Anatomy and Physiology - Respiratory System

Respiratory System

Main functions

1. to conduct air into the lungs
2. to deliver oxygen via capillary membranes to the blood
3. to remove carbon dioxide
4. regulation of acid-base

Respiration can be divided into 3 parts:

1. Ventilation – movement of air from outside to inside the body and its distribution within the trachea-bronchial system to gas exchange units in the lungs
2. Perfusion – flow of blood through the lungs
3. Diffusion – transfer of gases across the alveolar-capillary membrane to the blood in the pulmonary capillaries

The nervous system controls the movement of the respiratory muscles and adjusts the rate of breathing so that it matches the need of the body during various activities. Poor air quality is the major cause of respiratory disease.

Anatomy and Physiology - Cardiovascular System

HEART

The heart is the root of life and causes the versatility of the spiritual faculties. The heart influences the face and fills the pulse with blood. (Huang Ti. The Yellow Emperor)

Heart – is a four chambered muscular pump approximately the size of a man’s fist that beats an average of 70 beats per minute.

Cardiac Cycle – rhythmic pumping of the heart

Systole – the period during which the ventricles are contracting

Diastole – the period during which the ventricles are relaxed and filling with blood

Cardiac output – the volume of blood ejected per minute by rhythmic ventricular contraction approximately between 4 to 8 liters per minute

              CO=[EDV-ESV] x HR

EDV – end diastolic volume

ESV – end systolic volume

HR – Heart rate

Preload – represents the volume work of the heart. It is the work imposed on the heart before contraction. It also represents the amount of blood that the heart must pump with each beat and is largely determined by the venous return to the heart and the accompanying stretch of the muscles

Afterload – is the pressure or tension work of the heart. It is the pressure that the heart must generate to move blood into aorta. It is called afterload because it is the work presented to the heart after the contraction has commenced