Anatomy
study of the body's structures & the relationships between structure and function.
Physiology
the study of body's functions (processes - can also be studied on many levels)
Basic life processes
Metabolism, responsiveness, movement, growth, differentiation, and reproduction
Homeostasis
the maintenance of a relatively constant internal environment. Maintains variables (Ex. body temperature, blood pressure, etc.) near a "set point", within a narrow range.
Control of homeostasis
done by all systems, but primarily by endocrine & nervous systems, working separately or together. Usually accomplished by negative feedback systems.
Negative feedback systems
maintain homeostasis; a deviation from a set point is resisted. Regulates conditions in the body that remain stable for long periods of time (Ex. blood pressure).
Positive feedback systems
not homeostatic, deviation from the set point gets ever greater until interrupted by some outside force (childbirth, lactation, orgasm)
All feedback systems have 3 components
Receptor, control center, effector
Receptor
detects changes in variable, sends info to the control center
Control center in spinal cord and brain
assesses the info & coordinates a response. Sends output to the effector.
Effector
muscle or gland that carries out the response (effect)
Anatomic position
person standing erect facing forward, feet forward and flat on the floor, arms at the sides with the palms facing forward,
Supine
body reclining face up
Prone
body reclining face down
Longitudinal
through long axis
Transverse
at right angles to the long axis
Oblique
cut across the long axis at an angle other than a right angle
Anatomical terminology
Anatomical position, Supine, prone
Body regions
limbs: upper, lower, central region: head, neck, trunk (thorax, abdomen, pelvis)
Major planes of the body
Sagittal, transverse (midsagittal, parasagittal), frontal (coronal)
Sections of organs
Longitudinal, Transverse, Oblique
Body cavities
Dorsal, Ventral
Dorsal
cranial (holds brain) & vertebral (holds spinal cord)
Ventral
Thoracic (above diaphragm; contains pericardial cavity & 2 pleural cavities) & Abdominopelvic (below diaphragm). The mediastinum is the central area of the thorax, containing all thoracic organs except the lungs.
Membranes
sheets of cells that line body cavities
Mucous Membrane
line body cavities that open to the outside of the body ( ex. digestive tract , reproductive tract)
Serous Membrane
line body cavities that do not open to the outside -line the walls of thoracic & abdominopelvic cavities, & cover the viscera within these cavities.
Serous membranes consist of 2 layers
The Parietal Layer, The Visceral Layer
The Parietal Layer
lines the walls of the cavity
The Visceral Layer
covers & adheres to the viscera
Serous Fluid
lubrication, fills the cavity between the two membranes
Three types of serous membranes
pleura (two, each surrounds a lung), pericardium (surrounds the heart), and the peritoneum
Pleura
1. Serous membrane of the pleural cavities
Visceral Pleura
adheres to the surface of the lungs
Parietal Pericardium
lines the chest wall
Peritoneum
3. Serous membrane of the abdominal cavity
Visceral Peritoneum
covers the abdominal viscera
Parietal Peritoneum
lines the abdominal wall
retroperitoneal organs (kidneys, adrenal glands, pancreas, part of the intestines, bladder)
Some organs lie outside the peritoneal cavity, between the parietal peritoneum and the body wall
Abdomen
can be divided into quadrants, or even further divided into 9 regions
Medical Imaging
noninvasive way to study internal structures and diagnose many disorders.