Organ Systems Overview

Nervous System:
- Central Nervous System (CNS): brain and spinal cord
- Peripheral Nervous System (PNS): nerves and ganglia
- Functions: control, integration, and coordination of body functions
Circulatory System:
- Heart: pumps blood throughout the body
- Blood vessels: arteries, veins, and capillaries
- Functions: transport oxygen and nutrients, remove waste
Respiratory System:
- Lungs: exchange oxygen and carbon dioxide
- Trachea, bronchi, and bronchioles: airways
- Functions: bring oxygen into the body, remove carbon dioxide
Digestive System:
- Mouth, esophagus, stomach, small intestine, and large intestine
- Functions: break down and absorb nutrients
Endocrine System:
- Glands: produce and secrete hormones
- Functions: regulate growth, development, and metabolism
Integumentary System:
- Skin, hair, nails, and associated glands
- Functions: protect the body, regulate body temperature
Muscular System:
- Skeletal muscles: voluntary movement
- Smooth muscles: involuntary movement
- Cardiac muscles: heart function
Skeletal System:
- Bones: support and protect the body
- Joints: allow for movement
Urinary System:
- Kidneys: filter waste and excess fluids
- Ureters, bladder, and urethra: store and eliminate urine
Immune System:
- Protects the body against pathogens and disease
- Includes lymphoid organs, tissues, and cells

Cell Membrane:
- Phospholipid bilayer with embedded proteins
- Regulates what enters and leaves the cell
Cytoplasm:
- Gel-like substance inside the cell membrane
- Site of many cellular activities
Nucleus:
- Controls cell growth, division, and function
- Contains DNA
Mitochondria:
- Generate energy for the cell through cellular respiration
Endoplasmic Reticulum (ER):
- Synthesizes and transports proteins and lipids
- Rough ER: has ribosomes attached
- Smooth ER: involved in lipid synthesis and detoxification
Ribosomes:
- Site of protein synthesis
- Found in the cytoplasm and attached to the ER
Lysosomes:
- Contain digestive enzymes
- Break down and recycle cellular waste and foreign substances

Homeostasis:
- The body's ability to maintain a stable internal environment
- Regulates temperature, pH, and other bodily functions
Feedback Mechanisms:
- Negative feedback: reverses a change
- Positive feedback: amplifies a change
Reflexes:
- Automatic responses to stimuli
- Involves the nervous system
Acid-Base Balance:
- The body's ability to maintain a stable pH
- Regulated by the lungs, kidneys, and buffers

Nervous System: Controls, integrates, and coordinates body functions through the Central Nervous System (CNS) and Peripheral Nervous System (PNS).
Circulatory System: Transports oxygen and nutrients, and removes waste through the heart, blood vessels, and blood.
Respiratory System: Brings oxygen into the body and removes carbon dioxide through the lungs, trachea, bronchi, and bronchioles.
Digestive System: Breaks down and absorbs nutrients through the mouth, esophagus, stomach, small intestine, and large intestine.
Endocrine System: Regulates growth, development, and metabolism through glands that produce and secrete hormones.
Integumentary System: Protects the body and regulates body temperature through the skin, hair, nails, and associated glands.
Muscular System: Facilitates movement through skeletal muscles (voluntary), smooth muscles (involuntary), and cardiac muscles (heart function).
Skeletal System: Supports and protects the body through bones and allows for movement through joints.
Urinary System: Filters waste and excess fluids through the kidneys and stores and eliminates urine through the ureters, bladder, and urethra.
Immune System: Protects the body against pathogens and disease through lymphoid organs, tissues, and cells.

Cell Membrane: A phospholipid bilayer with embedded proteins that regulates what enters and leaves the cell.
Cytoplasm: A gel-like substance inside the cell membrane where many cellular activities take place.
Nucleus: Controls cell growth, division, and function, and contains DNA.
Mitochondria: Generates energy for the cell through cellular respiration.
Endoplasmic Reticulum (ER): Synthesizes and transports proteins and lipids, with rough ER having ribosomes attached and smooth ER involved in lipid synthesis and detoxification.
Ribosomes: The site of protein synthesis, found in the cytoplasm and attached to the ER.
Lysosomes: Contain digestive enzymes and break down and recycle cellular waste and foreign substances.

Homeostasis: The body's ability to maintain a stable internal environment, regulating temperature, pH, and other bodily functions.
Feedback Mechanisms: Negative feedback reverses a change, while positive feedback amplifies a change.
Reflexes: Automatic responses to stimuli that involve the nervous system.
Acid-Base Balance: The body's ability to maintain a stable pH, regulated by the lungs, kidneys, and buffers.