Vocabulary: The Skin

Transcription

1 Vocabulary: The Skin organ a part of the body which has a special function sensation feeling e.g. numbness, pain, tingling shivering shaking of the body when a person is very cold sweat clear liquid which comes out of the skin to cool it pore tiny opening of the sweat gland onto the skin thickness the measurement of how deep something is touch feel with the fingertips ultraviolet the light rays of sunlight

2 Skin Anatomy Label the parts of the skin. Use the diagram above to help you.

3 Skin Facts The skin is the largest organ of the body. It covers about 2 square metres and weighs about 16 per cent of the total weight of the body. The thickness of skin is different around the body. The thinnest skin of around 0.5 mm is found on the eyelids while the thickest skin of about 4mm is on the palms of the hands and the soles of the feet. The skin performs several roles in the body, including: * protecting the body from infection, if there are no breaks in the skin. * keeping fluids in the body, e.g. water and blood * excreting sweat through the pores of the skin to cool the body * protecting the body from harmful rays of the sun. The skin has three layers: The epidermis (the outermost layer) is the waterproof layer which forms a protective barrier. Special cells in the epidermis produce melanin which protects the body from ultraviolet rays. The dermis (the middle layer) is the layer which contains hair follicles, sweat glands and nerve endings for touch.

4 The subcutaneous (deepest layer) is the layer which is responsible for fat storage and also contains large blood vessels and nerves. Also called the hypodermis. Hair and Nails Vocabulary arrector pili small muscles attached to hair follicles which make the hairs stand up cuticle hardened skin at the base of fingernails and toenails goosebumps standing up of the hairs of the skin and small lumps on the skin when a person feels cold hair follicle small tube which contains the root of a hair hair shaft part of the hair that grows out of the scalp keratin tough type of protein which makes up hair and nails pigment substance which colours the hair scalp the skin on the skull sebaceous describing sebum or oil sebum oily substance from the sebaceous gland Medical Terms: Nails Hair and Nails Hair under the skin is called the hair follicle and called the hair shaft above the scalp. The hair follicle is fed by small capillaries in the dermis layer of the skin. The inner part of the hair follicle ends under the opening of a sebaceous gland. Sebaceous glands produce sebum or oil which helps to prevent the skin and hair from drying out.

5 A muscle called the arrector pili muscle attaches to the outside of the hair follicle below the sebaceous gland. When a person is cold, the muscle contracts and causes the hair follicle to stand up. Small raised lumps called 'goosebumps' appear on the skin at the same time. The hair shaft is the part of the hair which is above the scalp. The hair shaft is made of a hard protein called keratin. The inner layers of the hair shaft contain a pigment called melanin which gives the hair its colour. The fingernails are also made of keratin. The hard covering protects the fingertips and improves the ability to feel objects when they are touched by the fingers. Label the parts of the nail.

6 Medical Terms: Diseases and Conditions of the Hair and Nails Vocabulary dermatitis hyperhidrosis keratosis pilonidal abscess seborrhoea tinea unguium Medical Terminology: Suffixes There are several suffixes or word endings which you'll often see to describe diseases or conditions. Common suffixes are: -itis -osis -rrhoea inflammation often because of an infection abnormal increase or abnormal condition flow or discharge e.g. of fluids The suffixes are added to word parts which describe the hair and nails. For example, dermatitis hyperhidrosis keratoses solar keratosis pilonidal abscess seborrhoea the inflammation of the skin causing itchiness and redness Sometimes dermatitis is caused by an allergy excessive perspiration, usually on the palms of the hands, the soles of the feet and in the armpits abnormal growths of hard skin or 'sun spot' is hardened skin caused by staying in the sun for long periods of time forms when a hair grows back into the skin and becomes infected excess sebum on the scalp which causes crusty scales to form. It is called 'cradle cap' when it forms on a baby's head

7 tinea unguium fungal infection of the nails. Also called athlete s foot Nail Diseases

8