Question

what are the functions,features, and locations of epithelial, connective, muscular, and nervous tissue?

Answer 1

The tissues of the body are classified according to the size, shape and functions of the cells. There are four main types of tissues. They are:

• Epithelial tissue
• Connective tissue
• Muscular tissue
• Nervous tissue

EPITHELIAL TISSUE :-

This group of tissues are found covering the body and lining cavities and tubes. It is also found in the glands. The functions include:

• Protection of underlying structures from, for example dehydration, chemical and mechanical damage.
• Secretion
• Absorption
• Diffusion
• Movement

The epithelial tissue is again classified into:

1. SIMPLE (single layer of cells) --- squamous epithelium, cuboidal epithelium, columnar epithelium, ciliated epithelium.

2. STRATIFIED (several layers of cells) ---- stratified squamous ( keratinized and nonkeratinized) and transitional epithelium.

CONNECTIVE TISSUE : -

It is the most abundant tissue in the body. The cells forming the connective tissues are more widely separated from each other than those forming the epithelium, and intercellular substance (matrix) is present in considerably larger amounts.

Major functions of connective tissue are:

• binding and structural support
• protection
• transport
• insulation

The different types of cell involved in connective tissue include:

• fibroblasts
• fat cells
• macrophages
• leukocytes
• mast cells

The sub division of connective tissue are :

1. Loose connective tissue
2. Dense connective tissue ----- Fibrous and elastic
3. Adipose tissue ---- white adipose tissue and brown adipose tissue
4. Blood
5. Lymphoid tissue
6. Cartilage ---- hyaline cartilage, fibrocartilage and Elastic cartilage
7. Bone ---- compact bone and spongy bone .

MUSCULAR TISSUE :-

There are three types of muscle tissue, which consists of specialized contractile cells:

1. skeletal muscle -- It is called as skeletal, striated, striped or voluntary muscle. It is called voluntary because contraction is under conscious control.
2. smooth muscle  ---- It is described as non-striated or involuntary. It is not under conscious control. It is found in the walls of hollow organs. regulating the diameter of blood vessels and parts of the respiratory tract , propelling contents of the ureters, ducts of glands and alimentary tract , expelling contents of the urinary bladder and uterus.
3. cardiac muscle --- This type of muscle tissue is found exclusively in the wall of the heart. It is not under conscious control. It helps in the contractions of myocardium.

NERVOUS TISSUE :-

Two types of tissue are found in the nervous system:

• excitable cells — these are called neurons and they initiate, receive, conduct and transmit information
• non-excitable cells — these support the neurons.