Lab Practicum Exam 2 Flashcards
be able to label parts of the heart
(aorta, left atrium, left ventricle, right atrium, right ventricle, pulmonary trunk)
good luck!
the pericardium is a connective tissue covering that surrounds the heart in the thoracic cavity. It is made up of multiple layers. What is the sequence of the pericardial layers from most superficial to deep?
fibrous pericardium –> parietal pericardium –> pericardial cavity –> visceral pericardium
the valves that direct bloodflow from the atria to the ventricles are collectively called atrioventricular valves. However, each valve is also given a specific name. What is the name of the valve between the right atrium and right ventricle?
tricuspid valve
what is the name of the valve between the left atrium and the left ventricle?
mitral / bicuspid valve
True of False: (correct if not true)
The atrioventricular valves are physically connected to the wall of the ventricle through long cord structures called papillary cords that connect to muscles on the ventricular wall call chordae tendinae
FALSE - the atrioventricular valves are physically connected to the wall of the ventricle through long cord structures called CHORDAE TENDINAE that connect to muscles on the ventricular wall called PAPILLARY MUSCLE
deoxygenated blood enters the heart through the ________________ while oxygenated blood enters the heart through the _________________
vena cava, pulmonary vein
be able to identify the main locations of baroreceptors and the nerves that innerverate them on the image below
(glossopharyngeal nerve, aortic baroreceptors, carotid baroreceptors, vagus nerve)
you’ve got this!
short term blood regulation of blood pressure does not involve changes in which of the following?
- blood vessel diameter
- blood volume
- heart rate
blood volume
an increase in MABP will result in?
increased arteriolar diameter
which hormone: decreases water loss through the kidney
ADH
(antidiuretic hormone)
which hormone: increases sodium and water loss through the kidney
ANP
(atrial natriuretic peptide)
which hormone: increases sympathetic activity, increases water and sodium retention by the kidney, vasoconstriction of arterioles
RAAS
(renin-angiotensin-aldosterone system)
when stimulated by angiotensin II, what are the result(s) of the adrenal glands?
stimulates release of aldosterone
when stimulated by angiotensin II, what are the result(s) of the brain?
- resets the baroreceptor reflex
- increase in thirst
- stimulates release of ADH
when stimulated by angiotensin II, what are the result(s) of the kidneys?
- reduces salt and water excretion
- rise in extracellular fluid
provide a brief description of Starling’s Law of the heart
there is a relationship between ventricular stretch and the force of contraction. When stretch is increased, the force of contraction is increased
In today’s lab you saw the effects of 2 neurotransmitters on contraction of the heart. What were those 2 neurotransmitters AND which branch of the autonomic nervous system do they belong to?
- acetylcholine (parasympathetic nervous system)
- epinephrine (sympathetic nervous system)
Pilocarpine is a muscarinic receptor agonist. Based on this function, how do you expect this drug to effect heart rate?
decrease heart rate
Physiologically, the frog heart functions the same as the mammalian heart. Contraction mechanisms and electrical conduction pathways are the same. However, there is one large anatomical difference between the frog heart and the mammalian heart. What is the difference?
there is only one ventricle in a frog heart where there are 2 ventricles in the mammalian heart
How to calculate heart rate in beats per minute?
count the ECG beats for a fixed amount of seconds and multiply to get a total 60 seconds
How to calculate contraction force?
if the curves do not reach to zero, look at the force at the bottom of the curve and the top of the curve and subtract to get the total force
Compared to room temperature conditions, application of warm ringer’s solution ___________ heart rate while cold ringers solution ___________ heart rate
increased, decreased
be able to label the structures of the respiratory system
soooo easy!!
What is the name of the thin, dome-shaped, sheet of skeletal muscle at the base of the ribs that is responsible for increasing and decreasing the volume of the thoracic cavity during respiration?
diaphragm
Which statement regarding airflow resistance is false?
- an increased air density increases resistance to air flow
- resistance is determined by the pressure gradient and airflow rate
- the wider the tube, the greater the resistance to airflow
- resistance in the terminal bronchioles is lower than the primary bronchi
the wider the tube, the greater the resistance to airflow
What were the names of the 2 types of flow patterns of air through the respiratory tract? Where in the respiratory tract does each type of flow occur (upper or lower respiratory tract)?
- laminar (lower respiratory tract)
- turbulent (upper respiratory tract)
The respiratory tract can be divided functionally into 2 zones. The ___________ zone warms, humidifies, filters and carries the air to the terminal bronchioles.
conducting
Anaphylaxis is a life-threatening allergic reaction that results in symptoms such as an itchy rash, swelling of the eyes or tongue, and swelling of the respiratory bronchi. In regard to respiration, swelling of the bronchi causes obstruction of breathing due to constriction of the bronchial lumen. Based on what you know about surface area and resistance, what effect do you expect this to have on airflow resistance through the bronchi? Provide a brief description and why?
when the bronchi are constricted, the diameter of the tube will decrease and resistance will increase. This would decrease the amount of airflow through the bronchioles causing a difficulty to breath.
Label the layers of the pericardium and heart wall.
fibrous pericardium, parietal layer of pericardium, pericardial cavity, visceral layer of pericardium, myocardium, endocardium, heart chamber
Draw the path of blood as it flows through the heart starting from oxygenated blood entering the heart. Label the chambers and structures that blood passes through including the atria, ventricles, and valves.
You’ve got this!!
When you exercise, venous return of blood to your heart increases. Based on your knowledge of Starling’s law, what would happen to the amount of blood ejected from the left ventricle per contraction (stroke volume) during exercise? Explain.
Due to exercise, the venous blood is increased to the heart, the ventricle will stretch. This increases stroke volume, so more blood will be pushed out of the heart with an increased force of contraction.
Pilocarpine and atropine are two pharmacological drugs that are commonly used to alter heart rate. Pilocarpine is a muscarinic receptor agonist while atropine is a muscarinic receptor antagonist. Based on functions of these drugs how do you expect each of them to affect heart rate? Explain the mechanism of action of each drug.
- Atropine is an antagonist, it inhibits the activation of acetylcholine receptors. Atropine will increase the heart rate. If acetylcholine is added to the heart there should be no effect.
- Pilocarpine is and agonist, it activates the acetylcholine receptors and will decrease heart rate.
It is a hot, humid day. Mei is lying on her high school’s sports field looking at clouds. She stands up quickly and immediately feels lightheaded and starts to faint. Luckily, her classmates notice and gently lower her to the ground before she collapses. Explain why Mei felt lightheaded and faint upon standing? What are the ways our body normally compensates for this problem?
When Mei was sitting her blood was pooling in her lower extremities due to gravitational pull. When she stood up quickly, her heart rate increased but stroke volume was unable to increase. So, because there was a decreased amount of blood being pushed out of the heart, there was not enough blood going to the brain causing her to faint. To compensate for this problem, our vessels use vasoconstriction to facilitate the blood volume, use valves to prevent back flow, skeletal muscle helps to move the blood, breathing, and the ability to use pressure to move blood into the right atrium.
Describe the mechanistic differences between short-term blood pressure regulation and long-term blood pressure regulation.
- Short term blood pressure is a change for a short period of time. This uses neural communication of the baroreceptors. This can cause peripheral vasoconstriction or vasodilation and mobilization of blood reservoirs.
- Long term blood pressure changes the overall blood volume going to the heart. This can be regulated by the kidneys and change the overall hormones in the body to regulate blood pressure.
Name the major players in the renin-angiotensis-aldosterone system (RAAS)
- Renin
- Angiotensin
- Aldosterone
How does renin effect blood pressure and blood volume regulation
- Renin is secreted by juxtaglomerular cells in the kidneys in response to a decrease in blood pressure in the kidney arterioles, after sympathetic stimulation, and in response to prostaglandin E2 (PGE2) secretion by the adjacent macula densa cells. Renin is a protease that catalytically converts the peptide angiotensinogen in to angiotensin I. This will result in the generation of angiotensin II
- which ultimately will result in an increase in blood pressure and blood volume.
How does angiotensin effect blood pressure and blood volume regulation
- Angiotensinogen is a peptide produced by the liver. It circulates through the body and is enzymatically converted to angiotensin I by the enzyme renin in response to a decrease in MABP. Angiotensin I is further enzymatically converted into the effector peptide angiotensin II. Angiotensin II binds to angiotensin receptors on a variety of tissue that induces several responses. Binding to receptors in the vasculature results in vcasoconstriction and thus an increase in blood pressure. Binding of angiotensin II to receptors in the adrenal gland increases the release of the hormone aldosterone, which increases NaCl reabsorption from the kidneys, thus increasing blood pressure and blood volume.
- Lastly, binding of angiotensin II to receptors in the brain results in the secretion of the hormone antidiuretic hormone (ADH), which causes an increase in water reabsorption in the collecting ducts of the kidneys, thus increasing blood volume and blood pressure.
How does aldosterone effect blood pressure and blood volume regulation
- aldosterone is a steroid hormone secreted by the adrenal glands in response to a decrease in MABP. Secretion of aldosterone is induced by binding of the peptide angiotensin II to its receptors on the adrenal gland. Aldosterone acts at the level of the kidneys to increase the reabsorption of NaCl as well as the reabsorption of water back into the circulation.
- An increase in NaCl and water reabsorption leads to an increase in blood volume and ultimately an increase in blood pressure.
T or F: In respiratory physiology it is common to see turbulent flow in the upper respiratory tract and laminar flow in the lower respiratory tract
True
T or F: flow along a tube is driven by a difference in pressure
True
T or F: in general, an increase in cross sectional diameter of a tube will result in a greater resistance to airflow
False
T or F: the rate of flow along a tube is proportional to the pressure gradient
True
T or F: for any pressure gradient, more flow will occur when the flow is turbulent rather than laminar
False
Describe how the narrowing of Mila’s airways during an asthma attack affects resistance and airflow?
Resistance is a measure of the “difficulty” of flow. It results from friction between particles as they move in a gas, and from friction between the gas and the tube wall. It is affected by the dimensions of the airway (in this case, the radius of the airway). A decrease in cross-sectional diameter of the airway (i.e. narrowing of the airway) in asthma increases airway resistance, and decreases airflow through them. This is why Mila finds it hard to breathe during an asthma attack.
Mila uses an asthma inhaler to relax the smooth muscle that surrounds the airways. How might this allow her to breathe easy again?
In an asthma attack the airways may become narrowed due to contraction (spasms) of the smooth muscle that surrounds them. Therefore, an asthma inhaler that relaxes this smooth muscle will increase the radius of these airways. This will decrease resistance to airflow, allowing air to flow more freely, and allowing Mila to breathe easy again.
during a drop in blood pressure, prorenin changes into __________
renin
what is angiotensinogen? How does renin affect it?
- angiotensin is produced by the liver
- angiotensin is converted to angiotensin 1 by renin
what converts angiotensin 1 to angiotensin 2?
angeotensin converting enzyme (ACE)
what is angeotensin 2?
a hormone that binds to tissues for various effects
(increasing blood volume and blood pressure)
effects of angeotensin 2
- stimulates vasoconstriction in systemic arterioles
- promotes Na reabsorption in the kidneys
- induces release of aldosterone from the adrenal cortex
- stimulates the pituitary gland to release ADH
