anatomy & physiology ch 1 (b)

ch 1 (b)

Standard anatomical position

body erect, feet slightly apart, palms facing forward w. thumbs pointing away from body

what is the purpose of directional terms

-they describe one body structure in relation to another body structure

-direction is always based on standard anatomical position

-right and left refer to the body being viewed, not right and left of observer

Superior (cranial)

-toward the head end or upper part of a structure or the body; above

-the head is superior to the abdomen

inferior (caudal)

-away from the head end or toward the lower part of a structure or the body; below

-the naval is inferior to the chin

anterior (ventral)

-toward or at the front of the body; in front of

-the breastbone is anterior to the spine

posterior (dorsal)

-toward or at the back of the body; behind

-the heart is posterior to the breastbone

medial

-toward or at the mideline of the body; on the inner side of the

-the heart is medial to the arm

lateral

-away from the midline of the body; on the outer side of

-the arms are lateral to the chest

intermediate

-between a more medial and a more lateral structure

-the collarbone is intermediate between the breastbone and shoulder

proximal

-closer to the origin of the body part or the point of attachment of a limb to the body trunk

-the elbow is proximal to the wrist

distal

-farther from the origin of a body part or the point of attachment of a limb to the body trunk

-the knee is distal to the thigh

superficial (external)

-toward or at the body surface

-the skin is superficial to the skeletal muscles

deep (internal)

-away from the body surface; more internal

-the lungs are deep to the skin

Axial

head, neck, and trunk

appendicular

limbs (legs & arms)

three most common planes that may be cut for anatomical study

sagittal plane, frontal (coronal) plane, transverse (horizontal) plane

what are cuts made along a body plane called?

they are named after plane, so a sagittal cut results in a sagittal section

sagittal plane

-divides body vertically into right and left parts

-produces a sagittal section if cut along this plane

midsagittal (median) plane

cut was made perfectly on midline

parasagittal plane

cut was off-centered, not on midline

front (coronal) plane

-divides body vertically into anterior and posterior parrots (front and back)

-produces a frontal or coronal section

transverse (horizontal) plane

-divides body horizontally (90 degress to vertical plane) into superior and inferior parts (top and bottom)

-produces a cross section

oblique section

-result of cuts at angle other than 90 degress to vertical plane

What do internal cavities provide?

different degrees of protection to organs within them

two sets of cavities

dorsal body cavity, ventral body cavity

what does the dorsal body cavity do

it protects the fragile nervous system

purpose of cranial cavity and vertebral cavity

encases brain (cc), encases spinal cord (vc)

viscera

houses the internal organs

two subdivisions separated by the diaphragm

thoracic cavity and abdominopelvic cavity

Abdominopelvic cavity

-abdominal cavity, contains stomach, intestines, spleen, and liver

-pelvic cavity, contains urinary bladder, reproductive organs, and rectum

thoracic cavity

two pleural cavities, each cavity surrounds one lung

mediastinum

contains pericardial cavity, surrounds other thoracic organs, such as esophagus, trachea, etc

pericardial cavity

encloses heart

Homeostatic imbalance

problems occur when structures stray into neighboring cavities

ex. hiatal hernia (part of stomach protrudes through diaphragm into thoracic cavity), can push stomach acid into esophagus causing irritation (heartburn)

-severe cases may require surgical repair

serous membranes

membranes in ventral body cavity

-serosa (also called serous membrane): thin, double-layered membranes that cover surface in ventral body cavity

parietal serosa

lines internal body cavity walls

visceral serosa

covers internal organs (viscera)

what are double layers separated by?

slit-like cavity filled with/ serous fluid (fluid secreted by both layers of membrane)

pericardium cavity

heart

pleurae cavity

lungs

peritoneum cavity

abdominopelvic cavity

what does a fist thrust into a flaccid balloon demonstrate

the relationship between the parietal and visceral serous membrane layers

homeostatic imbalance

-serous membranes can become inflamed as a result of infection or other causes

-normally smooth layers can become rough and even can stick otgether, resulting in excruitating pain

-ex. pleurisy and peritonitis

abdominopelvic quadrants

quadrants and divisons used primarily by medical personnel

quarters:

right upper quadrant (RUQ)

left upper quadrant (LUQ)

right lower quadrant (RLQ)

left lower quadrant (LLQ)

abdominopelvic regions

-right hypochondriac region

-epigastric region

-left hypochondriac region

-right lumbar region

-umbilical region

-left lumbar region

-right iliac (inguinal) region

-hypogastic region

-left iliac (inguinal) region

smaller body cavities exposed to environment

oral & digestive cavities, nasal cavity, orbital cavities, middle ear cavities

-NOT exposed to environment, synovial cavities: joint cavities