Section 28-1 “Introduction to Physiology”

KEY CONCEPT The human body and other organisms have five levels of organization.

A. Levels of Structural Organization Atom Molecule Cell Tissue Organ Organ System Organism

carbon Molecule phospholipid Cell nerve cell Tissue nervous tissue Examples: Atom Molecule Cell Tissue Organ Organ System Organism carbon phospholipid nerve cell nervous tissue brain nervous system human

1. Atoms combine to form molecules Ex: sugar, water, protein Atoms Molecule

2. Molecules form cells Cell Molecules

a. Specialized cells develop from a single zygote. Organisms are made up of specialized cells. red blood cell nerve cell

Stem cells develop in two stages. Zygotes first divide into embryonic stem cells. Stem cells develop in two stages. determination, or committing to become one cell type differentiation, or acquiring specialized structures and functions

3. Cells form tissues Similar cells with a common function form tissues There are 4 basic tissue types: Epithelial Nervous Muscular Connective

Specialized cells perform specific tasks. 4. Specialized cells function together in tissues, organs, organ systems, and the whole organism. Specialized cells perform specific tasks. Tissues are groups of similar cells working together. tissue cell epithelial tissue connective tissue muscle tissue nervous tissue

5. Tissues form organs Two or more tissue types form an organ An organ is a structure that performs a specific function for the body

6. Organs form Organ Systems A group of organs which work together for a common purpose is an organ system Put all the organ systems together and you create an ORGANism Nervous System Brain, Spinal Cord, etc.

B. Body Systems 1. Integumentary System Skin is the only organ Protects from injury Regulates body temperature Receptors for temperature, pain, and pressure

2. Skeletal System Bones, cartilage, ligaments, and joints Supports body Protection Storage for minerals (calcium) Hematopoiesis (formation of blood cells) takes place in the cavities of skeleton

3. Muscular System Muscles contract (shorten) to cause movement Skeletal muscles are large, fleshy, and attached to bone Skeletal muscles – not cardiac or smooth muscle

Brain, spinal cord, nerves, & sensory receptors 4. Nervous System Brain, spinal cord, nerves, & sensory receptors Responds to irritants or stimuli Sensory organs detect change Then they send nerve impulses to the Central Nervous System (brain and spinal cord) Then the CNS responds The CNS assesses the info. and respond by activating the appropriate body muscles or glands

Releases hormones to control: Growth Reproduction Food use 5. Endocrine System Releases hormones to control: Growth Reproduction Food use Slower than CNS Hormones are released by endocrine glands and travel through the blood to organs

Cardiovascular System: Heart and blood vessels Transport oxygen, etc. 6. Circulatory System Made of 2 organ systems: Cardiovascular System: Heart and blood vessels Transport oxygen, etc. Lymphatic System: Cleanses blood, immunity Textbook displays these as 2 different systems

Nasal passages, pharynx, larynx, trachea, bronchi, lungs 7. Respiratory System Nasal passages, pharynx, larynx, trachea, bronchi, lungs Supplies body with oxygen Removes carbon dioxide Tiny air sacs called alveoli exchange oxygen with the blood

Breaks down food and delivers nutrients to blood for cells in the body 8. Digestive System Mouth, oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, rectum Breaks down food and delivers nutrients to blood for cells in the body Bile breaks down fat

9. Urinary System Regulates: Water balance Salt balance Kidneys, ureters, bladder, and urethra Removes Nitrogen-containing wastes from the blood and flushes them from the body in urine Regulates: Water balance Salt balance pH (acid-base) balance Urea & uric acid result from the breakdown of proteins and nucleic acids by body cells

10. Reproductive System Functions to produce offspring Male testes produce sperm Male Structures: scrotum, penis, accessory glands, duct system Female ovaries produce eggs Female structures: uterine tubes, vagina, uterus (where fetus develops)

All of the organ systems form the organism

Activity – Due end of the period Thursday. You are going to create a mini poster with your table partner. You will make them for 2 organ systems. Layout of Poster (Follow this layout, or lose points…) Major Organ System: (Name organ here) Major Tissues & Organs Primary Function ____________________ ______________ *Must have 2-3 pictures*