BIOLOGY 336 STUDY TEST FOR TEST #2
(ANSWERS LISTED BY NUMBER AT BOTTOM OF EACH PAGE)
In the heart, the ventricular tissue that runs down the middle separating the right and left halves is called the 1 .
The tissue that lies horizontally between the atria and ventricles is made up of non-contractile tissue embedded with valves. Other walls of the heart are made up of 2 .
The 3 valve is located between the left atrium and left ventricle. It is also known as the 4 valve because it has two flaps. The 5 valve is located between the right atrium and the right ventricle (hint: it has 3 flaps).
The largest artery, the 6 , exits from the 7 . (This ventricle has walls that are about three times thicker than those of the right ventricle.)
Two large branches of veins dump blood into the right atrium; these are known as the 8 and the 9 .
The pulmonary artery splits into two branches; each branch goes to one of the two lungs. The pulmonary artery exits from the 10 .
The valve that opens to allow oxygenated blood to be pumped to the body is known as the 11 , which is located in the left ventricle. The valve that opens to allow deoxygenated blood (blood low in oxygen and high in carbon dioxide) to be pumped to the lungs is known as the 12 , located in the right ventricle.
Newly-oxygenated blood leaving the lungs enters the left atrium via the 13 .
So, in summary, blood must pass through the lungs before entering the left side of the heart. The right side of the heart pumps blood to the lungs, and the left side pumps blood to the body's tissues.
1. septum 2. muscle cells 3. mitral 4. bicuspid 5. tricuspid 6. aorta 7. left ventricle 8. inferior vena cava 9. superior vena cava 10. right ventricle 11. aortic valve 12. pulmonic valve 13. pulmonary veins
The1 node is also known as "the pacemaker," because it spontaneously depolarizes about 1 x per second without nerve impulses. Its location is in the upper part of the right atrium, and its resting potential is -80 mv.
Because of openings in the cells known as 2 , waves of depolarization radiate outward from the SA node and continue radiating throughout the cells in the atria, causing them to contract. These impulses spread at the rate of about 3 per second (which is slow in comparison to other impulses which spread at the rate of about 10-100 meters per second).
Once the wave (impulse) reaches the cartilage ring, it sits in the 4 for approximately one-tenth second (conduction velocity here is very slow, about .1 meters per second). A thin strip of conductive tissue known as the 5 sends the impulse down through the cartilage ring after it is held in the AV node. The Bundle of His then splits into the 6 and 7 . The impulse then travels along these branches very fast and spreads through the 8 , the result being a very strong, synchronized contraction of the two ventricles.
The impulse delay at the AV node enables the 9 to fill with blood.
The first wave of an EKG tracing, the 10 wave, is representative of the 11 in the process of contracting. The very beginning of this wave is indicative of the 12 depolarizing. The space of time between the occurrence of the P wave and the QRS complex is representative of 13 . The QRS complex represents 14 contraction. The 15 wave is an indication that the ventricles are relaxing. The voltage represented by the tracings is directly related to the number of cells depolarizing. (Note that the contraction of the ventricles produces a higher peak than the contraction of the atria. Since the ventricles make up about 80% of the total heart tissue and the atria make up about 20%, the ventricles will register higher voltages.)
A longer than usual tracing between the end of the P wave and the beginning of the QRS complex means that the impulse is being held for a longer period of time in the AV node; this is called 16 . A wider span between the Q and S waves are representative of a condition known as 17 . A series of high, rounded, irregular-appearing tracings on an EKG are representative of 18 .
1.SA node 2.gap junctions 3.one meter 4.AV node 5.Bundle of His 6.left bundle branch 7.right bundle branch 8.Purkinje fibers 9.ventricles 10.P 11.atria 12.SA node 13.the impulse being held in the AV node 14.ventricular 15.T 16.AV block 17.Bundle branch block 18.premature ventricular contraction
The two heart sounds are caused by the closing of heart valves. The first sound (S-1 or "lub") is caused by the closing of the 1 valves. The second sound (S-2 or "dup") is caused by the closing of the 2 valves. There are two things that can go wrong with valves. 3 is said to occur when the valve is rigid and doesn't open all the way. 4 is said to occur when the valve is leaky and doesn't completely block blood flow.
The largest artery in our body, the aorta, is approximately
5 in diameter. The arteries are made up of a 6 or hollow, lined on the inside by an 7 layer (very thin), and surrounded by many layers of 8 and 9 . The walls of arteries are very thick. Arteries can change shape because of the smooth muscle; they can contract or 10 , and they can relax, or 11 . The stretching and contracting alternating movements (pulse) of the smooth muscles are what moves the blood flow. Gas and food exchange occurs at the level of the 12 . Capillaries are made up of 13 tissue.
Blood pressure: blood pressure is very high near the 14 and other arteries, and much lower in the 15 . At the aorta, blood pressure is approximately 16 mmHg; in the right atrium, blood pressure is almost 17 .
Veins have very 18 walls compared to arteries, with very little 19 tissue and virtually no 20 . Veins contain many 21 that help keep blood moving in one direction. (Another mechanism by which the blood moves is the contraction of muscles against the veins, which squeezes the veins and helps push the blood along.)
The heart rate of a normal human at rest is about 22 beats per minute. The 23 is the volume of blood given out per beat. The average amount of blood given out per beat (stroke volume) is about 24 ml.
Average cardiac output: Q = 60 beats per minute x 100 ml per beat, which equals 6000 ml per minute or 25 per minute. Maximum cardiac output is based on maximum beats per minute which is approximately equal to 220 beats per minute minus an individual's age. Therefore, a normal 20-year-old is able to have a heart rate of up to 200 beats per minute (220-20) and a total cardiac output of 200 b.p.m. x 100 ml per beat or 20,000 ml per minute (that's 20 liters per minute!!). To summarize, a normal 20-year-old human being can have a cardiac output ranging from 6 to 20 liters per minute.
1. AV valves 2. aortic and pulmonic 3. Stenosis 4. Insufficiency 5. one inch 6. lumen 7. endothelial 8. smooth muscle 9. elastic tissue 10. vasoconstrict 11. vasodilate 12. capillaries
13. endothelial 14. aorta 15. veins 16. 120 17. 0 18. thin 19. elastic 20. smooth muscle 21. one-way valves 22. 60
23. stroke volume 24. 100 25. 6 liters
1 states that blood pressure is a function of two things: cardiac output (flow) and vascular resistance. The formula is Pressure (P) = Q x TPR. TPR stands for 2 . Both TPR and cardiac output are 3 to blood pressure. Constriction of a vessel (making the opening through which the blood flows smaller) increases resistance, therefore increasing blood pressure. Radius is inversely proportional to resistance (see formula on left). Because of this relationship of radius to resistance, small reductions in radius result in 4 in resistance. Peripheral vasal dilators are 5 blockers. An example of one of these is 6 . Also, the higher the temperature, the more the vessels will 7 .
Normal blood pressure is 8 . The first sound heard through a stethoscope is the 9 blood pressure and the second sound is the 10 blood pressure.
The 11 is the percentage of red blood cells in the blood. For men this is 12 percent and for women it is 13 percent. 14 is an iron-containing protein inside red blood cells that carries large amounts of 15 .
Heart disease: 16 is caused by lack of oxygen in the heart circulation due to 17 blockage (plaque formation). Risk factors for coronary heart disease could be lowered by 80% if a person stopped 18 , lowered their 19 , and lowered their 20 .
The SA node spontaneously depolarizes at the rate of about 60 times per minute. Other myocardial cells have a resting potential of 21 mv. Before the cell reaches threshold, the change from negative to less negative is called its 22 . A steeper pre-potential results in a faster action potential, and therefore, a faster 23 . The SA node spontaneously depolarizes at the rate of 60 times per minute, but it can speed up or slow down depending on the action of two major Central Nervous System nerves. The 24 nerve inhibits or slows the SA node down and the 25 nerve excites or speeds it up. Stimulation of the vagus nerve causes the pre-potential to rise more slowly, thus resulting in a net effect of decreased heart rate. The cardiac nerve, then, causes the pre-potential to rise more quickly, thus resulting in a net effect of increased heart rate.
1. Ohm's Law 2. Total Peripheral Resistance 3. directly proportional 4. very large increases 5. CA++ (calcium)
6. vorapromil 7. dilate 8. 120/80 9. systolic 10. diastolic 11. hematocrit 12. 40-45 13. 35-40 14. Hemoglobin 15. oxygen 16. Myocardial infarction 17. coronary artery 18. smoking
19. blood pressure 20. cholesterol 21. -80 22. pre-potential
23. heart rate 24. vagus 25. cardiac
What function do these changes in heart rate caused by vagus and cardiac nerve stimulation have in regulation of blood pressure? Small receptors called 1 located in the carotid artery sense blood pressure. These send messages to the central nervous system, after which either the vagus or cardiac nerve get stimulated, depending on which way the blood pressure needs to be regulated. Example: Blood pressure drops. Baroreceptors sense this drop, send message to the 2 , which in turn stimulates the 3 nerve to increase the heart rate. In addition, the smooth muscle cells of the blood vessels 4 , thus increasing resistance. The result of these changes is that blood pressure goes back up. Therefore, control of blood pressure is regulated through vessel changes (constriction/ dilation) and heart rate (increase/ decrease of flow). Also, when vaso-dilation occurs in one place, vaso-constriction must occur in other places in order to keep blood pressure balanced.
Our body weight is composed of about 5 % water. Blood plasma is composed of about 90% water and large proteins. Water molecules are small and can move easily across the capillary walls, which are semi-permeable. There are two forces that move water across the capillary walls: 6 pressure, in which water moves from areas of higher pressure to areas of lower pressure, and 7 pressure, in which water is drawn to large plasma proteins that stay inside the capillaries. On the arteriole side of the capillary the blood pressure is about 8 . This causes 40 water molecules to go out of the capillaries into the interstitial space (hydrostatic pressure). At the same time, the plasma protein concentration causes 9 water molecules to flow into the capillaries from the interstitial space. The net loss of water inside the capillaries is 15. Over on the venous side, the blood pressure has dropped to about 10; therefore, 10 water molecules go out of the capillaries. The concentration of the plasma proteins in the blood remains the same on the venous side as it was on the capillary side; thus, 25 water molecules come in. This results in a 10 inside the vessels on the venous side. Actually, the previous exact net offset of water filtration and reabsorption is a simplistic account. In reality, about 1% more water remains in the 11 . This water is picked up by the 12 which dumps the fluid back into the blood via the 13 .
1. baroreceptors 2. central nervous system (CNS) 3. cardiac
4. contract 5. 60 6. hydrostatic 7. osmotic 8. 40 9. 25
10. net gain of 15 water molecules 11. interstitial space
12. lymphatic system 13. superior vena cava
The swelling caused by excess fluid in interstitial space is known as 1 . There are three reasons why edema might occur: there might not be enough 2 in the vessels, the 3
might be too high, or the 4 might be blocked. 5 is a disease caused by lack of plasma proteins; one of its symptoms is edema. High blood pressure forces more water out of the plasma contained in the vessels into the interstitial space, resulting in more going out than is coming back in. A common problem often caused by high blood pressure is 6 . Disruption of the lymphatic system can be caused by removal of lymph ducts. Blockage of the lymph system can also be caused by infestation of the lymph system by a parasite. This disease is known as 7 . 8 , or chronic edema, is caused by a blocked lymphatic system.
Respiratory System The nasal and oral cavities are the routes through which we inspire and expire (inhale and exhale). At sea level, the barometric pressure is about 9 mmHg. The nasal and oral cavities lead to the 10 which is wrapped in 11 rings. The trachea splits into two parts: 12 . These 2 bronchial passages split and split and split. In humans there are 13 generations of bifurcations. The generations numbered 1-16 are known as the 14 . These are made of 15 and have the capability of 16 and 17 . They conduct air to the alveoli. Generations numbered 17-23 are known as 18 . These contain blind sacs, or alveoli that are 19 thick. These alveoli have no 20 and there are approximately 300 million of them in a healthy set of lungs. Asthma is a result of 21 ; therefore, treatment for asthma consists of administration of 22 .
The lungs are enclosed in the 23 cavity. At the bottom of the thoracic cavity is located the 24 which is concave at rest. The middle of the thoracic cavity is divided by the 25 which separates the left lung and the left thoracic cavity from the right. The space outside the lungs within the thoracic cavity is called the 26 space. This space is relatively small and the barometric pressure inside it is 27 . This is 5 less than the atmospheric barometric pressure at sea level and the barometric pressure inside the lungs. As you go up higher in the atmosphere, the barometric pressure goes 28 . The pressure inside the lungs is called the 29 pressure. Pressure is inversely proportional to 30 (P = 1/v)
1. edema 2. plasma proteins 3. blood pressure 4. lymphatic system 5. Kwashiorkor 6. pulmonary edema 7. filariasis
8. Elephantiasis 9. 760 10. trachea 11. cartilage 12. the left and right main bronchi 13. 23 14. conducting bronchial tubes 15. smooth muscle 16. constricting 17. dilating
18. respiratory bronchioles 19. one-cell 20. smooth muscle
21. bronchial constriction 22. bronchial dilators 23. thoracic 24. diaphragm 25. mediastinum 26. intra-plural space 27. 755 28. down 29. intra-pulmonary 30. volume
When an action potential occurs, it causes the diaphragm to 1 , thus causing it to move 2 . Even though the lungs and the chest wall and the lungs and diaphragm are not attached, the lungs move downward with the diaphragm when the diaphragm contracts. This is due to the fact that the organs and muscles contained within the thoracic cavity are in a closed system; the movement downward of the diaphragm creates a 3 that causes the lungs to move downward also. This stretching of the lungs increases their volume, thus lowering the barometric pressure inside, causing air flow to go in the direction of the 4 . (Pressure moves from high to low until the lung pressure is equal to atmospheric pressure.)
The lungs are coated with elastic material. They naturally want to spring down or push together; therefore, 5 is needed to make them expand. This energy is in the form of action potentials. So, to conclude, inspiration requires 6 , whereas expiration requires 7 . The system works together in the following way in a normal, healthy body: the chest wall "wants to" 8 , and the lungs "want to" shrink down. These keep each other in balance. However, cigarette smoking destroys the elasticity in the tissue, thus ruining this balance. 9 is a disease in which the chest wall and lungs are stretched out.
The condition of air getting into the thoracic cavity is called 10 . Air will rush in when the system is punctured because intra-plural space has a pressure of 755, 5 less than the atmosphere. 11 is a rupture of the lung. This allows air to go into intra-plural space without the thoracic cavity getting punctured.
The 12 is the maximal amount of air inspirated plus the maximal amount of air expirated. The 13 is the amount of air remaining after you let out the maximal expiration. The total lung volume is equal to 14 and 15 . The residual volume prevents 16 . Air is exchanged from 70 square meters of 17 surface to 70 square meters of 18 surface. The respiratory rate of humans at rest is about 19 per minute. The amount of air going in and out per breath is known as the 20 . This is about 21 ml for humans at rest. The minute volume for humans at rest is 12 breaths per minute x 500 ml per breath which is 6000 ml/min or 6 liters per minute. The minute volume is variable; for instance, it goes up as the amount of activity increases.
1. contract 2. outward (expand) 3. vacuum 4. alveoli
5. energy 6. action potentials 7. cessation of action potentials 8. expand 9. Emphysema 10. pneumo-thorax
11. Pleurisy 12. vital capacity 13. residual volume 14. vital capacity 15. residual volume 16. the alveoli from collapsing 17. alveoli 18. capillary 19. 12-15 breaths 20. tidal volume 21. 500 ml (1/2 Liter)
The air we breathe is composed of about 21% 1 , .03% 2 , and 79 % 3 . The law of partial pressure says that the pressure of a certain gas is equal to the percentage of this gas's concentration times the barometric pressure. So, PO2 = 760 mmHg. x .21 or 160 mmHg. Both the nasal cavity and trachea are lined with mucous membranes which contain 4 . Therefore, lungs contain water vapor in addition to all the other gas components of air. The pressure caused by O2 in lungs is calculated as follows:
760 total barometric pressure
-47 H2O (Constant)
713 pressure remaining
x.145 percentage of O2 concentration in lungs
Using this calculation, the pressure in the lungs is roughly 5 mmHg. The pulmonary artery brings in venous blood (depleted of O2). The PO2 of this blood is about 6 mmHg. Since the PO2 in the lungs is always about 100 because we are constantly breathing in air, the O2 gets pushed out of the alveoli as the blood passes. Oxygen gets pushed out into the blood until the oxygen pressure there is equal to that of the 7 . At the cellular level, the PO2 is about 8 mmHg. O2 from the blood then goes across to the cell until the blood's PO2 becomes 40 mmHg. The gas exchanges of both O2 and CO2 in the body are caused by 9 .
When an individual is at a high altitude, it is very difficult to breathe (the air is "thin"). The reason why this is so is because as you go up in altitude, atmospheric barometric pressure goes down. For instance, in a very high altitude, the barometric pressure might be 240. Using the formula of the law of partial pressure, the following numbers would emerge:
240 mmHg. barometric pressure (atmosphere)
-47 (Water - constant)
197 mmHg. pressure remaining
x.145 percentage of oxygen
The resulting amount would be less PO2 in the lungs than there would be in the pulmonary artery. The main result of this would be 10 . One way to try to combat this would be to 11 .
1. oxygen (O2) 2. carbon dioxide (CO2) 3. nitrogen 4. water 5. 100 6. 40 7. lungs 8. 40 9. the partial pressure gradient of these gases 10. no gas exchange and no oxygen into the blood 11. hyperventilate
EXCHANGE OF CARBON DIOXIDE (CO2) PCO2 in the lungs is about 1 mmHg, and the PCO2 in the blood is about 2 . As the blood gets to the alveoli, CO2 is dumped out of the blood and O2 is brought in. At the cellular level, CO2 is brought into the blood and O2 is dumped out. As O2 diffuses across the capillaries to the cell, the PO2 inside the cell when the cell is at rest stays relatively 3 because the cell is always using energy.
4 says that diffusion of gas is affected by three things: 5 , 6 , and 7 .
The first two factors (pressure and area) are 8 proportional to diffusion and the last factor (distance or length) is 9 proportional to diffusion. In the case of pulmonary edema, 10 accumulates between the alveoli and the pulmonary cavity. This has the effect of 11 and thus 12 . Emphysema destroys the alveoli, thus decreasing 13 and decreasing 14 . The treatment for emphysema is to give pure O2 air; this increases the alveolar PO2. The only thing that would affect the pressure part of the equation is 15 .
Blood pressure is very different from barometric pressure. Coming out of the left ventricle (aorta), the blood pressure is about 16 . At the cellular level it's about 17 . After going past the cell, it's about 18 . At the right atrium it's nearly 19 . At the lung site, it's about 20 .
The oxygen consumption of humans at rest is about 300 ml/min. During exercise, the VO2 is about 21 .
22 transports O2. The amount of O2 that hemoglobin carries depends on the 23 . At the lung site, the hemoglobin molecules get saturated at about 24 percent; however, only about 25 percent gets dumped off at the cells. This allows for 26 when we need it. Anemia is caused by lack of iron due to lack of hemoglobin. At a PO2 of 100, hemoglobin molecules are 27 saturated.
How do we know how much to ventilate? Chemoreceptors in the 28 artery sense the PO2, and chemoreceptors in the 29 sense PCO2. These chemoreceptors then send messages to the 30 to regulate breathing. When carotid chemoreceptors sense high PO2, breathing 31 ; when the chemoreceptors in the medulla sense high PCO2, breathing 32 .
1. 40 2. 46 3. the same 4. Fick's law of diffusion 5. change in pressure 6. change in cross-sectional area 7. change in length (distance the gas must move) 8. directly 9. inversely 10. interstitial fluid 11. increasing length 12. decreasing diffusion 13. cross-sectional area 14. diffusion
15. environmental conditions 16. 120 17. 40 18. 10 19. 0
20. 20 21. 2-4 Liters per minute 27. Hemoglobin 23. PO2
24. 98 25. 25 26. immediate oxygen supply 27. maximally 28.carotid 29.medulla 30.respiratory center 31.slows 32.increases