intro to anatomy: planes of reference; directional terms; levels of organization

Anatomical position

Upright with feet flat on floor, arms along the sides of the body with the palms facing forward. Face and feet facing directly forward.

Superior

Above

Ex: head is superior to the neck; eyes are superior to the nose

Inferior

• Below

• Ex: neck is inferior to the head; mouth is inferior to my scalp.

Anterior (ventral)

• Towards the front

• Ex: nose is anterior to the ears

Posterior (dorsal)

• towards the back

• Ex: ears are posterior to the eyes

Medial

• Towards the center/midline

  ex: the sternum is medial to the clavicle (collarbones)

Lateral

• Towards the outside of the body

  ex: the eyes are lateral to the nose

Deep (internal)

• Deeper in the body

  ex: the brain is deep to the skull

Superficial (external)

• towards the outside/surface of the body

  ex: my scalp is superficial to my brain

proximal

• closer to the point of origin (where it starts)

• Ex: the elbow is proximal to the wrist

• * proximal is used for appendages, as well as blood vessels and nerves

Coronal (frontal) plane

• separates the anterior and posterior sides

• Not symmetrical

sagittal plane

• separates the body of the organs in left and right

Distal

• Farther from the point of origin

• Ex: my fingertips are distal to my elbow

• * distal is used for appendages, as well as blood vessels and nerves

midsagittal

• separates the body in perfect halves, left and right

• Symmetrical

Parasagittal

• Not directly in the middle

• Not symmetrical

• Ex: parasagittal section of the shoulder

Transverse (cross – sectional) plane

• Sections the body from the superior and inferior sides

• Not symmetrical

Oblique section

• A diagonal cut; cuts the structure at an angle; will give us an oval shape

Longitudinal section

• A horizontal section where you’re cutting in a parallel direction with each leg structure, where you can see the lumen in its entirety

  * lumen- the space between and organ

Atoms

Small units that belong to an element

Molecules

atoms that come together; ex: two hydrogen atoms and two oxygen atoms make a water molecule

Proteins

• Proteins are essential, complex molecules made of amino acid chains, acting as building blocks for muscles, organs, and tissues

• We have more than 50,000 proteins

• If one of these proteins doesn’t work that person might have a disorder

Carbohydrates

The basic and main source of fuel

Lipids

Fats; essential for storing energy; helps cushion organs; produces testosterone and estrogen

Cells

• Putting all three of these molecules together (proteins, carbohydrates, lipids).

• We have thousands of different types of cells

Tissues

• A structure made up of many cells that perform a particular function

• Ex: epithelial tissues create barriers; connective tissue connects things to another thing

Organs

• Made up of four different types of tissues

• An organ must have at least two of the four major tissues

Organ system

• A bunch of organs together

• Ex: digestive system; the nervous system; cardiovascular system, etc.

Organism

• Put all those organ systems together we get an organism

• Ex: a human body