Chapter 2 - Transport in Humans Flashcards
what makes up the cardiovascular system
- heart
- blood
- blood vessels
what does the cardiovascular system do
it is a transport system
- delivers oxygen and nutrients to cells
- removes carbon dioxide and waste products made by those cells
characteristics of blood
- heavier and thicker than water
- O2 content determines colour (less O2, darker)
- males (5-6L), females (4-5)
components of blood
- plasma 55% volume
- formed elements/cells 45%
-> rbc, wbc, platelets
what is the plasma
- pale, yellow liquid that surrounds cells
- 91% water, 7% proteins, 2% other
what are the plasma proteins
albumin, globulins, fibrinogen
what is albumin
- 58% plasma protein
- helps maintain water balance
what is globulins
- 38% of plasma proteins
- helps immune system
what is fibrinogen
- 4% of plasma proteins
- aids in clot formation
what are erythrocytes
- red blood cells
- disk shaped with thick edges
- transports O2 to tissues
- produced in bone marrow
- lose nuclei and mitochondria -> more space for hemoglobin (iron-containing protein that transports O2)
- lasts 3-4 months -> filtered out by liver; ard 3 million rbc destroyed each second
what is hemoglobin
- main component of erythrocytes
- transports O2
- each globin protein is attached to a heme molecule
- each heme contains one iron atom
- O2 bind to iron -> oxyhemoglobin
what are leukocytes
- white blood cells
- lack hemoglobin
- larger than erythrocytes
- contains a nucleus
- fight infections
- remove dead cells and debris by phagocytosis
what are the types of leukocytes
neutrophils, eosinophils, basophils, monocytes, lymphocytes
what are neutrophils
- 40-60% of wbc
- defend against bacterial or fungal infection
what are eosinophils
- deal with parasitic infections
- predominant inflammatory cells in allergic reaction
what are basophils
- short-term inflammatory response
- release histamine
what are monocytes
- large leukocytes
- differentiate into macrophages
what are lymphocytes
- immune response
- several different types (T and B cells -> produce antibodies)
- lead to the production of antibodies
what are platelets
- involved in blood clotting
- produced in red bone marrow
what is the production of blood cells like
- stem cells
-> “parent” cells in bone marrow
-> differentiate into many differentiate types of cells
steps in blood clotting
- injury to a blood vessel causes release of prothrombin activator
- prothrombin activator acts upon prothrombin
- prothrombin is switched to its active form thrombin
- thrombin activates fibrinogen into its active form fibrin
- fibrin forms a network that traps blood (clots)
what is the circulatory system
- supplies in fuels (sugars) -> digestive system
- supplies in oxygen -> respiratory system
- waste out (co2) -> respiratory system
- need to pick up and deliver the supplies and wastes around the body -> circulatory system
components of circulatory system
- organ
- heart - tissues and cells
- blood -> rbc
- blood vessels (vascular system) -> arteries, veins, capillaries
function of circulatory system
- regulates blood supply
- generates blood pressure
- routes blood
- ensures 1 way blood flow (heart valves)
characteristics of the heart
- size of a fist, weighs less than 1lb
- between lungs in thoracic cavity
- apex (bottom) towards left side
- 4 chambered (atria, ventricles)
4 chambers of the heart
- left and right atrium
- left and right ventricles
what is the coronary sulcus
separates atria from ventricles
components of atria
- upper portion
- holding chambers
- small, thin walled
- contract minimally to push blood into ventricles
interatrial septum - separates right and left atrium
components of ventricles
- lower portion
- pumping chambers
- thick, strong walled
- contract forcefully to propel blood out of heart
interventricular septum - separates right and left ventricles
atrioventricular valves
- between atria and ventricles
- tricuspid valve
- AV valve between right atrium and right ventricle
- 3 cusps - bicuspid valve (mitral)
- AV valve between left atrium and left ventricle
- 2 cusps
what is the chordae tendineae
- attached to AV valve flaps
- support valves
semilunar valves
- pulmonary
- base of pulmonary trunk - aortic
- base of aorta
function of blood vessels
- carry blood
- exchange nutrients, waste products, gases within tissues
- transport substances
- regulate blood pressure
- direct blood flow to tissues
layer of blood vessels: arteries, arterioles, venules, veins
characteristics of arteries
- blood flows away from heart
- thicker walls -> provide strength for high pressure pumping of blood
- elastic and stretchable -> maintains blood pressure even when heart relaxes
characteristics of veins
- blood returns back to heart
- thinner walls -> blood travels back to heart at low speed and pressure (lower pressure -> far from heart)
- blood flows because muscles contract when we move -> squeezes blood through veins
- veins in large veins -> in larger veins one-way valves allow blood to only flow toward heart
characteristics of capillaries
- very thin walls
- allows exchange of materials across capillary
function of capillary
- exchange between blood and tissues (o2, co2, h20, food, waste)
- blood flow in capillaries controlled by pre-capillary sphincter valves
capillary beds
- only 5-10% of bodys capillaries have blood flowing through them at any time
- supply varies as blood is needed:
-> after a meal, blood supply to digestive tract increases
-> during strenous exercise, blood is diverted from digestive tract to skeletal muscles - capillaries in brain, kidney, heart and liver usually filled to capacity
flow of blood
arteries, arterioles, capillaries, venules, small veins, heart
advantage of 4-chambered heart
- able to create more pressure to pump blood around the system
- separation of oxygen-rich and oxygen-poor blood
- caters for higher energy needs
-> greater need for energy, fuel, O2, waste removal
cardiac cycle
1 complete sequence of pumping
- heart contracts and pumps
- heart relaxes and chambers fill
systole = contraction phase
diastole = relaxation phase
process of cardiac cycle
- atria and ventricles are relaxed
- blood flows into heart
- atria contract simultaneously
- tricuspid and bicuspid valve open
- blood flows from atria to ventricles
- ventricles contract simultaneously
- tricuspid and bicuspid valves close
- semilunar vales open
- blood flows from ventricles out of heart
heart sounds
lub - when ventricles contract, the tricuspid and bicuspid valves snap shut
dub - when the ventricles relax and the pulmonary and aortic valves snap shut
arterial system
- carry oxygen rich blood away from the heart
- pulmonary arteries carry oxygen poor blood
venous system
- carries oxygen poor blood toward the heart (except for pulmonary veins)
pulmonary circuit
right atrium , right ventricles, pulmonary artery trunk, pulmonary arteries, lungs, pulmonary veins, heart
systemic circuit
left atrium, left ventricle, aorta, arteries, arterioles capillaries, venules, veins, vena cava, heart (right atrium)
