Human Body Notes

An Overview of Anatomy and Physiology Anatomy – the study of the structure and shape of the body and body parts and their relationship to one another. Physiology – study of how the body & its parts work or function

Levels of Organization ATOMCELLTISSUEORGAN ORGAN SYSTEMORGANISM

ORGAN SYSTEM OVERVIEW SYSTEMS HAVE A PRIMARY FUNCTION CLOSELY INTERRELATED SYSTEMS INCLUDE: INTEGUMENTARY, IMMUNE, SKELETAL, MUSCULAR, NERVOUS, ENDOCRINE, CIRCULATORY, LYMPHATIC, RESPIRATORY, DIGESTIVE, URINARY, REPRODUCTIVE

Skeletal System Bones/cartilage/joints/ligaments/tendons Supports (provides framework) Protection Produces Blood cells Mineral Storage

Muscular System Muscles Skeletal - Allows locomotion Cardiac – Heart Muscle Smooth – surrounds blood vessels and hollow organs

Cardiovascular System Heart, Blood vessels and Blood Transportation of blood which carries oxygen, CO2, nutrients, and waste White blood cells and chemicals in blood protect body from invaders

Respiratory System Nasal passages, pharynx, larynx, trachea, bronchi, lungs Exchange of gases – CO2 and O2

Smoker’s Lung

Digestive System Mouth, esophagus, stomach, small and large intestines and rectum, anus Breaks down ingested food for absorption, eliminates undigested foods as feces Liver secretes bile – breaks down fats Pancreas secretes insulin – control sugar levels

Excretory (Urinary) System Kidneys, ureters, bladder, urethra Eliminates urea (nitrogen containing waste) from breakdown of proteins Eliminates urine Regulates water and salt balance

Integumentary System Skin Waterproofs body Cushion, protects deeper tissue from injury Barrier from invaders Excretes salts and urea via perspiration Regulation body temperature

Lymphatic System Lymph and Lymph vessels Cleanse blood and house white blood cells Returns leaked fluid to blood

Immune System Protection against viruses and bacteria Pathogen is a disease causing agent White blood cells are primary fighting cells

What is Immunity? Nonspecific Defense– the fortress walls of the immune system—keeps everything out and guard against all infections Specific Defense– security guards – track down harmful pathogens that have managed to break through the body’s nonspecific defense

Nonspecific Defense First Line – Skin Second Line - Inflammatory Response due to tissue damage caused by injury or infection – Fever

Specialized Immune System Antibodies are special proteins that help destroy disease-causing organisms. Antigens are substances that trigger an immune response

Specific Defense Immune Response - If a pathogen gets past nonspecific, the immune system reacts with a series of events that attack disease causing agent. Antibody is protein that helps destroy pathogen. Antibody binds to the surfaces of bacteria, they mark the cells.

Passive Immunity Passive immunity only last a short time. The antibodies are borrowed. Maternal immunity – baby get passive immunity from mother’s milk Travelers given antibodies against tropical diseases.

Active Immunity Vaccination The injection of a weakened or mild form of a pathogen to produce immunity is known as a vaccination. This is known as active immunity. Weakened viruses are used to stimulate your body to make antibodies. Your body is then prepared to fight if virus enter your body

Nervous System Brain, Nerves, Spinal Cord Responds to internal and external stimuli Stimuli is any change in the environment Central Nervous System and Peripheral Nervous System

Basic Part of the Nervous System Neuron – messages are picked up from the environment or other neurons

Synapse The gap between the axon of one neuron and the dendrites of another. Neurotransmitter – a chemical that carries messages between different nerve cells or between nerve cells and muscles.

Three types of Neurons Sensory Neurons – Pick up stimulus from the outside environment or from inside the body. These are found in organs called receptors. (skin, eyes ears, nose, tongue, glands) They transmit the message to the interneuron. Interneurons – receives message from sensory neuron and interpret them. They then decide where they should be sent. Motor Neuron – Receives messages from interneurons and sends them to organs called effectors (muscles and glands)

Reflex Arc

Endocrine System Glands and hormones Secretion of hormones which regulate growth, reproduction and metabolism Metabolism is the chemical reactions that occur within body cells

Feedback Mechanisms Endocrine system is regulated by feedback mechanisms that function to maintain homeostasis Examples – maintain water balance, insulin levels, metabolism through thyroxin.

Reproductive System Male – testes, scrotum, penis Produce sperm and secondary sex characteristics (testosterone) Female – ovaries, fallopian tubes (oviducts) uterus, vagina Produce egg and secondary sex characteristics (estrogen)

Development of Offspring Gametes – reproductive cells (egg and sperm) Fertilization occurs in the oviduct 1st 8 weeks - Embryo Development of fetus in uterus