All living organism is made up of the basic unit called the cell. Generally, living organisms fall into three categories; animals, plants, and microbes (microorganism). According to the Cell Theory, a cell is the structural and functional unit of all these organisms. Unlike unicellular microbes, animals and plants show the higher level of organization. They have complex body structure. Cells are grouped together to form tissues in animals and plants. These tissues vary in their structure, function, and origin. Difference between an animal tissue and a plant tissue are discussed below.
Animal body is made of four different types of tissues.
- Epithelial Tissue
- Muscle Tissue
- Connective Tissue
- Nerve Tissue
Epithelial Tissue: All organs in the body are lined with a group of tissues called epithelial tissues. They cover the surface of all internal as well as external organs. There are four types of epithelial tissues: Squamous epithelium, Stratified epithelium, Cuboidal epithelium and Columnar epithelium. They may be cuboidal, columnar or even flat. The main functions of these tissues involve protection, secretion, absorption, sensation etc..
Muscle Tissue: This type of tissue forms three types of muscles, namely skeletal (striated or voluntary) muscle, smooth (non-striated or involuntary) muscle and cardiac (heart) muscle. They help in movement by contraction and relaxation of muscles.
Connective Tissue: As the name suggests, they connect the different tissues, organs, and parts of the body. Different types of connective tissues are Areolar tissue, Adipose tissue (fat), Blood, Lymph, Bone, and Cartilage. They connect and support organs and also transport substances between organs.
Nervous Tissue: These tissues are made up of specialized cells called nerve cells (neurons). They conduct and transmit electrochemical impulses between neurons.
Plant structure is different from the animal skeletal structure. A plant tissue is different from those in animals. Plant tissues are basically divided into two: Meristematic tissue and Permanent tissue.
Meristematic tissue: These tissues comprise of cells which have the dividing capacity. They are immature and help plants to divide continuously throughout the life. Depending on the site of location, it is of three types. Apical, lateral and intercalary meristems. These meristems enlarge the cell and increase the length and width of the stem, roots, and leaves.
Permanent tissue: Permanent tissues are derivative of meristematic tissue. They don’t have the dividing capability but aid in other functions like conduction of substances, storage of food etc. Two types of permanent tissues are found in plants i.e. simple and complex permanent tissue. Simple permanent tissues include parenchyma, collenchyma, and sclerenchyma while complex tissues are xylem and phloem.