Bio 269 - Exam 2 study guide

Exam 2 Study Guide Answers

Cardiovascular II

Know the pulmonary and systemic circuit and the names of the blood vessels
that bring oxygenated and deoxygenated blood to and from each circuit.

Pulmonary Circuit
 Blood from heart to lungs; lungs back to heart
Right atrium (deoxygenated)  right ventricle  goes up blood vessels (pulmonary arteries;
deoxygenated) to lungs  arterial end of pulmonary capillaries (deoxygenated)  lungs 
venous end of pulmonary capillaries (oxygenated)  pulmonary vein (brings oxygenated blood
from lungs back to heart)

Systemic Circuit
 Blood goes to tissues; system wide (not including lungs)
Left atrium receives oxygenated blood from lungs  left ventricle  brings oxygenated blood
to rest of body (aorta)  aorta branches into smaller arteries  arterioles  arterial end of
capillaries (oxygenated)  tissues (cells)  venous and (going back towards the heart) of
capillaries (deoxygenated)  veins  bring deoxygenated blood back to right atrium (2 vena
cavae [attaches both superior and inferior])

REMEMBER: glucose + oxygen = carbon dioxide + water + ATP




*this diagram is probably on exam

,Understand the architecture of heart, the names of the chambers, which
chambers carry oxygenated and deoxygenated blood, and the names of the
valves separating the chambers.

The heart is only made up of 1 type of cell (muscle cell)

Three-dimensional hollow mass of muscle
 Heart is suspended in a fluid called the pericardial sac
 Sarcomeres criss cross (fibrous skeleton)
o Gives it a stronger structure (heart needs a stronger structure because it is
constantly contracting and relaxing

4 chambers of the heart:
 2 Atria (receiving)
o Thin muscle on walls (only have to pump blood to one spot [ventricles; right next
to atria]; go with gravity)
o Right atrium: receives de-oxygenated blood from the body
o Left atrium: receives oxygenated blood from the lungs
o Atria contract more quickly than ventricles
 2 Ventricles (pumping)
o Bigger than atria (need more muscle to pump the blood farther)
o Right ventricle: pumps de-oxygenated blood to lungs
-Has 2nd highest muscle mass (pumps blood up to lungs)
o Left ventricle: pumps oxygenated blood to rest of body
-Has most muscle mass (pumps blood out of aorta into systemic circuit)

Artery: a blood vessel that carries blood away from the heart
-NOT always oxygenated (pulmonary artery carries deoxygenated blood)
Vein-: a blood vessel that brings blood towards the heart
-NOT always deoxygenated (pulmonary vein carries oxygenated blood)

Chambers and Carrying Blood
 Right atrium = deoxygenated
Left atrium = oxygenated
Right ventricle = deoxygenated
Left ventricle = oxygenated

AV valves (atrioventricular valves; 2) separate the chambers (the atria and the ventricles)
 Closing the valves separates blood from the atria and the ventricles
 Right AV valve = tricuspid
 Left AV valve = bicuspid (mitral valve)

,Semilunar valves (2)
 Right = pulmonary valve
o Separates pulmonary trunk from right ventricle
 Left = aortic valve
o Separates left ventricle from aorta

Immediately surrounding the heart is a very thin layer of connective tissue
 Pericardium (thin walled membrane surrounding the heart)
 Heart is suspended in pericardial fluid called Pericardial Sac
o Pericardial fluid is important because lungs and heart push up/rub against one
another as they contract/relax, fluid is a cushioning/protective layer for heart
between it and lungs
o Incompressible

Know the layers of the heart wall.

Pericardium- thin membrane that surrounds heart
 NOT part of heart wall, immediately surrounds heart

Epicardium- outer layer of heart
 Epi: “covering”

Myocardium- thickest layer
 Myo: “muscle”

Endocardium- inner most layer
 Lines the chambers
 Endo: “within”

, Understand what is meant by the coronary circuit and the types of coronary
disease.

Coronary is the shortest circuit in the human body (systemic is longest)
-Supplies myocardium with blood

What is important to know about coronary circuit
 Aorta branches off to coronary arteries to supply blood flow to myocardium, venous
blood going back empties in to RA

 Coronary Disease: disease of blood vessels surrounding the heart
 Clots: form in vessels; deposits of fatty tissue that form over time; stick to one another
and to wall of vessel
o Constrict areas of blood vessels cells of heart don’t get enough oxygen and
nutrients  can’t make ATP  cells will die

Types of coronary disease:
 Angina Pectoralis
o Temporary halt of blood supply because not enough blood gets past the clots 
heart muscle does not get enough blood
o CURE: in order to pump blood past obstruction, wall (lined with smooth muscle)
starts to go into vascular spasm (contracts), there are nerve cells infiltrating the
blood vessels which send APs to brain (registers as pain), you get pills to lessen
pain and get rid of clots
 Myocardial Infarction (more serious; heart attack)
o Vessels are blocked to greater extent  stop most of blood from going to cells 
cells die from lack of nutrients/oxygen (not enough ATP)
o Heart attack: atria and ventricles beat/contract without rhythm  not enough
blood pumped to body  people collapse (not enough O2 to tissues)
o If you have 1 heart attack, the probability of you having another heart attack/other
heart problems goes up significantly and exponentially
o Amitotic cells don’t undergo mitosis  scar tissue is formed after heart attack and
is non-contractile
-Ex. 3 heart cells  1 dies  other 2 get larger  physical scar
-Ex. 100 cells  10% die off  90 left  for rest of life, 90 cells are
doing the job of what 100 used to do, under more pressure