Chapter 1: Key Concepts and Body Systems

Anatomy

The study of the structure of body parts and their relationships to one another.

Physiology

The study of the function of the body's structural machinery.

Levels of Organization

The hierarchy of complex biological structures and systems that define life, from atoms to organisms.

Atom

Matter is composed of atoms, which are composed of subatomic particles.

Molecule

Atoms join to form molecules.

Macromolecule

Small molecules may combine to form larger macromolecules.

Organelle

Organelles consist of aggregates of interacting macromolecules, including proteins, carbohydrates, lipids, and nucleic acids.

Cell

Cells are composed of organelles; the basic unit of structure and function of the body.

Tissue

Tissues are specialized cells that assemble into layers or masses that have special functions.

Organ

Organs are complex structures with specialized functions formed by groups of different tissues.

Organ system

Organ systems are groups of organs that function closely together.

Organism

Organisms are interacting organ systems.

Movement

Changes in position of the body or of a body part; motion of an internal organ.

Responsiveness

Reaction to a change inside or outside the body.

Growth

Increase in body size without change in shape.

Reproduction

Production of new organisms and new cells.

Respiration

Obtaining oxygen, removing carbon dioxide, and releasing energy from foods.

Digestion

Breakdown of food substances into simpler forms that can be absorbed and used.

Absorption

Passage of substances through membranes and into body fluids.

Circulation

Movement of substances in body fluids.

Assimilation

Changing of absorbed substances into different chemical forms.

Excretion

Removal of wastes produced by metabolic reactions.

Metabolism

The collection of chemical reactions in cells that support life.

Major Requirements of Organisms

Water, Food, Oxygen, Heat, Pressure.

Homeostasis

The body's ability to keep its internal conditions stable so that cells can survive, despite changes in outside environment.

Effector

An organ or cell that acts in response to a stimulus to restore balance.

Body cavities

Spaces within the body that separate compartments, allowing for communication and containment of infection.

Cranial cavity

The space within the skull that houses the brain.

Vertebral canal

The canal formed by the vertebrae that contains the spinal cord.

Thoracic cavity

The chamber of the body that is protected by the rib cage and contains the lungs and heart.

Abdominopelvic cavity

The cavity that encompasses both the abdominal and pelvic regions.

Serous membranes

Double-layered structures that line organs and secrete serous fluid to reduce friction.

Integumentary system

Protects tissues, regulates body temperature, and supports sensory receptors.

Skeletal system

Provides framework, protects soft tissues, provides attachment for muscles, produces blood cells, and stores inorganic salts.

Muscular system

Causes movements, maintains posture, and produces body heat.

Nervous system

Detects changes, receives and interprets sensory information, and stimulates muscles and glands.

Endocrine system

Controls metabolic activities of body structures.

Cardiovascular system

Moves blood through blood vessels and transports substances throughout the body.

Lymphatic system

Returns tissue fluid to the blood, carries certain absorbed food molecules, and defends the body against infection.

Digestive system

Receives, breaks down, and absorbs food while eliminating unabsorbed material.

Respiratory system

Responsible for the intake and output of air and the exchange of gases between air and blood.

Urinary system

Removes wastes from blood, maintains water and electrolyte balance, and stores and eliminates urine.

Male reproductive system

Produces and maintains sperm cells and transfers sperm cells into the female reproductive tract.

Female reproductive system

Produces and maintains egg cells, receives sperm cells, supports embryo development, and functions in the birth process.

Anatomical position

Standing upright with face and toes forward, arms at sides with palms facing forward, and feet parallel.

Body Planes

Imaginary lines that divide the body into sections, including sagittal, transverse, and frontal.

Axial skeleton

The part of the skeleton that includes the skull, vertebral column, and rib cage.

Appendicular skeleton

The part of the skeleton that includes the limbs and pelvic girdle.

Right upper quadrant

Left upper quadrant

Left lower quadrant

Right lower quadrant

Right hypochondriac region

Left hypochondriac region

Epigastric region

Right lumbar region

left lumbar region

umbilical region

Right iliac region

Hypogastric region

Left iliac region