Example exam Flashcards
What is the relevance of evaporative water cooling for human physiology? How does the mechanism work and under which conditins is it used?
When we need to cool down quickly such as under exercise and high temperatures. The mechanism is based on when we sweat the water will use our body heat to evaporate which lowers the bodies temperature.
Explain the mechanism of ventilation-perfusion matching in the lungs
There are local control mechanisms to match ventilation perfusion in the lungs. The capillary’s surrounding the alveoli’s can constrict or relax to provide blood to best ventilating alveoli’s. Also the bhroncioles, pulmonary arteries and systemic arteries can constrict and relax in response to pO2 and pCO2.
Explain the most important mechanism of carbon dioixde transport in the blood and how the mechanism regulated minute ventilation. Make use of the window to sketch any figoire or drawing that an support your explanation.
The most important transfer system is converting CO2 and H2O into bicarbonate, which is catalyzed by carbonic anhydrase which is found in red blood cells.
There are central and peripheral chemo receptors, central found in medulla and peripheral found in the aortic arch which sends pCO2 and pH and signal to the respiratory center which regulated minute ventilation aka increaisng or decreasing the breathing rate based on the amount of CO2 in the body.
What hemophilia? Describe its types, cause, symptoms and treatment.
Hemophilia is a rare genetic disorder that affects the body’s ability to clot blood properly. The disorder is caused by a deficiency in one of two clotting factors, factor VIII (hemophilia A) or factor IX (hemophilia B). Hemophilia is typically inherited from a person’s parents, and affects males more frequently than females, as it is an X-linked recessive disorder.
There are two main types of hemophilia:
Hemophilia A: Also known as classic hemophilia, this is the more common type and is caused by a deficiency of factor VIII.
Hemophilia B: Also known as Christmas disease, this is a less common type and is caused by a deficiency of factor IX.
The symptoms of hemophilia can range from mild to severe, depending on the level of clotting factor deficiency. People with hemophilia may experience frequent bruising, bleeding into joints and muscles, and prolonged bleeding after injury or surgery. In severe cases, spontaneous bleeding can occur, which can lead to serious complications such as organ damage, disability, and even death.
Treatment for hemophilia typically involves replacing the deficient clotting factor through regular infusions of clotting factor concentrate. In mild cases, this may only be necessary after an injury or surgery, while in more severe cases, regular infusions may be needed to prevent spontaneous bleeding. There are also medications available that can help increase clotting ability by promoting the production of clotting factors.
You are taking part of a student lab education, and get the task of developing a pharmacological drug that reduces the hart rate. briefly describe the mechanism of action of how you anticipate your drug to act to achieve such an effect. Motivate your choice by explaining what receptors and signaling pathways your drug would target.
Targeting the beta-1 adrenergic receptors in the heart, which are responsible for increasing heart rate and contractility.
One potential drug that could be used is a beta-blocker, which competitively inhibits the binding epinephrine and norepinephrine to the beta-1 adrenergic receptors. By blocking the actions of these neurotransmitters, the drug would reduce the activity of the sympathetic nervous system and decrease heart rate.
In terms of signaling pathways, beta-1 adrenergic receptors are coupled to G proteins, which the enzyme (cAMP). cAMP then activates protein kinase A (PKA), which phosphorylates several target proteins, leading to increased heart rate and contractility. A beta-blocker would inhibit this signaling pathway by preventing the activation of adenylate cyclase, thereby decreasing the production of cAMP and downstream signaling through PKA.
The renin angiotensin aldosterone system is initiated by secretin of renin from juxaglomerular cells in the kidneys. What effect does RAAS have on systemic blood pressure?
The RAAS is a complex hormonal system that is activated when blood pressure drops, causing the kidneys to release the enzyme renin.
Renin acts on a protein called angiotensinogen, which is produced by the liver, to produce angiotensin I. Angiotensin I is then converted into angiotensin II by an enzyme called angiotensin-converting enzyme (ACE), which is primarily found in the lungs.
Angiotensin II is a potent vasoconstrictor, meaning that it causes the blood vessels to narrow, which increases blood pressure. It also stimulates the release of aldosterone from the adrenal glands, which causes the kidneys to retain sodium and water, leading to an increase in blood volume and further increasing blood pressure.
Through what mechanism does RAAS affect systemic blood pressure?
The Renin-Angiotensin-Aldosterone System (RAAS) affects systemic blood pressure through a combination of vasoconstriction and sodium/water retention.
When blood pressure drops, the kidneys release the enzyme renin, which then acts on a protein called angiotensinogen to produce angiotensin I. Angiotensin I is then converted into angiotensin II by the enzyme angiotensin-converting enzyme (ACE), primarily found in the lungs.
Angiotensin II is a potent vasoconstrictor, meaning that it causes the blood vessels to narrow, leading to an increase in blood pressure. It also stimulates the release of aldosterone from the adrenal glands, which causes the kidneys to retain sodium and water, leading to an increase in blood volume and further increasing blood pressure.
What stimuli induce secretion of renin by juxtaglomerular cells?
Juxtaglomerular cells are specialized cells located in the walls of the afferent arterioles that supply blood to the glomeruli in the kidneys. These cells are responsible for producing and secreting the enzyme renin in response to certain stimuli.
The secretion of renin by juxtaglomerular cells is stimulated by several factors, including:
Decreased blood pressure or blood volume: When blood pressure or blood volume decreases, it triggers a reflex response that activates the juxtaglomerular cells to secrete renin.
Sympathetic nervous system activation: The sympathetic nervous system, which is responsible for the body’s “fight or flight” response, can also stimulate the release of renin from the juxtaglomerular cells.
Decreased sodium chloride concentration in the distal tubule: Juxtaglomerular cells are sensitive to the concentration of sodium chloride in the distal tubule of the kidney. If the concentration of sodium chloride is too low, it can trigger the release of renin.
Prostaglandins: Certain prostaglandins, which are hormones produced in response to inflammation and injury, can also stimulate the release of renin.
Overall, the secretion of renin by juxtaglomerular cells is a complex process that is regulated by multiple factors in response to changes in the body’s needs.
Statement 1. Glycogen stored in skeletal muscle and liver can be used as a source of glucose
Statement 2. Most tissues with the exception of the brain can use fatty acids as energy source
Statement 3. Production of glucose from aminoacids is called gluconeogenesis
Statement 4. Reduced insulin levels lead to glycogenolysis
Statement 5. Increased glucagon levels trigger lipolysis.
A) Only 1 and 3 is TRUE
B) Only 2 and 5 are TRUE
C) Only 1, 3 and 5 are TRUE
D) Only 2, 4 and 5 are TRUE
E) All statements are TRUE
The correct answer is:
E
Explanation:
Statement 1 is TRUE. Both skeletal muscle and liver store glycogen, which can be broken down into glucose and used as an energy source when needed.
Statement 2 is TRUE
Statement 3 is TRUE. Gluconeogenesis is the process by which the body produces glucose from non-carbohydrate sources, such as amino acids.
Statement 4 is TRUE
Statement 5 is TRUE. Glucagon is a hormone that promotes the breakdown of glycogen and the release of glucose into the bloodstream, as well as the breakdown of fat (lipolysis) to provide an alternative source of energy.
C is correct
Definition 1. Heat convection is the heat transfer between adjacent molecules
Definition 2. Shivering thermogenesis results from the production of heat by muscles not producing
external work
Definition 3. Skin vasoconstriction leads to increased conductance and increased heat loss
Definition 4. Within the thermoneutral zone body temperature is exclusively regulated by changes
in skin conductance
Definition 5. The temperature control of the body is located in the hypothalamus
A) Only 1 and 3 are TRUE
B) Only 2 and 4 are TRUE
C) Only 4 and 5 are TRUE
D) Only 2, 4 and 5 are TRUE
E) Only 3, 4 and 5 are TRUE
The correct answer is:
C) Only 4 and 5 is true
Explanation:
Statement 1 is FALSE. Heat convection is the transfer of heat through the movement of fluid or air currents.
Statement 2 is FALSE. Shivering thermogenesis results from the production of heat by muscles that are contracting involuntarily to generate heat.
Statement 3 is FALSE. Vasoconstriction is the narrowing of blood vessels, which reduces blood flow and decreases the exchange of heat between the body and the environment.
Statement 4 is TRUE. Within the thermoneutral zone, body temperature is maintained within a narrow range by adjustments in skin conductance and sweating, without the need for significant thermoregulatory responses such as shivering or sweating.
Statement 5 is TRUE. The hypothalamus, specifically the preoptic area, plays a central role in the regulation of body temperature by integrating signals from thermoreceptors in the skin and core body temperature sensors, and initiating appropriate physiological responses to maintain body temperature within a narrow range.
Statement 1. Gas volume and pressure are directly proportional
Statement 2. In a mixture of gases like air, the total pressure is the sum of the partial pressures of
the gases in the mixture
Statement 3. The volume of gas that will dissolve in a solvent is proportional to the solubility of the
gas and the gas pressure
Statement 4. The partial pressure of nitrogen at sea level is approximately 0.8 atm
Statement 5. The partial pressure of a gas is inversely related to its concentration
F) Only 3 is TRUE
G) Only 1 and 3 are TRUE
H) Only 4 and 5 are TRUE
I) Only 2, 4 and 5 are TRUE
J) Only 3, 4 and 5 are TRUE
The correct answer is:
I) Only 2, 4 and 5 are TRUE
Explanation:
Statement 1 is FALSE, they are inversely proportional
Statement 2 is TRUE.
Statement 3 is FALSE
Statement 4 is TRUE. The partial pressure of nitrogen at sea level is approximately 0.8 atm.
Statement 5 is TRUE. This is known as the relationship between partial pressure and concentration, which states that the partial pressure of a gas in a mixture is proportional to its concentration in the mixture.
Which of the following situations would trigger a hyperventilatory response (increased pulmonary
ventilation) in a healthy individual?
Situation 1. Blood alkalosis (increased carbon dioxide levels in the blood)
Situation 2. Increased blood pCO2
Situation 3. Hypoxemia (lowered blood pO2)
Situation 4. Decreased blood bicarbonate levels (HCO3
-)
A) Only 1 and 2
B) Only 2 and 3
C) Only 1, 2 and 3
D) Only 1, 3 and 4
E) All of the above
C) 1,2,3
Which of the following statement/s in relation to oxygen transport and hemoglobin is/are TRUE?
Statement 1. Reduced blood pH reduces the total amount of oxygen bound to hemoglobin at high partial pressures (pO2 > 200 mmHg)
Statement 2. Anemia reduces oxygen transport by shifting the oxygen dissociation curve to the
right
Statement 3. Monoxide outcompetes oxygen
Statement 4. Increased concentrations of 2,3-DPG decrease the oxygen transport capacity of the
blood
Statement 5. Hemoglobin oxygen saturation is always highest in pulmonary arteries
A) Only 3 is TRUE
B) Only 1 and 3 are TRUE
C) Only 4 and 5 are TRUE
D) Only 1, 2 and 4 are TRUE
E) Only 3, 4 and 5 are TRUE
3 is true 4 is true
Look at exam paper qustion 6
The oxygen dissociation curve shown below shows the oxygen binding properties of maternal and
fetal hemoglobin. Evaluate the following statements in relation to the graph and determine which
of them are TRUE
Statement 1. The A curve represents that of fetal hemoglobin because the fetus needs a higher
affinity to obtain oxygen from the maternal hemoglobin
Statement 2. The B curve represents that of maternal hemoglobin because the maternal blood has
a lower P50 value
Statement 3. In the curves above a placental partial pressure of oxygen of 40 mmHg would result
in a transfer of oxygen from hemoglobin A to hemoglobin B because hemoglobin A is
more saturated with oxygen
Statement 4. In the curves above a placental partial pressure of oxygen of 40 mmHg would result
in a transfer of oxygen from hemoglobin B to hemoglobin A because hemoglobin B
has a lower affinity
A) Only 1 and 2 are TRUE
B) Only 1 and 3 are TRUE
C) Only 1 and 4 are TRUE
D) Only 2 and 3 are TRUE
E) Only 2 and 4 are TRUE
Question 7
Which one of the following is NOT regarded as part of primary hemostasis?
A) Vasoconstriction
B) Platelet recruitment
C) Granule secretion
D) Von Willebrand factor signaling
E) Fibrinolysis
E) Fibrinolysis is not regarded as part of primary hemostasis. It is a separate process that occurs during secondary hemostasis to dissolve fibrin clots once tissue repair is completed. Primary hemostasis involves vasoconstriction, platelet recruitment, granule secretion, and von Willebrand factor signaling.
