Question

Need Explanation

1-Pick an epithelial tissue and connective tissue. Compare and Contrast. Where would you expect to find each and why?Need Explanation

2-Compare and contrast all 4 general tissue types?Need Explanation

Answer 1

1.let's take an example of epithelial tissue as simple squamous epithelium of skin and connective tissue as areolar connective tissue beneath it.

• The first difference is matrix: In areolar connective tissue, there are lot of spaces in the matrix whereas in case of squamous epithelium there is no space in between the cells.
• Content of the matrix: in the areolar connective tissue fibres are the main contents. in squamous epithelium of skin there is no matrix, therefore there are no fibres.
• Function: areolar connective tissue function is storing energy, structural support and filling internal spaces. Squamous epithelial tissue of skin is specialized in secretion, lines internal passages and covers exposed surfaces.
• For example in skin the epithelium of skin is squamous epithelium which contains sweat glands that secrete sweat. In areolar connective tissue that stores the energy.
• Vascularity: Epithelial tissue is not vascular. That's why skin becomes dry. It has no blood supply. Whereas connective tissue has abundant blood supply so that it provides the blood to the epithelial tissue to survive.

Both epithelium and connective tissue are closely related to each other in the location in the body since one support another. For example, skin protects the underlying areolar connective tissue from pathogens, external foreign bodies and other damages. In turn the areolar CT  provides support to the skin and blood supply to the skin tissue.

2.
1.Connective tissue: it has functions of

• structure
• support
• defence and
• transport and binding of all the other tissues together.

The connective tissue is characterized by cells and fibres. Mainly collagen and elastic fibres which are tough and loose respectively. The cells are separated by ground substance which is made up of water, fluid and a mix of proteins called matrix.
There are several different types of connective tissue:
Loose connective tissue: composed of collagen and elastic fibres. It is found in and around blood vessels and organs.
Fibrous connective tissue: it has large amount of collagen and few cells. They are found in tendons and ligaments. Cartilage is a connective tissue. It is found at the end of bones and inner septum of the nose.
Adipose connective tissue: it is body fat. It helps for insulation and storing energy.
Blood is considered as a special type of connective tissue in which cells are separated by fluid.
Bones are considered as a type of connective tissue.
Connective tissue helps to attach bone to bone and muscle to bone carries essential materials in the body in the form of blood and give shape and structure to the body and store some fat as a source of energy.

2.Epithelial tissue:
It lines cavities, cover surfaces of vessels and organs and provide several important functions.

• Protection: from sunlight and pathogens.
• Secretion: sweat, hormones and mucus.
• Absorption and exchange: for example Oxygen and Carbon dioxide exchange in the epithelial tissue of the lung.
• Sensation: touch, pressure, temperature, vibrations et cetera.

Epithelial tissues are divided into several types based on the shape and internal anatomy of the cell and number of layers:
1. Squamous: it is pavement like cells with larger width and height. It is found in blood vessels and lungs.
2. Cuboidal: width and height are same like a cube. Many times it is found in important glands.
3. Columnar: like a column, height greater than width. It is found in digestive tract and possibly in trachea. They are also classified as simple which are one layered, and stratified which are multilayered.

3.Nerve tissue:
Found in brain and spinal cord and peripheral system. Many nerve tissues are made up of nerve cells which are called neurons. Their function is to transmit electrical signal in the body through which the brain communicates with the body. A neuron has several parts. They have a cell body containing nucleus and other organelles like mitochondria and ribosomes. They also have structures called dendrites like tree branches. These dendrites receive electrical signals from other neurons. The next and neuron has axon. Nerve signal passes down and the axon and action has insulation called myelin sheath. At the end of the axon; axon terminals. They communicate with dendrites of other cells. This allows the nerve signal to pass throughout the body. There we have nervous tissue- a group of neurons working together to pass electrical signals from brain to many tissues and organs of the body.

4.Muscle tissue:
It is responsible for or movement in inside and outside of the body. In addition they help in body posture and produce heat. Muscle tissue has the ability to contract and get shorter and then relax to return to the originals size. There are three main types of muscle tissue:
1. Cardiac muscle: striated muscle with intercalated disc for fast communication between other cardiac muscle fibres. It has regularly repeated strikes which are formed by the proteins called myofilaments. It is exclusively found in heart contractile tissue and help heart pump blood.

2. Smooth muscle: it has no striations because they have no this type of myofilament arrangement. Smooth muscles are found inside the digestive tract, veins and arteries helping to move blood throughout the body. Smooth muscles are involuntary muscles and they help in movement of food and blood in the body.

3. Skeletal muscles are striated muscles which are found in relation to bone to aid in movement. Skeleton muscles are attached to the bones by a connective tissue called tendon. We have over 600 different skeletal muscles.