held
together by a cementing substance. Example: Connective tissue.
Organ:
Different types of tissues working together and contributing to some specific function
inside the
body constitute an organ. Example: Stomach.
Organ system:
Different organs coordinate to perform a specific life process and form an organ
system. Example:
Digestive system.
Organism:
Various organ systems working simultaneously together constitute an organism.
Example: Plants.
Epidermis:
The epidermis is the outermost protective layer of roots, stems and leaves. Outermost
layer in
older roots and stems is called cork that contains dead cells. The epidermis is covered
with a
waterproof layer called cuticle. Epidermis protects against water loss, injury or
parasitic attack.
Stomata on epidermis help diffusion, transpiration
Plant tissues are categorised broadly into three tissue systems:
1. Epidermis Cells: forming the outer surface of the leaves and of the young plant
body.
2. Vascular tissue: The primary components of vascular tissue are the xylem and
phloem.
These transport fluid and nutrients internally.
3. Ground tissue: Ground tissue is less differentiated than other tissues. Ground
tissue
manufactures nutrients by photosynthesis and stores reserve nutrients.
In animal, organs are made up of four basic types of tissues
1. epithelial tissue,
2. connective tissue,
3. muscle tissue and
4. nerve tissue.
Epithelial tissue:
Epithelial tissues form a protective layer. Epithelial tissue is made of closely packed
cells arranged
Important terms and their definition:
Cell:
A cell is the basic structural and functional unit of a living organism. Example: Nerve
cell.
Tissue:
A tissue is a group of cells having a common origin, similar structure and function and
held
together by a cementing substance. Example: Connective tissue.
Organ:
Different types of tissues working together and contributing to some specific function
inside the
body constitute an organ. Example: Stomach.
Organ system:
Different organs coordinate to perform a specific life process and form an organ
system. Example:
Digestive system.
Organism:
Various organ systems working simultaneously together constitute an organism.
Example: Plants.
Epidermis:
The epidermis is the outermost protective layer of roots, stems and leaves. Outermost
layer in
older roots and stems is called cork that contains dead cells. The epidermis is covered
with a
waterproof layer called cuticle. Epidermis protects against water loss, injury or
parasitic attack.
Stomata on epidermis help diffusion, transpiration
Plant tissues are categorised broadly into three tissue systems:
1. Epidermis Cells: forming the outer surface of the leaves and of the young plant
body.
2. Vascular tissue: The primary components of vascular tissue are the xylem and
phloem.
These transport fluid and nutrients internally.
3. Ground tissue: Ground tissue is less differentiated than other tissues. Ground
tissue
manufactures nutrients by photosynthesis and stores reserve nutrients.
In animal, organs are made up of four basic types of tissues
1. epithelial tissue,
2. connective tissue,
3. muscle tissue and
4. nerve tissue.
Epithelial tissue:
Epithelial tissues form a protective layer. Epithelial tissue is made of closely packed
cells arranged
