AM

CH:1 Anatomy CLASS Notes

Organization of the body

  • Four types of tissues

  • Epithelial – Covers or lines body surfaces; epidermis, capillary walls; outer stomach lining

  • Connective – connects and supports parts of the body; bone, cartilage, blood

  • Muscle – contracts to produce movement; skeletal muscles, heart

  • Nerve – generates and transmits impulses to regulate body function; brain, nerves

Organ Systems

  • Integumentary - skin, hair, and nails; protection, temp regulation, sensation

  • Skeletal - bones, cartilage, ligaments; protect body organs, support, movement, blood formation

  • Muscular - skeletal muscles; movement, posture, heat production.

  • Lymphatic - lymph nodes, thymus, spleen, tonsils; fluid balance, making immune cells, disease defense.

  • Respiratory – nose, larynx, trachea; absorbing oxygen, releasing carbon dioxide, speech

  • Urinary – kidney, urinary bladder; waste excretion, blood volume regulation

  • Nervous – brain, spinal cord, nerves; control, regulation, and coordination of other systems

  • Endocrine – pituitary gland, adrenals, pancreas; hormone production

  • Circulatory – heart, blood vessels; oxygen and nutrient distribution

  • Digestive – stomach, small and large intestine, liver, mouth; breakdown and absorption of nutrient, waste elimination

  • Reproductive – testes (male), ovaries (female); procreation. (OTHER: Zygote, what about that thing with the moment of conception it lights up)

  • Many experts believe that the human microbiome should be another organ system.

Anatomical Terms

  • Directional, body plane, body regions, body cavities, and abdominal regions and quadrants.

  • Directional Terms

  • “right” and “left” are from patients perspective

  • Anatomical position means standing up straight, arms at the side with palms facing forward

  • Midline – down the middle (through the nose)

  • Lateral – away from midline

  • Distal – farthest from point of origin

  • Proximal – closest to point of origin

  • superior – above

  • inferior - below

  • Anterior/Ventral - front of the body

  • Posterior/Dorsal - back of the body

- Superficial - at or near the body’s surface

- deep - away from the body’s surface

- Body Planes

- Divides the body organs into sections

- Sagittal - Divides the body lengthwise into left and right sides.

- Called midsagittal if the division is made directly on the midline

- Transverse (or horizontal) - Divides the body horizontally into superior and inferior portions.

- Used by CT scanners for organ scans

- Frontal (or coronal) - divides the body lengthwise into anterior posterior portions.


Anatomical Terms

- Body Regions

- Used while performing clinical examinations and medical procedures.

- Cephalic – Head

- Frontal – Forehead

- Nasal – Nose

- Orbital – eye

- Cervical – Neck

- Deltoid – Shoulder

- Sternal – Sternum

- Pectoral – Chest

- Brachial – arm

- Antebrachial – forearm

- Carpal – Wist

- Digital – Fingers

- Femoral – Thigh

- Patellar – knee

- Tarsal – ankle

- Pedal – Foot

- Cranial – Surrounding the brain

- Otic – ear

- Occipital – back of head

- Lumbar – lower back

- Gluteal – Buttock

- Plantar – Sole of foot


  • Body cavities are spaces in the body that house internal organs

  • Two main body cavities: ventral and dorsal

  • Ventral Cavity

- Front of the body

- Made of two cavities that are separated by the diaphragm

- Thoracic cavity

- Area surrounding the ribs and chest

- Includes the lungs and heart

- Abdominpelvic cavity

- Space containing most of the digestive tract (stomach, intestines, spleen, liver) and the urinary and reproductive organs.


  • Dorsal Cavity

  • Cavities in the back of the body

  • Divided into two cavities with one continuing into the next

  • Cranial cavity – contains the skull and brain

  • Spinal cavity – contains the vertebrae and spinal cord

8/21/25

Homeostasis

  • Homeostasis is the state of the of the body being in internal balance despite changes in external conditions

    • Because the body attempts to actively maintain balance, it is often referred to a dynamic equilibrium.

  • The body operates within a narrow range of temperature, fluids, and chemicals.

    • The “normal” range is called the set point range.

      • Body temp set point: 97-99 F (36-37 C)

  • Falling out of homeostasis results in illness or even death

  • 8/22/25

  • Results of Homeostatic Imbalance

    • Undernourished Cells

    • Toxic waste accumulation

    • Disease

      • Type 1 Diabetes — inability to release insulin to balance glucose from a person’s diet, resulting in excess glucose in blood and damage to other organs.

  • All organ systems help maintain homeostasis together

  • Homeostatic Regulation

    • The process of adjusting to the environment

    • A receptor: receives info about environmental changes

    • A control center: receives and processes info from the receptor

    • An effector: responds to signals from the control center by either opposing or enhancing the stimulus.

      • The effector sends out signals called feedback, which are either positive or negative.

      • Negative Feedback: Opposes the stimulus and reverses the direction of change.

        • Most systems operate using negative feedback

      • Positive Feedback reinforces the stimulus and amplifies the direction of change.