AN ORIENTATION TO THE HUMAN BODY

Human Biology It is the structural, functional, behavioral basis of the human organisms’ ability to adapt to and survive in its environment.

NECESSARY LIFE FUNCTIONS Maintain boundaries – Movement Process of metabolism Maintain homeostasis Reproduction Responsiveness/irritability Growth

TRUE FOR: Unicellular Made up of one cell Example – ameba, Maintain boundaries – cell membrane Multicellular Made up of many cells Example – humans Maintain boundaries – skin Must maintain homeostasis for single cell as well as for organism

Survival Needs Nutrients Oxygen water body temperature Appropriate atmospheric pressure

ORGANIZATION OF HUMAN BODY Cell Tissues Organ Organ system Organism Population Community Ecosystem/biome biosphere

FEEDBACK SYSTEM Feedback system is a cycle of events in which the status of a body condition is continually monitored, evaluated, changed, remonitored, reevaluated continuously.

HOMEOSTATIC CONTROL MECHANISMS Receptor Control center Effector

MAINTAINING HOMEOSTASIS Negative feedback system Positive feedback system

HOMEOSTATIC IMBALANCE Most diseases are a result of disturbances in the body’s homeostasis Efficiency decreases with age

LANGUAGE OF ANATOMY Provides ways to accurately describe the body

ANATOMY Study of structure and shape of the body and body parts and their relationship to each other Gross anatomy – study of large observable structures Microscopic anatomy – study of structures that require a microscope to been seen

PHYSIOLOGY Study of how the body and its parts function.

Structure determines function. Governing rule in anatomy

Terms Disorder Disease Symptom Signs Pathology Epidemiology Pharmacology diagnosis Infectious disease Pathogens Local disease Systemic disease

ANATOMICAL POSITION Standard position Basis for directional terms

DIRECTIONAL TERMS Explain exact location of 1 body structure in relation to another.

REGIONAL TERMS Anterior body landmarks – toward / at front of body Posterior body landmarks – toward / at back of body

BODY PLANES AND SECTIONS Imaginary line through the body wall or organ

Three sections Sagittal section Frontal (coronal) plane Transverse sections (cross-section)

BODY CAVITIES TWO MAIN CAVITIES 1.Dorsal Cavity 2.Ventral Cavity

Dorsal cavity 2 divisions that are continuous with each other 1.Cranial – space for brain 2.Spinal cavity – space for spinal cord Foramen magnum – opening at base of brain allows for spinal cord to connect with brain

Ventral cavity 1. Thoracic cavity – separated from rest of ventral cavity by diaphragm surrounded by ribs houses heart, lungs 2. Abdominopelvic a. abdominal – superior cavity houses stomach, liver, intestines b. Pelvic – inferior cavity houses reproductive organs, bladder, rectum

9 regions of abdominopelvic Right hypochondriac region Left hypochondriac region Right lumbar region Left lumbar region Right iliac region Left iliac region Epigastric region Umbilical region Hypogastric region

CRANIAL CAVITIES Sphenodial sinus Frontal sinus Orbital cavity Nasal cavity Oral cavity Middle ear cavity Cranial cavity

Medical imaging Bombards the body with energy to reveal structures of internal organs, and chemical processes of body

X-RAY Oldest Visualize hard bony structures Locate abnormally dense structures such as tumors and TB nodules

ULTRASOUND Sonography Equipment is inexpensive Uses high frequency sound waves So far, no harmful effects on living tissue Determines fetal age, position: locating placenta.

CT SCAN Computer tomography Confines its beam to a thin slice of tissue Like a refined version of X-ray Eliminated exploratory surgery Patient is moved through a doughnut shaped CT machine – tube rotates around bed

PET Positron-emission tomography it sends images about metabolic processes Insights into brain activity (mental illness, Alzheimer’s disease, epilepsy) Uses radioisotopes

MRI Magnetic resonance imaging Uses magnetic fields 3,000 to 60,000 times stronger than the earth’s Bones do not show up thus they do not interfere with viewing soft tissue behind bone Good at picking up degenerative diseases – ex MS Very expensive