Lecture 23: Anatomy and Physiology II (blood/cardiovascular) Flashcards
What does the body contain and what are they called?
Red blood cells that are called erythrocytes
What is the shape of RBC?
Biconcave disk that increases surface area for gas exchange, places cell membrane closer to hemoglobin. Also, as they mature, they lose their nuclei for more oxygen as well as mitochondria
What happens when RBC lose their nucleus?
There is no DNA and they cannot produce cell division or protein synthesis.
What happens when RBC lose their mitochondria?
They cannot perform cellular respiration and instead only glycolysis and do not use the oxygen that they carry
What are hemoglobins?
Protein complexes that bind to oxygen
What is heme?
The red pigment that contains iron and binds to oxygem
What is globin?
A 4 part protein complex that binds to carbon dioxide
What gives RBC their red color?
hemoglobin
What is oxyhemoglobin?
It is when hemoglobin binds to oxygen and this is bright red in color
What is deoxyhemoglobin?
It is when hemoglobin does not bind to oxygen and instead is a dark red color. An example are veins where they appear blue and filters the red color
Where are new red blood cells made?
Red bone marrow in adults and this is known as erythriopoiesis
Where are RBC produced from?
Hematopoietic stem cells that are triggered by erythripoeitin by the kidneys and liver in response to oxygen deficiency
What is needed to make more RBC?
Dietary needs like B-complex like B12 and folic acid for DNA synthesis. Also, iron for hemoglobin synthesis.
What is the first step in RBC destruction?
- they circulate in the body for 120 days
- macrophage destroy the RBC and this occurs in the liver and spleen
What happens after the macrophage destroy the RBC? Second step.
- The hemoglobin is broken down into amino acids and iron to be recycled
What happens when the amino acid is broken down and recycled? Third step.
Heme decomposes into biliverdin (green) and bilirubin(yellow) pigment and is released as bile pigments
What is the last step in RBC destruction?
Degraded pigment leaves as stercobilin(brown) and urobilin(yellow)
What is the epicardium?
It is the outer layer and it means “on the heart”. It is also a part of the pericardial to protect the heart from friction.
What is the myocardium?
It is the cardiac muscle and it is the middle layer that means the “muscle heart”
What is the endocardium?
It is the inner layer and it means “inside the heart”. It also contains the purkinje fibers.
What is the atria?
It is the upper chambers and mean “the entryway”.
What does the atria do?
They receive blood returning to the heart.
What are auricles?
They mean “small ears” and and are part of the atria to increase atrial volume
What are the ventricles?
They are the lower chambers and it means “underside”
What do the ventricles do?
They receive blood from the atria and contract to force blood out
What is the septum?
They separate right and left sides of the heart basically in the middle
How does blood flow begin? First step?
Blood returns to the right atrium(this is deoxygenated blood).
- Superior vena cava: deoxygenated blood from upper body
- Inferior vena cava: deoxygenated blood from lower body
- Coronary sinus: deoxygenated blood from the heart
How does blow flow? Second step?
When the atrium contracts, blood is pumped into the right ventricle
- passes through the tricuspid valve
- 3 cusps close to prevent backflow
- chordae tedineae hold tricuspid valve inside ventricle
How does blow flow? Third step?
Blood is pumped from right ventricle to pulmonary circuit
- passes through pulmonary semilunar valve
- passes through the pulmonary trunk
- passes through the pulmonary arteries(left/right)
- deoxygenated blood travels to the lungs
How does blood flow? Fourth step?
Blood returns to the heart via the left atrium
- oxygenated blood return via 4 pulmonary veins
How does blood flow? Fifth step?
Blood is pumped from the left atrium to left ventricle
- passes through bicuspid valve (mitral valve)
- chordae tendineae hold mitral valve inside ventricle
How does blood flow? Sixth step?
Blood pumped from left ventricle to systemic circuit
- passes through aortic semilunar valve
- passes through aorta
What is the cardiac cycle?
The heart beating
What is the systole?
The heart contraction
What is the diastole?
the heart relaxation
What is the atrial systole?
It is when the atria contracts and the blood flow to the ventricles
What is ventricular systole?
It is when the atrial diastole and the ventricles contract while the atrial relaxes
What is the first heart sound?
The lubb and is the closing of the tricuspid and bicuspid valves
What is the second heart sound?
It is the dubb and is the closing of the semilunar valves
What is cardiac conduction system(the rhythm of heartbeat)?
The impulses travel through the heart to coordinate the cardiac cycle.
Where do the impulses start for cardiac conduction?
They start in the sinoatrial located beneath the epicardium in the right atrium.
What is the atrioventricular node?
It is located in the septum between atria and ventricles. It is where the impulses converge at AV node, small fibers conduct impulses slowly and delay transmission, and allows time for atria to contract before impulse is sent to ventricles. Eventually, impulses travel though AV bundle. There are also separate left and right bundle branches
How does blood flow?
- arteries carry blood away from the heart
- arteries branch out into thinner arterioles
- arterioles branch out into thinner capillaries
- capillaries are where there is exchange in gas, nutrients, and metabolic waste with tissues
- capillaries converge into thicker venules
- venules converge into thicker veins
- veins carry blood toward the heart
What happen to blood flow in the veins?
1.Skeletal muscle contraction compresses the blood fluid that causes the valves to and let blood flow to the heart.
- The cusp shape of the valves catches backflow which closes the valves preventing blood from flowing backwards
What is blood pressure?
The force per unit area exerted on a vessel wall in mmHg
What is the systolic pressure?
Pressure of blood pumping when ventricles contract
What is the diastolic pressure?
The pressure of blood flowing when ventricles relax
What is the mean arterial pressure?
MAP=SP+2DP/3
