Blood Circulation and Transportation (Mammalian Cardiovascular System …
Blood Circulation and Transportation
Definition of circulation
The major purpose of moving a fluid in the body is to provide rapid mass transport over distance where diffusion is inadequate or too slow.
transports oxygen and nutrients to the cells.
picks up wastes, which are excreted by the lungs or kidneys.
gas exchange and nutrient-for-waste exchange occur at blood capillaries.
No cell in the body of an animal is far from a capillary.
transport heat and transmit force.
Closed Circulatory System
Single Loop (Fishes)
Heart only pumps blood to gills
A single atrium and a single ventricle
Blood is fully enriched with oxygen when it leaves gills.
Two circuit pathway
heart pumps blood to all parts of the body except for the lungs
heart pumps blood to the lungs
Amphibian and Most reptiles
Two atria, single ventricle
Deoxygenated bloods pumped out from the ventricle, entered the pulmonary circuit to the lung or skin. Oxygenated bloods are also pumped out from the ventricle, entered the systemic circuit to the rest of the body.
better circulation system compared to single loop.
oxygenated and deoxygenated bloods are kept separated.
Birds, Mammals and some Reptiles
Two atria and two ventricles
Complete separation of pulmonary and systemic circuits
Right ventricle pumps blood to the lungs.
The larger left ventricle pumps blood to the rest of the body.
Absence of circulatory system BUT presence of gastrovascular cavity
The cells are either part of an external layer, or they line in the gastrovascular cavity.
Each cell is exposed to water and can exchange gases, nutrients uptake, and get rid of wastes.
Trilobed gastrovascular cavity branches throughout small, flatenned body, nutrient diffuses from cell to cell.
Open circulatory System
Haemocyanin (copper based)
in arthropods and molluscs
Heart pumps hemolymph via vessels into tissue spaces and hemolymph drains back to the heart.
heart contraction creates negative pressure and draws the blood from the heamocoel into the heart via the ostia.
has colorless blood
Hemolymph transports nutrients
Tracheae take oxygen directly to flight muscles.
Closed Circulatory System
Haemoglobin (Iron based)
found in annelids (earthworms)
Heart pumps blood, blood moves into capillaries for exchanges with tissue fluid
Rhythmic pulsatile movements of the heart pump and circulate the blood in the body
For nutrients, gaseous and etc. exchanges with the tissue fluid.
Mammalian Cardiovascular System
2 atria, 2 ventricles
After the blood passes through the right atrioventricular valve, the right ventricle pumps the blood to pulmonary semilunar valve into the pulmonary trunk and pulmonary arteries to the lungs.
Pulmonary veins bring O2-rich blood back to the left atrium
After the blood passes through the left atrioventricular valve , the left ventricle pumps the blood to aortic semilunar valve into the aorta then to the tissues
70 times a minute
all chambers rest
Systole refers to contraction, diastole is relaxation
cardiac conduction system:
The SA node initiates the heartbeat (cardiac pacemaker)
Arteries - carry blood away from the heart to the capillaries
Capillaries - permit exchange of material with tissues
Veins - return blood from the capillaries to the heart
The Pulmonary Circuit
portion of the cardiovascular system which carries deoxygenated blood away from the heart, to the lungs, and returns oxygenated (oxygen-rich) blood back to the heart. The term pulmonary circulation is readily paired and contrasted with the systemic circulation.
The Systemic Circuit
carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart.
measured on the brachial artery of the upper arm
- ventricular systole
- ventricular diastole
accounts for the flow of blood from the heart to the capillaries
Venous return depends upon three factors:
Skeletal muscle contraction
presence of valves in veins
Hypertension is often seen in individuals who have atherosclerosis
plaques intrude the flow of blood
stationary clot (thrombus)
clot move with blood (embolus)
stroke - when a small cranial arteriole bursts or is blocked by an embolus
Heart attack - when a coronary artery is completely blocked
No Drug Abuse
Prevent Weight Gain
transport of nutrients
transport of metabolites
transport of excretory products
transport of gases
transport of hormones
transport of cells of non-respiratory function
transfer of heat
transmission of force
Type of Blood
Hematopoietic cells produce cells that become the various types of blood cells.
erythrocytes trantport haemogloblin
leukocytes and lymphocytes fight infections
neutrophil engulf foreign material
Basophil (parasitic infection and allergy)
eosinophil (combat parasites, allergy responses and asthma)
monocytes (phagocytizing cells)
platelets (blood clotting)
Heamophilia( failure of blood clotting)
Fat absorption and transportation from the digestive system
Primary lymphoid organ
bone marrow and thymus
Secondary lymphoid organ