Section 2 Task 2

Stomach• The stomach has 3 layers of non-striated

muscle in its wall and an inner lining of columnar epithelium with goblet cells.

• Areolar tissue connects the stomach lining with the muscular coat.

Function

• The function of the stomach is to mix chewed food with hydrochloric acid.

• This acid is an ideal environment for digestive enzymes to work at their optimum.

Role of stomach muscles in digestion

• The muscle tissues help to churn up food and is involved in the process of peristalsis.

• Peristalsis = a wave like muscle contraction moving food along the digestive tract.

• Muscle tissues also responsible for controlling the opening and the closing of the sphincter.

Goblet cells

• Goblet cells or columnar epithelial cells produce acid, digestive enzymes such as amylase, protease and lipase.

• They also produce mucus.

Areolar tissue

• Areolar tissue is responsible for holding the layers of the stomach together, similar to plywood, hence the thinness of the structure.

Skin

• It protects the body from exposure to micro-organisms and chemicals which could cause harm to the body.

• It also regulates body temperature.

5 Main layers of tissues

•Muscle tissue• Adipose tissue• Epithelial tissue• Areolar tissue• Nervous tissue

• Muscle tissue pull down the hair on our skin which acts as an insulating mechanism.

• When erect, the hair traps a layer of air for insulation.

• Adipose tissue acts as an insulator and a shock absorber, it protects vital organs.

• Stratified epithelium acts as a protective barrier and has the ability to repair the skin if it is damaged.

• Cuboidal epithelium are located by the sweat ducts and has the function of cooling the skin down.

• Areolar tissue joins the skin to the muscle layer beneath and reinforces the skin structure.

• Nervous tissue – relay nerve impulses generated from the specialised skin sensory receptors for heat, touch, pain and pressure and in turn informing the brain of any environmental changes.