Summary

This document provides information on various body systems, including the integumentary, digestive, circulatory, excretory, and reproductive systems. It describes the organs of each system and their functions. The content is suitable for a secondary school or introductory level biology course.

Full Transcript

Integumentary System • Made up of the skin, hair and nails aswell as other glands, muscles & nerves • Protects the body, regulates body temperature, acts as a sensory receptor to internal and external stimuli, excretes waste from the body trough sweat, and absorbs vitamin D and calcium from sunlight...

Integumentary System • Made up of the skin, hair and nails aswell as other glands, muscles & nerves • Protects the body, regulates body temperature, acts as a sensory receptor to internal and external stimuli, excretes waste from the body trough sweat, and absorbs vitamin D and calcium from sunlight to nourish the body. • Skin is the largest organ in the body. • In adults our skin covers an area of 2 square meters & weighs 4.5-5kg (about 16% of our body weight) Major Organs and their Functions Mouth • To chew and grind up food, saliva also begins the chemical breakdown Esophagus • Pipe connecting mouth to stomach Stomach • Secretes an extraordinarily strong acid (pH = 2) that leads to breakdown of food • Once the food is broken down in the stomach and mixed with digestive juices, it is called chyme Pancreas • Produces the hormone insulin that regulates blood sugar levels • Also help neutralize stomach acid Liver • Produces bile, which breaks down fats in foods Gallbladder • Pouch-like organ that stores bile for future use Small Intestine • After digestion is complete, the chyme enters the small intestine where it is absorbed into the bloodstream • The chyme is propelled along by folded surfaces called villi, on the intestine Large Intestine • Removes water from the chyme and gets the waste ready for excretion Digestive system Purpose: Convert food particles into simpler micromolecules that can be absorbed into the bloodstream and used by the body Circulatory system Purpose • To deliver oxygenated blood to the various cells and organ systems in your body so they can undergo cellular respiration Major Organs and Their Functions Heart • The major muscle of the circulatory system • Pumps blood through its four chambers (two ventricles and two atria) • Pumps deoxygenated blood into the lungs, where it gets oxygenated, returned to the heart, & then pumped out through the aorta to the rest of the body • The valve regulate the flow of blood between the chambers Arteries • Carry blood away from the heart and to the major organs of the body Veins • Carry blood back to the heart away from the major organs of the body Capillaries • Small blood vessels where gas exchange occurs Blood • The cells that flow through the circulatory system • Red blood cells contain hemoglobin, an iron-rich protein that carries oxygen • White blood cells function in the immune system • Platelets help in blood clotting Spleen – helps to filter out toxins in the blood Excretory System Purpose Rid the body of wastes, including excess water and salts Major Organs and Their Functions Kidneys • Main organs of the excretory system • Waste-laden blood enters the kidney and the kidney filters out urea, excess water and other waste products, which eventually travel out of the kidney as urine • Eventually they travel through the ureter to the urinary bladder Rectum • Solid (food) waste travels out of the body through the rectum Skin • Sweat glands remove excess water and salts from the body Lungs • Expel the waste gas carbon dioxide • and digestive system Scrotum • The supporting structure for the testes, consists of loose skin and superficial facia that hangs from the root of the penis Testes • Testicles, paired oval glands in the scrotum • Testes produce sperm and male sex hormone testosterone Ducts (e.g. spermatic cord etc) • Transport, store and assist in maturation of sperm Accessory sex glands (e.g. prostate) • Secrete most of the liquid portion of semen Penis • Contains the urethra a passageway for ejaculation of semen & excretion of urine Reproductive System Male Ovaries • Produce secondary oocytes and hormones (e.g. progesterone, estraogens, inhibin & relaxin) Uterine tubes (fallopian tube) • Transport secondary oocyte to the uterus & normally where site of fertilisation occurs Uterus • Site of implantation of a fertilized egg, development of the fetus during labour etc Cervix • Narrow portion at the inferior of the uterus that opens into the vagina Vagina • Receives the penis during sex & passageway for birth Vulva • External genitals of the female Reproductive System – Female Musculoskeletal system & Nervous System to follow!

Use Quizgecko on...
Browser
Browser