Introduction to A&P

Anatomy – study of the structure of an organism and the relationships of its parts - Greek for “cutting up” -What it is- Physiology – study of the functions of living organisms and their parts. -What it does-

Levels of Organization Cells – smallest unit of “living” matter in the body Tissues – group of cells working together to perform a function Organs – tissues of various types working to perform a special function Systems – organs working together to perform a complex function Organism – everything (cells, tissues, organs, systems) working together to allow life to exist

Anatomical Position Reference position Standing posture, arms to the side, palms turned forward, head and feet facing forward

Anatomical Directions Anatomical directions allow you to explain a location more accurately. Instead of saying “The cut is at the bottom of the thigh” which doesn’t say exactly where the cut is, you would say “The cut is on the posterior side of the distal end of the femur”

Anatomical Directions (Cont.) Superior – “towards the head” Inferior – “towards the feet” Anterior – “front” also known as “ventral” Posterior – “back” also known as “dorsal” Medial – “toward the midline of the body” Lateral – “away from the midline of the body”

Anatomical Directions (Cont.) Proximal – “toward or nearest the trunk of the body” Distal – “away or farthest from the trunk of the body” Superficial – “nearer the surface” Deep – “ farther away from the body surface”

Planes of the Body Sagittal – length-wise from front to back Frontal (Coronal) – divides body into front and back portions Transverse – Divides the body into upper and lower portions

Body Cavities Cranial (brain) Spinal (spinal cord) Thoracic - mediastinum (heart) - pleural (lungs) Abdominopelvic - Abdominal (liver) - Pelvic ( Bladder)

Autopsies Greek (Auto = self, opsis = view) Procedure that helps to determine the cause of death Helps to further future medical research

Homeostasis Keeps the internal environment consistent Feedback loop – how the body controls its environment Sensor – senses change in environment and relays change to “Control Center” Control center – receives information and activates the “Effector” Effector – changes environment back to acceptable level

Thermostat Sensor = thermometer Control center = thermostat Effector = furnace When temperature reaches normal levels the sensor no longer sends information to the control center

Negative Feedback Loop Most feedback loops in the body are negative They oppose change in the body and try to bring the body back to a normal state

Positive Feedback Loop Positive feedback loops cause change in the body Returning to “normal” is not the goal of PFL’s Childbirth = uterine contractions