Human Body Structure and Function (Unit 5) - OCR PDF

Unit -- 5 ========= The Structure & Function Of The Human Body - III ================================================ **Learning Objectives** 1. Describe the structure and function of the organ systems of our body. - Excretory system - Reproductive system - Endocrine sys...

Unit -- 5 ========= The Structure & Function Of The Human Body - III ================================================ **Learning Objectives** 1. Describe the structure and function of the organ systems of our body. - Excretory system - Reproductive system - Endocrine system Unit -- 5 ========= **The Structure & Function Of The Human Body- III** **Removal Of waste products ( Excretion)** **Due to various metabolic activities in animals many harmful and unnecessary substances are produced as by-products. If these waste products are allowed to accumulate inside the body, they can be harmful to the organism. These harmful products are thrown out of the body as such or changed into harmless materials and then discharged. The process of getting rid of metabolic wastes from the body is called excretion.** **In man, the kidneys are the main excretory organs. The lungs, skin and liver also perform excretory functions.** **The lungs remove carbon dioxide and water. The skin excretes water and mineral salts through sweat. The liver removes unwanted red blood cells and excess amino acids.** **Urinary System** - **The urinary system is one of the important systems, \"which excretes the waste (end) products of metabolism that tend to change the normal internal and external environment of the cell. This is also called as excretory system.** - **The major function of the Urinary system is to remove urea from the bloodstream so that it does not accumulate in the body and become toxic. Besides removing the urea, the \"urinary System maintains the proper balance of water, salts and acids in the body fluids, salts such as sodium, potassium and some acids known as electrolytes.** - **Nephrology is the study of the \"urinary system or kidney and a specialist in this field is called a Nephrologist.** **II. Parts of Urinary System** **The Urinary System is composed of :** - **2 kidneys which secrete urine.** - **2 Ureters which convey the urine from the kidneys to the urinary bladder.** - **1 Urinary Bladder where urine collects and is temporarily stored.** - **1 Urethra through which the urine is discharged from the urinary bladder to the exterior.** **The kidneys are reddish brown, bean shaped structures located at the back of the abdominal cavity, one on each side of the vertebral column. Each kidney is made up of a large number of coiled tubes called nephrons. They carry nitrogenous waste material and excess water from the blood and form urine. From here urine passes into the urinary bladder through tubes called ureters. The urinary bladder stores urine until it is excreted through the urethra by contraction of muscles around the urinary bladder.** **The Reproductive System** **All living things reproduce to maintain continuity of its species. The reproductive organs in males and females differ in size as well as in function.** **The male sex cell the spermatozoon ( sperm cell) fuses with the female sex cell (ova ) resulting in fertilization which results in embryo.** **The male reproductive system produces a hormone called testosterone.** **Testosterone is responsible for the production of the bodily characters in the male such as beard, pubic hair, and deeper voice and proper development of male sexual organs.** **Reproductive System - Male**  **The female reproductive system consists of organs that produce ova and provide a place for the growth of the embryo (called the fetus after 2^nd^ month).** **In addition the female reproductive organs supply important hormones ( Estrogen and Progesterone )that contribute to the development of female secondary sex characteristics (Body hair, Breast development, structural changes in bones and fats.** **Reproductive System - Female** **Endocrine glands** **The characteristics of a hormone are that they are:** a. **Specific chemical messengers,** b. **Secreted by endocrine glands,** c. **Poured directly into the blood and carried by blood circulation,** d. **Act on specific tissue/ organ called target organ.** **The endocrine glands are located in different parts of the body. They are hypothalamus, pituitary (hypophysis), pineal, thyroid, parathyroid, pancreas, adrenal, testes and ovary.** **The Endocrine Glands, their hormones and functions** +-----------------------+-----------------------+-----------------------+ | **Hypothalamus** | | **Regulation of the | | | | secretion of** | | | | | | | | **hormones from | | | | pituitary** | +-----------------------+-----------------------+-----------------------+ | **Pituitary | **Growth hormone | **Development of | | (hypophysis** | Trophic hormones** | bones and muscles in | | | | the Regulation of the | | | | secretion of hormones | | | | from endocrine | | | | glands,** | | | | | | | | **adrenal, thyroid, | | | | testes and ovary.** | | | | | | | | **Regulation of | | | | function of mammary | | | | gland.** | | | | | | | | **Regulation of water | | | | and electrolyte | | | | balance.** | | | | | | | | **Regulation of the | | | | ejection of milk | | | | during lactation.** | +-----------------------+-----------------------+-----------------------+ | | | **Regulation of | | | | metabolism of** | | | | | | | | **carbohydrate, fat, | | | | and proteins** | +-----------------------+-----------------------+-----------------------+ | **Parathyroid** | **Calcitonin** | **Regulation of blood | | | | calcium and | | | | phosphate** | +-----------------------+-----------------------+-----------------------+ | **Adrenal** | **Adrenalin** | **Regulation of blood | | | | pressure, heart rate, | | | **Corticoids** | carbohydrate | | | | metabolism and | | | | mineral balance** | +-----------------------+-----------------------+-----------------------+ | **Pancreas** | **Insulin** | **Lowering of blood | | | | glucose** | | | **Glucagon** | | | | | **Increase of blood | | | | glucose** | +-----------------------+-----------------------+-----------------------+ | **Testes** | **Testosterone** | **Regulation of male | | | | accessory sex organs | | | | and secondary sexual | | | | characters like | | | | moustache, beard and | | | | voice.** | +-----------------------+-----------------------+-----------------------+ | **Ovary** | **Estrogen | **Regulation of | | | Progesterone** | female accessory sex | | | | organs and secondary | | | | sexual characters | | | | like mammary gland, | | | | hair pattern and | | | | voice. Maintenance of | | | | pregnancy.** | +-----------------------+-----------------------+-----------------------+ **\ ** **Unit 5** The Structure & Function Of the Human Body- II ============================================== **Worksheet** Fill in the blanks ------------------ 1. 2. The \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ remove carbon dioxide and water. 3. The skin excretes \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_and \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ through sweat. 4. The \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_removes unwanted red blood cells and excess amino acids. 5. 6. 7. 8. 9. **Answer the following questions.** 1. Define Excretion? 2. Name the organs of the Urinary system? 3. State the major function of the Urinary system 4. What is Nephrology? 5. What is a nephron? State its function? 6. Why do living things reproduce? 7. How is an embryo formed? 8. Give the function of the hormone Testosterone? 9. State the two major functions of the female reproductive organs? 10. Why are endocrine glands known as ductless glands? a. b. c. Thyroid d. Parathyroid e. Adrenal f. Pancreas g. Testes h. Ovary