Pages 5 (1255 words)
Question # 1.What are the negative feedback mechanisms and why are they important to health. Answer: The negative feedback mechanisms of a living organism are the mechanisms that reduce or suppress the original stimulus, given the effector’s output.
Question #7: What changes occur to the Integumentary System during aging? How does this affect the health of elderly people? Answer: The term integumentary system is used to describe an organ that consist of the skin, its derivatives (sweat and oil glands), nails and hair. The basic function of this system is the protection. The skin consists of epidermis and dermis. Epidermis consists of following three types of cells: keratinocytes, melanocytes, Merkel cells and Algerians cells) and dermis. These cells are arranged in different layers namely Stratum basale, Stratum spinosum, Stratum granulasum, Stratum lucidum and Stratum Corneum. The basic functions of these cells are to produce keratin (Keratinocytes) and melanin (Melanocytes), to activate the immune system as macrophages (Langerhans cells) and to act as sensory receptors. Demies consists of papillary and reticular layers and are richly supplied with nerves (sensory receptors), blood vessels, lymphatic vessels, sweat and sebaceous glands derived from the epidermis. Also the accessory structures include hair, nail and glands. During aging integumentary system disorder like acne, athletes foot, boils, fever blisters, impetigo, warts, alopecia, burns, calluses (corns), cancers, dandruff, eczema and moles psoriasis become more obvious as after fifty years, wrinkles and sagging of the skin becomes more noticeable. Some of them are infectious (contagious) or non- infectious and are caused by bacteria or virus or fungus. ...