[Biology] Ch. 7: The Cardiovascular System Flashcards
What are the major components of the cardiovascular system
Four-chambered heart, blood vessels, and blood
The heart is composed predominantly of
Cardiac muscle
The right side of the heart accepts [ 1 ] blood returning from the body and moves it to the [ 2 ] by way of the [ 3 ]
1) deoxygenated 2) lungs 3) pulmonary arteries
The left side of the heart receives [ 1 ] blood from the [ 2 ] by way of the [ 3 ] and forces it out to the body through the [ 4 ]
1) oxygenated 2) lungs 3) pulmonary veins 4) aorta
What are the two forms of circulation in the heart
Pulmonary circulation and systemic circulation
The atria are [ 1 ] structures where the blood is received from either the [ 2 ] or the [ 3 ]
1) thin-walled 2) venae cavae 3) pulmonary veins
What’s the difference between the vena cavae and the pulmonary veins
Venae cavae = deoxygenated blood pulmonary veins = oxygenated blood
The atria contract to push blood into the [ 1 ]
Ventricles
After the ventricles fill they contract to send blood to the [ 1 ] and [ 2 ]
1) lungs 2) systemic circulation
Why are ventricles much more muscular than the atria
To allow for more powerful contractions necessary to push blood through the rest of the cardiovascular system
Recite the mnemonic to remember the atrioventricular valves
LAB RAT
- Left Atrium = Bicuspid valve
- Right Atrium = Tricuspid valve
What is the name of the valves that separate the ventricles
Semilunar valves
The right ventricle feeds into [ 1 ] and the left ventricle feeds into [ 2 ]
1) pulmonary circulation 2) aorta / systemic circulation
What are the two valves associated with the ventricles
The pulmonary valve and the aortic valve
What are the four electrically excitable structures that coordinate the rhythmic contraction of cardiac muscle (in order)
The sinoatrial node (SA), the atrioventricular node (AV), the bundle of His (AV bundle) and its branches, and the Purkinjie fibers
Impulse initiation in the heart doesn’t require [ 1 ]
Neurological input
Depolarization from the [ 1 ] causes the two atria to contract simultaneously
SA node
Muscle cells in the heart are connected by [ 1 ] which contain many gap junctions directly connecting the [ 2 ] of adjacent cells, thereby allowing for coordinated [ 3 ]
1) intercalated discs 2) cytoplasm 3) ventricular contraction
What is the role of neurological input to heart contraction
It’s important in speeding up and slowing down the rate of contraction (but not generating it in the first place)
What is the difference between the sympathetic and parasympathetic effect on the speed and contractility of cardiac muscle
- Sympathetic = signal speeds up the heart rate and increases contractility
- Parasympathetic = slows down heart beat
What is the difference between systole and diastole
- Systole = ventricular contraction, closure of the AV valve, blood pumped put of the ventricles
- Diastole = heart is relaxed, semilunar valves close, blood from the atria fills the ventricles
What would happen if large arteries didn’t have elasticity
Diastolic blood pressure would plummet to zero
What is cardiac output
It’s the total blood volume pumped by a ventricle in a minute
What is cardiac output a product of
Heart rate (beats per minute) * stroke volume (volume of blood pumped per beat)
What are the three major types of blood vessels
Arteries, veins, and capillaries
Why are all blood vessels lined with endothelial cells
- They help maintain the vessel by releasing chemicals that aid in vasodilation and constriction
- Allow white blood cells to pass through the vessel wall and into tissues during inflammatory response
- They release certain chemicals when damaged that are necessary in the formation of blood clots to repair the vessel and stop bleeding
What is the main structural similarity and difference between veins and arteries
Similarly = made of the same types of cells, difference = smooth muscle and thin veins
What are the two kinds of arteries that carry deoxygenated blood
Pulmonary arteries and umbilical arteries
Why is the left side of the heart thicker than the right side of the heart
left heart must generate much higher pressure to overcome the resistance from systemic arteries
The thin walls of the capillary allows easy diffusion of [ 1 ], [ 2 ], and [ 3 ]
1) gases 2) nutrients (most notably, glucose) 3) wastes
Why do larger veins contain valves
As blood flows forward in the veins the valves open and when blood tries to move backward the valves will slam shut
What causes varicose veins
When venous valves fails
What’s the relation between veins and skeletal muscle
Skeletal muscles squeeze the veins when they contract
The superior vena cava returns blood from portions of the body [ 1 ] the heart while the inferior vena cava returns blood from portions of the body [ 2 ] the heart
1) above 2) below
By volume blood is [ 1 ] % liquid and [ 2 ] % cells
1) 55 2) 45
What is blood plasma
It’s the liquid portion of blood (aqueous mixture of nutrients, salts, respiratory gases, hormones, and blood proteins
What are the three major cellular components of blood
Erythrocytes, leukocytes, and platelets
Why is there low solubility of molecular oxygen
Because it’s nonpolar
What is the benefit of the shape of red blood cells
Help traveling through tiny capillaries + increased surface area for gas exchange
Why are red blood cells unable to carry out oxidative phosphorylation to generate ATP. Why do they rely mainly on glycolysis for ATP
Because they lose mitochondria when they mature
What are erythropoietin and thrombopoietin
Hormones that trigger hematopoiesis
What does erythropoietin do and where is it secreted from
- Stimulates red blood cell development
- Secreted by the kidney
What does thrombopoietin do and where is it secreted from
- Stimulates platelet development
- Secreted by the liver
What do red blood cells display on their surface
Antigens
What do people with type O blood express on their cell surface
Nothing; no antigens
Which blood type is a universal donor and which type is a universal acceptor
- Universal donor = O blood type (produces antibodies against everything but has no antigens to licit an immune response)
- Universal acceptor = AB blood type (makes no antibodies to anything)
Rh-positivity follows [ 1 ] inheritance and one positive allele is [ 2 ]
1) autosomal dominant 2) enough for the protein to be expressed
When is Rh factor status particularly important
In maternal-fetal medicine
What is blood pressure a measure of
force per unit area exerted on the wall of the blood vessels
What do you measure blood pressure with
Sphygmomanometer
How is blood pressure regulated
Using baroreceptors in the walls of the vasculature
Does the cardiovascular system have an effective way of decreasing blood pressure
No
Why isn’t atrial natriuretic peptide (ANP) effective at lowering blood pressure
It’s a weak diuretic
What is oxygen saturation
The percentage of hemoglobin molecules carrying oxygen
Why isn’t CO2 carried by hemoglobin
Hemoglobin has a much lower affinity for CO2 than for oxygen
What is the main method to carry the CO2 in the blood
As the bicarbonate ion
What do right and left shifts in the oxyhemoglobin curve represent
Right shift = decrease in hemoglobin affinity, left shift = increase in hemoglobin affinity
How would the fetal hemoglobin graph look compared to the hemoglobin graph
It would be shifted left
If there’s a right shift in the hemoglobin curve what would be the implications of that
Decreased affinity of to hemoglobin allows more oxygen to be unloaded at the tissues
The bicarbonate buffer system links the [ 1 ] and [ 2 ] system
1) respiratory 2) renal
What is hydrostatic pressure
The force per unit area that the blood exerts against the vessel wall
What happens when the endothelium of a blood vessel is damaged
It exposes the underlying connective tissue that contains collagen and tissue factor (a protein)
When platelets come in contact with [ 1 ] they sense the evidence of injury
Exposed collagen
What do platelets do when they sense injury
They release their contents and begin to aggregate/clump together
What is the endpoint of the coagulation cascade
The activation of prothrombin to form thrombin by thromboplastin
[ 1 ] converts fibrinogen into fibrin which ultimately forms [ 2 ], like a net, that captures red blood cells and other platelets forming a stable clot over the area of damage
1) Thrombin 2) small fibers that aggregate and cross link into a woven structure
What does plasmin do
degrades many blood plasma proteins, including fibrin clots
