Describe the functions of the parts of a mammalian skin. 20 Marks

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  • Cornified layer; for protecting the skin; against mechanical damage; bacterial infection; water loss;
  • Granular layer; cells divide to give rise to cornified layer;
  • Malphighian layer; cells divide to give rise to granular layer; It contains melanin which protects the skin against UV light;
  • Sebaceous gland; -produce oily secretion which is antiseptic; and protects the body against micro-organisms
  • Sebum makes skin supple; and waterproof. This protects the skin from drying and cracking due to desiccation;
  • Blood vessels; bring oxygen; and food; to the skin and remove waste products; from the
  • skin and control body temperature;
  • Nerve ending; enable mammals to detect changes in the external environment;
  • Sweat glands; produce sweat; and when sweat evaporates brings cooling of the body; Sweat removes waste products from the body;
  • Skin has hair or fur which maintains body temperature’
  • Subcutaneous fat; in the dermis insulates the body against heat loss or gain;
20 MARKS
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