Blood Pressure Blood pressure is the presssure that blood exerts against the walls of blood vessels. It is the main force that transports blood from the heart to the body parts. ***The pressure is highest in the arteries as they are nearest the heart. The force is greater when more blood flows through the vessel and when it is narrower.

Blood Pressure Two measurements are taken for blood pressure: Systolic pressureDiastolic pressure - it is the maximum pressure - it is the minimum pressure during contraction of left during the relaxation of the left ventricleventricle Average: 120 mmHg (men)Average: 80 mmHg (men) 110 mmHg (women) 70 mmHg (women)

High Blood Pressure -Physical exercise * bp high to transport materials more -Anxiety – stress rapidly to more active cells -Hypertension * atherosclerosis cholesterol & fats accumulate (medical problem of in the walls of arteries narrower arteries high blood pressure ) * salty food may increase blood volume *nicotine, caffeine constricts arteries

Low Blood Pressure *weakened heart can’t pump enough blood (defect in muscles or valves) Hypotension *blocked coronary artery, heart infection, aging *malnutrition –low protein diet (water lost from capillaries)

The Vessels of a Capillary Bed

Starling Hypothesis

Pathways of Human Circulation Pulmonary Circulation Systemic Circulation Coronary Hepatic Portal Renal Circulation Circulation Circulation

carries blood between lungs and heart adds oxygen and removes CO 2 from the blood begins in right ventricle and finishes in left atrium Pulmonary Circulation

Right ventricle Left pulmonary arteries Pulmonary arteries Right pulmonary arteries Left lung Right lung Left atrium Pulmonary veins Left pulmonary capillaries Right pulmonary capillaries Left pulmonary veins Right pulmonary veins

Aorta Right Pulmonary Artery Left Pulmonary Artery Right Pulmonary Vein Left Pulmonary Vein Superior Vena Cava Inferior Vena Cava

CO 2 O2O2 Gas Exchange CO 2 O2O2 Gas Exchange

Systemic Circulation - carries blood between heart and the rest of the body - begins from the left ventricle, ends in the right atrium

Systemic Circulation Left ventricle Arteries Aorta Arterioles Right atrium Vena cava Body capillaries VenulesVeins

CO 2 O2O2 O2O2

O2O2 Gas Exchange CO 2 O2O2 Gas Exchange CO 2 O2O2 O2O2

Pulmonary circulation adds _____________ and removes _____________ from the blood. Blood returning to the heart from the body tissues is low in oxygen and high in carbon dioxide. This blood enters the _____________ and flows into the _____________. This chamber of the heart pumps it through the _____________ arteries to the lungs. These are the only _____________ that carry _____________ blood. All other _____________ carry _____________ blood. As the blood travels through the capillaries in the lungs, it gains _____________ and gets rid of _____________. The pulmonary capillaries merge into pulmonary veins. These veins carry the _____________ blood to the _____________ of the heart. The _______________ are the only _____________ that carry oxygen-rich blood. All other _____________ carry oxygen-poor blood. oxygen carbon dioxide right atrium right ventricle pulmonary arteries oxygen-poor arteriesoxygen-rich oxygen carbon dioxide oxygen-rich left atriumpulmonary veins veins

From the _____________ the blood enters the _____________. Systemic circulation begins in the _____________ of the heart. From here the blood is pumped into the _____________. It branches forming arteries that serve all parts of the body. The arteries divide into arterioles an finally into _____________. These tiny blood vessels are the sites for _____________ and _____________ exchange between the blood and body cells. Capillaries merge to form veins. These veins finally return the blood to the heart. The largest veins of the body are: the _________________ which returns blood from the upper parts of the body, and ________________ which returns blood from the lower parts of the body. left atrium left ventricle aorta capillaries oxygencarbon dioxide superior vena cava inferior vena cava

Coronary Circulation Right coronary artery Aorta Right atrium Left coronary artery Coronary capillaries Right coronary veins Left coronary veins Coronary circulation supplies blood to the muscle of the heart.

Hepatic Portal Circulation  Hepatic portal circulation helps to maintain balance of glucose in the blood.  As blood passes through the liver excess glucose molecules are absorbed by liver cells; and converted into glycogen.  If the amount of glucose is less in blood then liver converts glycogen into glucose that diffuse into blood.

Hepatic Portal Circulation Capillaries in small intestine Portal vein Venules Hepatic sinuses Hepatic veinsInferior vena cava Right atrium *Hepatic portal circulation is the only circulation that capillaries (hepatic sinuses) are found between veins.

Renal Circulation It is the branch of the systemic circulation that carries blood to and from kidneys. blood transports nitrogenous wastes (urea) to the kidneys for excretion