OBJECTIVEWithout reference, identify at least four out

of six principles about anatomy and physiology as they relate to general

medical equipment.

Anatomy and Physiology

Circulatory System Functions Respiration

Oxygenated blood is delivered from the lungs to the body

Carbon dioxide enriched blood is carried from the body to the lungs

Nutrition - erythrocytes carry food absorbed from the intestines to the tissue cells

Anatomy and Physiology (Continued)

• Protection Leukocytes fight infection Thrombocytes aid in the clotting

process to stop bleeding • Excretion - waste products are removed

from the cells and carried to kidneys for filtration and removal

Anatomy and Physiology (Continued)

• Regulation Temperature - the circulation of blood in the body acts similar to the circulation of anti-freeze in a combustion engine

Hormone distribution

Anatomy and Physiology (Continued)

Two main divisions • Pulmonary - refers to the respiratory functions of the circulatory system (oxygenation and de-oxygenation of blood) • Systemic - refers to the distribution of nutrients throughout the body

Anatomy and Physiology (Continued)

Heart – a four chambered muscular pump about the size of a fist that lies tilted to the right in the chest with the apex (pointed end) resting on the top diaphragm and the base (broad end) on the top

Anatomy and Physiology (Continued)

The pericardium is a sac like structure surrounding the heart that contains a fluid which cushions and lubricates the heart

The right atrium is the chamber that collects de-oxygenated blood from the body

Anatomy and Physiology (Continued)

The right ventricle is the pumping chamber that sends de-oxygenated blood to the lungs for oxygenation

The left atrium is the chamber use for collecting oxygenated blood from the lungs

The left ventricle is the pumping chamber that sends oxygenated blood to the body

Anatomy and Physiology (Continued)

Layers of the HeartThe outer layer is the epicardiumThe middle layer which is comprised of

muscle tissue is the myocardiumThe inner layer lining the camber walls

is the endocardium.

Anatomy and Physiology (Continued)

The sinoatrial node is the impulse generating (pacemaker) tissue located in the right atrium

The atrioventricular node conducts the normal electrical impulse from the atria to the ventricles, located between the atria and ventricles

Anatomy and Physiology (Continued)

The bundle of hiss is the small band of specialized cardiac muscle fibers that maintain the normal sequence of the heartbeat by conducting energy from the right atrium to the ventricles

Purkinje fibers – conducts the pacemaker stimulus along the inside walls of the ventricles to all parts of the heart

Anatomy and Physiology (Continued)

Myocardial cell activity Polarization

Heart cells are charged (polarized) negatively in the resting state»Negatively charged interior»Positively charged surface

No physical response, only electrical activity

Anatomy and Physiology (Continued)

DepolarizationWhen electrically stimulated, the heart

cells become positively charged (depolarized)

The physical response of the cells to depolarization is contraction of the heart

RepolarizationFollowing contraction, the electrical

realigning of the heart cells to their polarized state

Returns to resting state

Anatomy and Physiology (Continued)

Electrical activity of the heart cells Produces approximately -90 mv of

electricity in the resting state (polarized) +20 to +40 mv of electricity when fully

depolarized Passes through the heart and is picked

up by external skin electrodes and recorded as an electrocardiogram

Anatomy and Physiology (Continued)

Blood vessels • Arteries - thick walled, elastic vessels which carry blood away FROM the heart Arterioles - small branches of arteries

which control blood flow by constriction and dilation

Anatomy and Physiology (Continued)

• Capillaries - smallest blood vessels with walls only one cell thick. All exchanges of food and oxygen occur here • Veins - large, thin walled, non-muscular vessels which carry blood back to the heart. Veins also contain valve to prevent back flow Venules - small beginning branches of

veins

Anatomy and Physiology (Continued)

Blood • Cellular portion makes up about 45% of the

blood volume Red blood cells (RBC) - carry oxygen White blood cells (WBC) - fight infection Platelets - aid in coagulation

Anatomy and Physiology (Continued)

• Liquid (plasma) portion makes up about 55% of the blood volume Acts as a support for the cellular portion of the blood

Contains dissolved nutrients and chemicals

Anatomy and Physiology (Continued)

Major arteries Pulmonary - connects the right ventricle

with the lungs Aorta - carries blood from the left

ventricle to the body

Anatomy and Physiology (Continued)

Coronary (right and left) - first branch from the aorta, supplies the heart muscle with blood

Femoral - supplies the legs Brachial - supplies the arms Carotid - supplies the head

Anatomy and Physiology (Continued)

Anatomy and Physiology (Continued)

Coronary Artery

Major veins Superior vena cava - returns blood from

the head, arms and upper chest Inferior vena cava - returns blood from

the legs, abdomen and lower chest Most veins have the same name as their

corresponding artery

Anatomy and Physiology (Continued)

Anatomy and Physiology (Continued)

Vein Viewer – uses infrared and projector to view veins in real time

Respiratory system Terms External respiration is the exchange of

gases between an organism and its environment

Diffusion is the gaseous exchange of air in the alveoli of the lungs with the blood

Internal respiration is the exchange of air in the capillaries with body cells

Anatomy and Physiology (Continued)

Structures of the respiratory system• Nasal cavity

Warms and moistens the air entering the body

Lined with cilia to remove dust and foreign particles (aided by mucous)

• The Pharynx is the pathway for breathing as well as a muscular tube for the passage of food• The larynx is known as the organ of sound

(voice box)

Anatomy and Physiology (Continued)

Trachea (windpipe) A rigid tube constructed of

cartilaginous ringsLined with cilia to acts as a filterRuns anterior to the esophagus from

the larynx to where it branches

Anatomy and Physiology (Continued)

Bronchial treeBronchi – a branching set of tubes from

the trachea which leads to the lungsBronchioles – smaller branches of

bronchi which conduct air into the lungs

Anatomy and Physiology (Continued)

AlveoliSmall sac like structures at the end of the

bronchiolesAlveoli sacs are surrounded by capillariesSeparation between the sacs and

capillaries is very thinOxygen and carbon dioxide readily diffuse

between air and the blood in the capillaries

This is the only place gas exchange takes place in the body

Anatomy and Physiology (Continued)

LungsThe primary organ for respirationConsists of two cone shaped organs

Anatomy and Physiology (Continued)

Divided into lobes – the right lung has three lobes and the left lung has two lobes

The pleura is the membrane which surrounds the lungs»Each lung has its own pleura»Filled with pleura fluid to reduce

friction

Anatomy and Physiology (Continued)

Muscles of respirationThe diaphragm is a dome shaped

muscle which forms the floor of the thoracic cavity»The main muscle of respiration»Contraction causes inspiration by

moving down and enlarging the cavity

Anatomy and Physiology (Continued)

Anatomy and Physiology (Continued)

Intercostal muscles are located between the ribs; contraction causes inspiration

Phases of respirationInspiration»Fresh air is taken into the lungs»Oxygen diffuses in the blood and

carbon dioxide diffuses into the airExpiration – air is expelled

Anatomy and Physiology (Continued)