Comprehensive Human Body Systems: Anatomy, Physiology, and Pathophysiology

Coronal plane

An imaginary line that divides the body into front and back sections.

Frontal plane

Another name for the coronal plane; divides the body into anterior and posterior sections.

Sagittal plane

An imaginary line that divides the body into left and right sections.

Lateral plane

Another name sometimes used for the sagittal plane.

Midsagittal plane

Divides the body into equal left and right halves.

Midline plane

Another name for the midsagittal plane.

Transverse plane

Divides the body horizontally into top and bottom sections.

Axial plane

Another name for the transverse plane.

Body planes

Imaginary straight lines used to divide the body into sections.

Cells

The basic foundation of the human body.

Tissue

Groups of cells that share a common function.

Organs

Groups of tissues that perform similar or related jobs.

Body systems

Groups of organs that work together to perform similar functions.

Skeletal system

The body system made of bones that supports, protects, and allows movement.

Main functions of the skeletal system

Provides structure, protects organs, allows movement, stores calcium, and helps make blood cells.

Number of bones in the adult skeleton

206 bones.

Axial skeleton

The part of the skeleton that forms the body's central axis from skull to coccyx.

Axial skeleton includes

Skull, facial bones, thoracic cage, and vertebral column.

Appendicular skeleton

The part of the skeleton made of the arms, legs, and where they attach to the axial skeleton.

Pelvis classification

The pelvis includes parts of both the axial and appendicular skeleton.

Joint

The place where two bones meet.

Ligaments

Fibrous tissues that connect bone to bone and stabilize joints.

Cartilage

Semirigid flexible tissue that cushions the ends of bones.

Tendons

Tissues that attach muscle to bone.

Symphyses

Joints where only slight movement is possible.

Joint capsule

A fibrous sac that holds the bone ends of a joint together.

Articular cartilage

Cartilage that allows bone ends to glide smoothly.

Synovial membrane

The inner lining of the joint capsule.

Synovial fluid

Fluid produced by the synovial membrane that allows bones to glide over each other.

Ball-and-socket joint

A joint that allows rotation and bending.

Example of a ball-and-socket joint

The shoulder joint.

Hinge joint

A joint that allows bending and straightening only.

Flexion

Bending a joint.

Extension

Straightening a joint.

Bronchi

Airways that enter the lungs and branch into smaller airways.

Bronchioles

Smaller airway branches inside the lungs.

Alveoli

Tiny air sacs where oxygen and carbon dioxide exchange occurs.

Lung lobes

Sections of each lung.

Pleura

Membranes that help the lungs move smoothly.

Visceral pleura

Pleura that covers the lungs.

Parietal pleura

Pleura that lines the chest wall.

Pleural fluid

Thin fluid between pleura that helps lung movement.

Pleural space

Potential space between visceral and parietal pleura.

Diaphragm

The primary muscle of breathing.

Inhalation

Breathing in.

Inhalation muscle action

Diaphragm and intercostal muscles contract.

Inhalation pressure change

Thoracic pressure decreases, pulling air into the lungs.

Negative-pressure ventilation

Normal breathing where air is pulled into the lungs.

Exhalation

Breathing out.

Exhalation muscle action

Diaphragm and intercostal muscles relax.

Respiratory system function

Provides oxygen and eliminates carbon dioxide.

Ventilation

Movement of air between the lungs and the environment.

Diffusion

Passive movement of molecules from high concentration to low concentration.

Chemical control of breathing

The brainstem controls breathing by monitoring carbon dioxide levels.

Medulla oblongata

Part of the brainstem that stimulates breathing.

Phrenic nerve

Nerve that signals the diaphragm to contract.

Hypoxic drive

Backup breathing control system based on low oxygen levels.

Pons

Brainstem area that helps adjust depth of breathing during stress.

Tidal volume

Amount of air moved in or out of the lungs in one breath.

Normal adult tidal volume

About 500 mL.

Stroke volume

Amount of blood moved by one heartbeat.

Cardiac output

Amount of blood moved in one minute.

SA node

Sinoatrial node where electrical impulses normally begin.

Arteries

Carry blood away from the heart.

Capillaries

Tiny vessels where blood contacts body tissues.

Veins

Return oxygen-depleted blood to the heart.

Blood pressure

Force of blood against artery walls.

Systole

Phase when the left ventricle contracts and pumps blood into the aorta.

Diastole

Phase when the ventricle relaxes and fills with blood.

Perfusion

Circulation of blood through organs and tissues in amounts needed by cells.

Shock

A state of inadequate tissue perfusion.

Coagulation

Blood clotting.

Nervous system

The complex body system that controls body activity and responses.

Central nervous system

Brain and spinal cord.

Peripheral nervous system

Nerves outside the brain and spinal cord.

Somatic nervous system

Controls voluntary activities.

Autonomic nervous system

Controls automatic body functions.

Cerebrum

Largest part of the brain responsible for higher brain function.

Brain hemispheres

Two halves of the cerebrum.

Frontal lobe

Controls personality, judgment, planning, problem solving, concentration, and self-awareness.

Parietal lobe

Controls spatial recognition.

Occipital lobe

Controls vision.

Temporal lobe

Controls taste, hearing, and understanding words.

Cerebellum

Controls balance, coordination, and posture.

Brainstem

Controls life functions including breathing, heart function, and consciousness.

Brainstem parts

Midbrain, pons, and medulla oblongata.

Reticular activating system

Regulates consciousness.

Cerebrospinal fluid

Fluid that filters impurities and absorbs shock.

Head oxygenated blood supply

Carotid arteries.

Head venous drainage

Internal and external jugular veins.

Spinal cord

Extension of the brainstem through the vertebral column.

Spinal cord exit from skull

Through the foramen magnum.

Spinal cord ending level

Ends around the second lumbar vertebra.

Spinal cord function

Transmits messages between the brain and body.

Sensory nerves

Carry sensory information to the brain.

Motor nerves

Carry signals from the brain to muscles.

Skin

The largest single organ in the body.

Integumentary system

The skin system.

Epidermis

Superficial layer of skin.

Epidermis function

Forms a protective watertight barrier.