1.
Myasthenia Gravis:
Correct Answer
B. Is an autoimmune disorder of neuromuscular transmission
Explanation
Myasthenia Gravis is an autoimmune disorder of neuromuscular transmission. This means that the immune system mistakenly attacks the neuromuscular junction, where the nerve signals are transmitted to the muscles. This attack leads to muscle weakness and fatigue, as the communication between the nerves and muscles is disrupted. It is not a genetic disorder or a disorder of motor neurons. Additionally, it is not a degenerative disorder resulting in the death of dopamine generating cells, which is characteristic of Parkinson's disease.
2.
Where can the strongest heart sounds usually be found?
Correct Answer
D. To the left of the sternum
Explanation
The correct answer is "To the left of the sternum." The strongest heart sounds are usually heard to the left of the sternum, specifically at the apex of the heart. This is because the apex is the point of maximal impulse and is closest to the chest wall. The left ventricle, which is responsible for generating the strongest heart sounds, is located at the apex of the heart.
3.
Which type of receptor would be involved in extreme heat?
Correct Answer
D. Noiceiceptor
4.
____________ can easily be tested for by a treadmill stress test. (Hint: PMHR=220-yoa)
Correct Answer
C. ChronotropHic Incompetence
Explanation
Chronotrophic incompetence refers to the inability of the heart to increase its rate appropriately during physical activity. This can be tested for by a treadmill stress test, where the individual is asked to walk or run on a treadmill while their heart rate is monitored. If the heart rate does not increase adequately in response to the exercise, it suggests chronotrophic incompetence. This condition may be caused by various factors, such as medication side effects or damage to the heart's electrical system.
5.
Which heart condition involves huge ventricular volumes from the enlargement of the ventricular cavity (hypertrophy)?
Correct Answer
A. Chronic aortic regurgitation
Explanation
Chronic aortic regurgitation involves the backflow of blood from the aorta into the left ventricle during diastole, leading to an increase in ventricular volume. This condition causes the ventricular cavity to enlarge, resulting in hypertrophy.
6.
Which type(s) of hearing loss are by far more common?
Correct Answer
C. Conductive & Sensorineural
Explanation
Conductive and sensorineural hearing loss are by far more common compared to central hearing loss. Conductive hearing loss occurs when there is a problem with the outer or middle ear, such as a blockage or damage to the eardrum or the tiny bones in the middle ear. Sensorineural hearing loss, on the other hand, is caused by damage to the inner ear or the auditory nerve. Central hearing loss, which involves problems with the brain's ability to process sound, is relatively less common. Therefore, the correct answer is conductive and sensorineural hearing loss.
7.
Looking at an ECG, which interval would measure the conduction time of the AV node and His bundle?
Correct Answer
B. PR interval
Explanation
The PR interval on an ECG measures the conduction time of the AV node and His bundle. This interval represents the time it takes for the electrical signal to travel from the atria to the ventricles. It begins at the start of the P wave, which represents atrial depolarization, and ends at the start of the QRS complex, which represents ventricular depolarization. Therefore, the PR interval is the correct answer as it specifically measures the conduction time of the AV node and His bundle.
8.
Which component of the nervous system of the lung is involved in inhibitory events (bronchodilation)?
Correct Answer
A. NANC System
Explanation
The NANC system, or the nonadrenergic, noncholinergic system, is involved in inhibitory events such as bronchodilation in the lung. This system consists of nerve fibers that release neurotransmitters other than adrenaline or acetylcholine, which can cause relaxation of the smooth muscles in the airways, leading to bronchodilation.
9.
Regarding the ventricular action potential phases, which phase is characterized by a plateau and balance b/t inward movement of Ca2+ and outward movement of K+?
Correct Answer
B. pHase 2
Explanation
Phase 2 of the ventricular action potential is characterized by a plateau and a balance between the inward movement of Ca2+ and the outward movement of K+. During this phase, the voltage-gated Ca2+ channels open, allowing Ca2+ to enter the cell. At the same time, the delayed rectifier potassium channels open, allowing K+ to leave the cell. The balance between these two ions results in a prolonged depolarization, creating the plateau phase. This plateau phase helps to sustain the contraction of the ventricles and ensures proper pumping of blood.
10.
A decrease in pulmonary compliance (change in volume/change in pressure) could be associated with?
Correct Answer
D. Fibrosis of lung tissue
Explanation
A decrease in pulmonary compliance, which refers to the ease with which the lungs can expand, can be associated with fibrosis of lung tissue. Fibrosis is the formation of excess fibrous connective tissue in the lungs, which can lead to stiffening and decreased elasticity of the lung tissue. This stiffness makes it harder for the lungs to expand and results in a decrease in pulmonary compliance.
11.
Which type of heart disease has a hallmark of a fatty streak made up of LDL cholesterol & macrophages (yellow in color) in vessel walls?
Correct Answer
C. Atherosclerosis
Explanation
Atherosclerosis is the correct answer because it is a type of heart disease characterized by the buildup of a fatty streak, consisting of LDL cholesterol and macrophages, in the walls of blood vessels. This buildup can lead to the narrowing and hardening of the arteries, restricting blood flow and potentially causing various cardiovascular complications. CHF, pericarditis (coxsackievirus), and Prinzmetal angina are not specifically associated with the hallmark of a fatty streak in vessel walls.
12.
A patient presents with an embolic stroke. Which type of heart condition should be in the differential (since embolic stroke may be a first feature)?
Correct Answer
A. Nonbacterial thrombotic endocarditis
Explanation
Nonbacterial thrombotic endocarditis is a condition characterized by the formation of non-infectious thrombi on the cardiac valves. These thrombi can break off and travel to other parts of the body, leading to embolic strokes. Since embolic stroke may be the first feature of this condition, it should be considered in the differential diagnosis when a patient presents with an embolic stroke. Infective endocarditis, rheumatic heart disease, and subendocardial MI may also cause embolic strokes, but nonbacterial thrombotic endocarditis is specifically mentioned as a possible cause in this scenario.
13.
Lacrimation is part of:
Correct Answer
B. The autonomic nervous system, specifically parasympathetic
Explanation
Lacrimation refers to the production of tears. Tears are produced by the lacrimal glands, which are controlled by the autonomic nervous system. The autonomic nervous system is responsible for regulating involuntary bodily functions, such as heart rate, digestion, and tear production. The parasympathetic division of the autonomic nervous system is specifically responsible for rest and digest activities, including tear production. Therefore, lacrimation is part of the autonomic nervous system, specifically the parasympathetic division.
14.
The histopathology of which pulmonary disease involves thickened airway mucosa with inflammatory cells?
Correct Answer
C. Asthma
Explanation
Asthma is a pulmonary disease characterized by inflammation and narrowing of the airways. The histopathology of asthma shows thickened airway mucosa, which is caused by the accumulation of inflammatory cells such as eosinophils, lymphocytes, and mast cells. This inflammation leads to increased mucus production and bronchoconstriction, resulting in symptoms like wheezing, shortness of breath, and coughing. Emphysema is characterized by destruction of the alveoli, bronchitis involves inflammation of the bronchial tubes, and pulmonary fibrosis involves scarring of the lung tissue. None of these conditions exhibit the specific histopathological findings of thickened airway mucosa with inflammatory cells seen in asthma.
15.
What type of capillary (the smallest of the body's blood vessels) has pores in endothelial cells covered by the diaphragm & allows for proteins to diffuse?
Correct Answer
D. Fenestrated
Explanation
Fenestrated capillaries are the type of capillaries that have pores in the endothelial cells covered by the diaphragm, allowing for proteins to diffuse. These capillaries are found in organs that require rapid exchange of large molecules, such as the kidneys and intestines. The pores in the endothelial cells allow for the movement of proteins and other large molecules across the capillary wall. This type of capillary is specialized for filtration and absorption processes.