This document provides an overview of the major organ systems in the human body. It discusses 14 different systems: nervous, lymphatic, cardiovascular, respiratory, skeletal, muscular, digestive, excretory, reproductive, endocrine, and integumentary. Each system is defined by its main functions and the major anatomical structures that comprise it. The organization of living things is also described, from atoms and molecules up through organelles, cells, tissues, organs, organ systems, and the whole organism. Homeostasis and how involuntary processes work to maintain internal stability is also summarized.

1. ANATOMY
Unit 1 Notes:
Organ Systems
& Living
Organization

2. (1) Living Organization
• All living things are made of cells and
atoms/molecules.
• Levels of Organization:
– Atoms and Molecules
– Organelles and Cells
– Tissues
– Organs
– Organ Systems
– Organism

4. (2) Atoms, Molecules & Reactions
• The basis of all living things is atoms.
• All living things contain at least the following
biological elements:
C H O N P S
• All cellular processes are driven by energy
exchange and the movement and reacting of
different molecules.

7. (3) Homeostasis
• Involuntary processes and reactions are in place to
maintain Homeostasis within cells.
• Homeostasis = Internal stability / balance.
• Examples:
– Shivering when cold.
– Production of red blood cells when oxygen drops.
– Buffering of acidic foods using bicarbonate.

8. (4) Nervous System
• Function:
– Controls all other organ systems.
– Allows you to respond to changes/stimuli.
– Allows you to maintain homeostasis.
• Made Up Of:
– Brain
– Spinal Cord
– Nerves
– Neurons

10. (5) Lymphatic System
• (A.K.A. The Immune System)
• Function:
– Protect body against harmful infectious agents +
compounds.
• Made Up Of:
– White Blood Cells
– Antibodies and Antigens
– Lymph Vessels, Nodes, and Fluid

12. (6) Cardiovascular System
• Function:
– Work with the respiratory system to circulate gases.
– Pump nutrients throughout the body to working
tissues.
• Made Up Of:
– Heart
– Blood Vessels
– Blood + Blood Cells

14. (7) Respiratory System
• Function:
– Work with the cardiovascular system to circulate gases.
– Bring oxygen into body + expel carbon dioxide.
• Made Up Of:
– Nasal Cavity
– Trachea + Bronchioles
– Lungs
– Diaphragm

16. (8) Skeletal System
• Function:
– Provide body support and mobility.
– Protect organs.
– Store minerals and growth hormones.
• Made Up Of:
– Bones
– Joints
– Cartilage

17. (9) Muscular System
• Function:
– Allow for body mobility by working with skeletal
system.
– Produce body heat.
– Allow for organ function and movement.
• Made Up Of:
– Muscle
– Ligaments + Tendons

19. (10) Digestive System
• Function:
– Break food into smaller pieces.
– Metabolize biomolecules within food.
– Absorb useful nutrients + expel waste.
• Made Up Of:
– Oral Cavity + Esophagus
– Stomach
– Small + Large Intestine
– Rectum + Anus

20. (11) Excretory System
• (A.K.A. The Urinary System)
• Function:
– Filter Blood.
– Remove excessive / harmful compounds within blood.
• Made Up Of:
– Kidneys
– Ureters
– Bladder
– Urethra

22. (12) Reproductive System
• Function:
– Pass genes on to produced offspring.
• Made Up Of:
– Male  Sperm, Testes, Penis
– Female  Eggs, Ovaries + Uterus, Vagina

24. (13) Endocrine System
• Function:
– Produce hormones.
– Control and initiate the progress of growth,
development, organ function, and reproduction.
• Made Up Of:
– Glands
– Hormones

25. (14) Integumentary System
• Function:
– Protect internal organs.
– Allow for increased manipulation.
– Increase heat barrier.
– Produce vitamins.
• Made Up Of:
– Skin
– Nails
– Hair