Human Body Systems

Human Body Systems RHS Biology

Respiratory System • Function: Breathing brings air into the lungs and removes waste gases to constantly supply the blood with Oxygen and remove Carbon Dioxide • Cellular respiration converts oxygen and glucose to carbon dioxide, water and energy

Respiratory system • Upper and Lower respiratory tracts • Gas exchange occurs through the walls of the air sacs of the lungs. • The epiglottis covers the trachea when you swallow. • Gas exchange occurs in the alveoli

Fact • The surface area of the alveoli in your lungs is about 70 square meters, or about the same as three lanes of a bowling alley.

Diseases of respiratory system • Lung Cancer -3rd leading cause of death in men and women in the U.S. • Emphysema ( causes alveoli to enlarge) • Asthma (lung disorder)

Cardiovascular System • Blood vessels transport blood which carries: Oxygen, Carbon Dioxide, Nutrients and waste. • Coronary circulation is the flow of blood to and from the tissues of the heart. • Pulmonary circulation is the flow of blood through the heart, to the lungs, and back to the heart. (Right side of the heart) Heart to lungs. • Oxygen rich blood is moved to all tissues and organs of the body, and is called Systemic circulation. (Left side of the heart) Heart to the rest of the body.

Organs of the circulatory system • Heart • Veins • Arteries • Capillaries • Blood - Tissue

Heart • Made of cardiac muscle tissue • Has 4 compartments called chambers: two upper are atriums, two lower are ventricles. • The Heart has arteries and veins just like any other muscle • The Septum divides the right and left side of the heart.

Fact • Your heart beats 60-70 times per minute. Each time it pumps 60 mL of blood. How many mL’s in 24 hours. • 5,184,000 mL’s or • 5,184 liter bottles.

Heart • When these arteries are blocked, it starves the heart of oxygen and nutrients, resulting in a heart attack • Fatty build up on the walls of arteries is atherosclerosis.

Veins • Veins carry blood back to the heart. • Veins have valves that prevent blood from flowing backward in the heart.

Arteries • Carry blood away from your heart • Have thick, elastic walls made of tissue and smooth muscle

Capillaries • Microscopic blood vessels. • Walls are only one cell thick • Bloodshot eyes • Nutrients and oxygen diffuse from body cells into capillaries

Blood pressure • The force of the blood against the walls of your blood vessels. • Measured in two numbers: • Systolic is the first number and measures your heart pumping. • Diastolic is the second number and measures pressure that occurs as the ventricles fill with blood before they contract again.

Blood • Carries oxygen from lungs to the body • Takes carbon dioxide away from the body • Carries waste products to the kidneys • Transports nutrients • Cells in blood fight infections

Blood • Made up of plasma (55%), mostly water. • Platelets ;help with clotting • Red blood cells: made at rate of 2-3 million per second. Transport Oxygen and contain hemoglobin. • White: help fight bacteria, viruses, etc

Blood Types • 4 types • A, B, AB, O • Types A, B, AB have antigens coating their surface. Rh factor • Wrong type of blood may kill you • Type “O” is universal

Excretory System • Includes many systems such as digestive, respiratory, skin and urinary system. • Each gets rid of waste in its own way.

Excretory (urinary) System • Regulates water, electrolyte and acid-base balance in the blood. • Water and salts in • Excess water, metabolic wastes and salts out. • Controls blood volume ( blood pressure) • Works in conjunction with the hypothalamus to balance fluid levels in blood

Organs of Urinary System • Kidneys are bean shaped organs • Located at back of abdomen at waist level • The Kidney filters blood of waste products, and creates a waste product called urine

Kidneys • All of your blood is filtered through your kidneys in about 5 minutes. • Connected to the bladder through two ducts called the ureters • Drains urine into your bladder • Removal of waste from the blood using a machine is called dialysis.

Bladder • The Bladder is where urine is held until you release it. • The Bladder is an elastic, muscular organ that can stretch to hold .5 liter of urine. • The Avg. human produces about 1 liter of urine daily.

Digestive System • Breaks down food into absorbable units that enter the blood for distribution to body cells. • Mechanical digestion is the physical breakdown of pieces of food into smaller pieces. • Chemical digestion is the breakdown of food into particles that can be absorbed. • Intestines absorb water. • Water and undigested food are eliminated as feces.

Respiratory System • Part of excretory system • Oxygen in • Carbon dioxide and water out.

Skeletal System • Provides a framework that muscles use to cause movement. • Protects organs, gives shape and supports the body • Produces red blood cells • Stores minerals • At birth you have approx. 300 bones • As an adult 206 bones

Skeletal System • The Axial Skeleton contains the skull, rib cage and the vertebral column. The Appendicular skeleton contains the arms/legs, shoulders, and pelvis.

Skeletal System • Most of the bone mass is made up of calcium and phosphorus • The skeleton of an embryo is almost entirely cartilage. • Ossification is the process of replacing cartilage with bone. • A joint is a place where two bones meet. • Ligaments hold bones together at joints.

Muscular System • Over 600 muscles in your body • Controls movement • Skeletal - Voluntary muscles: you choose to move them – (Striated) • Cardiac (heart) Involuntary • Smooth Muscles - Involuntary

Muscles • 3 types • Skeletal/Striated: attached to bones to help you move Voluntary • Cardiac: (heart)- Involuntary • Smooth: intestines, bladder, blood vessels, internal organs Involuntary

Integumentary System • Functions: 1. Serves as a barrier against infection/ injury 2. Regulates body temp. by blood vessels in the dermis contracting/expanding. 3. Removes waste products. 4. Protects against UV rays.

Integumentary System • Body’s first line of defense • Hair, Skin and Nails • Synthesizes Vitamin D • Detects pain and pressure • Contains Sweat and Oil glands

Nervous System • Responds to stimuli to maintain homeostasis • Central nervous system consists of your brain and spinal cord. • Peripheral nervous system is all the nerves other than the CNS

Brain • Cerebrum – Controls voluntary activities • Cerebellum – Coordinates and balances the actions of muscles. • Brain stem – Regulates the flow of information. • Thalamus – Receives and relays messages from the sense organs. • Hypothalamus – Controls hunger, thirst, fatigue, anger, and body temperature.

Brain • Cerebellum • Responsible for coordinating your muscles and balance • Keeps you from falling down when you walk

Brain • Brain stem • Controls involuntary actions such as breathing and heartbeat

Brain • Your brain contains appox. 100 billion neurons • Cerebrum: interprets input from senses • Controls movement • Responsible for learning and memory

Endocrine • Each gland produces a different hormone responsible for a different task. • Endocrine releases secretions into the blood. • Adrenal glands produce adrenaline • Testes produce testosterone • Ovaries produce estrogen

Endocrine System • The Endocrine system produces chemicals that control many of the body’s daily activities, as well as, long term changes such as growth and development through the release of hormones.

Endocrine • Made up of glands • Glands secrete hormones that regulate the body. • Hormones are chemicals that turn off, turn on or speed up, or slow down the activities of organs and tissues. (Growth, Reproduction, Metabolism)

Glands of the Endocrine System • Pituitary – regulates body functions • Hypothalamus – Controls the secretions of the Pituitary. • Thyroid – Helps regulate metabolism. • Parathyroid – Regulates Calcium levels • Adrenal – Helps the body deal with stress. • Pancreas – Stabilizes blood glucose. • Reproductive – Production of gametes and secretes sex hormones. Testes/Ovaries

Reproductive System • The ovaries are the female gonads and secrete estrogen • The male gonads are the testes and secrete testosterone • Hormones determine if the embryo will be male or female.

Reproduction • The testes remain outside of the body cavity for a lower temperature for better sperm development. • The ovaries usually produce one mature ovum each month.

Fertilization and Development • The process of a sperm and an egg is called fertilization. • A fertilized egg is called a zygote. • After 8 weeks of development an embryo is called a fetus. • Most of the major organs and tissues are fully formed by the end of the 3 months of development. • Adults reach their highest levels of physical strength and development between the ages of 25-35.

Immune SystemMain defense against pathogens • The Body has 3 lines of defense: skin (sweat/tears), breathing passages (mucus), mouth and stomach. • Pathogens land on skin and most are destroyed by chemicals in oil and sweat.

Immune • Pathogens get through skin usually only when there is break in skin: a scab quickly forms to protect pathway. • Phagocytes (white blood cells) engulf and destroy pathogens. • Fever kills many pathogens/speeds up the action of white blood cells. • Antibodies are proteins that help destroy pathogens.

Immune • Antigens trigger the immune response in the body. (Viruses, bacteria, other pathogens) • Breathing: pathogens enter, but are trapped and destroyed by a mucus layer. Cilia in the nose move accumulated material out.

Immune • Pathogens found in food are destroyed first by saliva, and then, by powerful acids in stomach

“T” Cells & “B” Cells • T- cells identify pathogens by identifying a chemical marker on the pathogen called an antigen • Some T cells attack pathogen; others activate B cells.

Immune • B-cells are called lymphocytes and produce proteins called antibodies. When antibodies bind to the antigens on a pathogen, they mark it for destruction by phagocytes.

Vaccinations for Immunity • Vaccinations are injections of a weakened or mild form of a pathogen to produce immunity. • Active/Passive Immunity can result from vaccinations. Active lasts for life, Passive is due to antibiotics for a short time.

Human Body Systems