BLOCK 3 FINALS REVIEW Flashcards
(357 cards)
1
Q
A 75-year-old man quickly stands from a seated position and becomes dizzy. Which reflex is responsible for adjusting his blood pressure to prevent syncope? The baroreceptor reflex
A
a negative feedback system mediated by mechanoreceptors in the carotid sinus and aortic arch
2
Q
A 68-year-old man presents with left ventricular failure. What cardiac structure
A
composed of irregular muscular ridges
3
Q
A surgeon notes a groove separating the atria and ventricles during cardiac surgery. What is this landmark? The coronary sulcus
A
also called the atrioventricular groove
4
Q
A patient has an MI affecting the posterior interventricular artery. Which vein is likely to be found running alongside it?
A
The middle cardiac vein runs in the posterior interventricular sulcus with the posterior descending artery.
5
Q
A patient’s angiogram shows the posterior descending artery arises from the right coronary artery. What is the patient’s heart dominance? This is right-dominant circulation
A
the most common type (~85%)
6
Q
During bypass surgery
A
a branch of the RCA supplying the inferior wall of the right ventricle is grafted. Which artery is this? The right marginal artery
7
Q
A catheter enters the right atrium and identifies a large venous opening near the tricuspid valve. What is this structure?
A
The coronary sinus opening where venous blood from the myocardium enters the right atrium.
8
Q
A transverse CT shows a flat posterior heart surface adjacent to the esophagus. What part of the heart is this? The base of the heart
A
mostly the left atrium
9
Q
An EKG shows ST elevation in leads II
A
III
10
Q
A patient with a recent inferior MI develops severe mitral regurgitation. Which structure was likely damaged? The posteromedial papillary muscle
A
which has a single blood supply (RCA)
11
Q
Why doesn’t the heart over-expand during high volume states? The fibrous pericardium limits overdistension of the heart
A
providing structural support.
12
Q
A patient with pericarditis experiences referred pain to the shoulder. Which nerve is responsible? The phrenic nerve (C3–C5) innervates the fibrous pericardium and refers pain to the shoulder/neck.
A
13
Q
A newborn has a patent foramen ovale. In a healthy adult
A
what structure does this correspond to? The fossa ovalis
14
Q
A blockage in the SA nodal branch of the RCA affects what part of the heart’s conduction? It impairs the sinoatrial (SA) node
A
the primary pacemaker coordinating atrial contraction.
15
Q
What is the key anatomical difference between the tricuspid and semilunar valves? The tricuspid valve has chordae tendineae attached to papillary muscles
A
unlike semilunar valves.
16
Q
An EKG shows ST elevation in leads II, III, and aVF. Which coronary artery is likely occluded?
A
These inferior leads correspond to the right coronary artery in a right-dominant system.
17
Q
A patient with a recent inferior MI develops severe mitral regurgitation. Which structure was likely damaged?
A
The posteromedial papillary muscle, which has a single blood supply (RCA), is vulnerable in inferior MIs.
18
Q
Why doesn’t the heart over-expand during high volume states?
A
The fibrous pericardium limits overdistension of the heart, providing structural support.
19
Q
A patient with pericarditis experiences referred pain to the shoulder. Which nerve is responsible?
A
The phrenic nerve (C3–C5) innervates the fibrous pericardium and refers pain to the shoulder/neck.
20
Q
A newborn has a patent foramen ovale. In a healthy adult, what structure does this correspond to?
A
The fossa ovalis, a depression in the interatrial septum, is a remnant of the fetal foramen ovale.
21
Q
A blockage in the SA nodal branch of the RCA affects what part of the heart’s conduction?
A
It impairs the sinoatrial (SA) node, the primary pacemaker coordinating atrial contraction.
22
Q
What is the key anatomical difference between the tricuspid and semilunar valves?
A
The tricuspid valve has chordae tendineae attached to papillary muscles, unlike semilunar valves.
23
Q
A 45-year-old woman presents with dizziness and bradycardia. The EKG shows an absence of P waves. What part of the conduction system might be compromised?
A
The sinoatrial (SA) node, which initiates the electrical impulse for atrial contraction, may be dysfunctional.
24
Q
A 60-year-old man experiences wide QRS complexes and poor ventricular coordination after an MI. Which fibers are likely impaired?
A
Purkinje fibers, which conduct impulses rapidly through the ventricles for synchronized contraction.
25
A trauma patient has cardiac arrhythmias and hypotension. Which autonomic structure innervates the heart and may be involved?
The cardiac plexus, a network of sympathetic and parasympathetic fibers that regulate heart rate and contraction.
26
In which layer of the heart do most cardiac myocytes reside and generate contractile force?
The myocardium is the thick muscular middle layer of the heart responsible for contraction.
27
An echocardiogram shows abnormal motion of the interventricular septum. What cardiac structure does this refer to?
The septum is the wall separating the right and left chambers of the heart, including the interatrial and interventricular septa.
28
A 50-year-old patient has a heart block due to ischemia in the area of the SA nodal branch. Which coronary artery is likely involved?
The right coronary artery, which gives rise to the SA nodal branch in most people.
29
A cardiac surgeon notes connective tissue surrounding the heart. What is the name and function of this structure?
The fibrous pericardium surrounds the heart, preventing overdistention and anchoring it to surrounding structures.
30
A trauma patient has pericardial effusion and experiences shoulder pain. What nerve is responsible for the pain?
The phrenic nerve (C3–C5), which innervates the fibrous pericardium and refers pain to the shoulder.
31
A newborn with cyanosis has an echocardiogram showing a persistent opening between the atria. What is the embryologic origin of this defect?
The foramen ovale, which should close after birth to form the fossa ovalis, is a fetal circulatory bypass.
32
An anatomy lab dissection reveals thin strands attaching atrioventricular valve leaflets to papillary muscles. What are these structures?
The chordae tendineae, which prevent valve prolapse during ventricular contraction and are absent in semilunar valves.
33
What is the likely underlying cardiac condition in a patient with peripheral edema, hepatomegaly, and jugular venous distention?
Decompensated right-sided heart failure, which causes systemic venous congestion.
34
What does a prolonged PR interval on an EKG indicate about cardiac conduction?
A prolonged PR interval suggests delayed conduction through the AV node (first-degree heart block).
35
What structure initiates depolarization of the heart and sets the pace of the cardiac cycle?
The SA node is the heart’s natural pacemaker, initiating depolarization and atrial contraction.
36
Why does the AV node delay conduction during the cardiac cycle?
The AV node delays conduction to allow complete ventricular filling before contraction.
37
What is the physiologic goal of administering vasopressors to a hypotensive male?
To increase mean arterial pressure (MAP) by vasoconstriction and improved perfusion.
38
Which ion channel is responsible for the slow depolarization leading to cardiac muscle contraction?
Calcium channels (L-type) are slow channels responsible for the plateau phase and trigger contraction.
39
What reflex is failing to respond quickly enough in a 70-year-old man who gets dizzy when standing?
The baroreceptor reflex is failing to compensate for the drop in blood pressure (orthostatic hypotension).
40
Which ion is most responsible for returning the membrane to resting potential during repolarization of cardiac muscle?
Potassium (K+) efflux is responsible for repolarization in cardiac cells.
41
How does extracellular calcium enhance cardiac contractility?
Extracellular calcium increases calcium-induced calcium release, acting as a positive inotrope.
42
Which three factors determine stroke volume?
Preload (venous return), afterload (resistance), and contractility (inotropy).
43
Which brain region primarily regulates blood pressure and heart rate?
The medulla oblongata controls autonomic regulation of mean arterial pressure.
44
What is the mechanism in a patient with septic shock who has warm extremities and hypotension?
Vasodilatory shock due to systemic inflammatory mediators causing loss of vascular tone.
45
What is the likely diagnosis for a 50-year-old woman with refractory hypertension and a bruit over her flank?
Renal artery stenosis, a common cause of secondary hypertension.
46
Which cranial nerve carries parasympathetic innervation to slow heart rate?
The vagus nerve (CN X) provides parasympathetic input to the SA and AV nodes.
47
Why does a patient with supraventricular tachycardia (SVT) develop hypotension and dizziness?
High heart rate reduces ventricular filling time, lowering cardiac output.
48
Which valve connects the right atrium and right ventricle?
The tricuspid valve regulates blood flow between the right atrium and ventricle.
49
What phase of the cardiac cycle occurs when all valves are closed and pressure builds in the ventricles?
Isovolumetric contraction, which precedes ventricular ejection.
50
Which hormone is released in response to atrial stretch and lowers blood pressure?
Atrial natriuretic peptide (ANP), which promotes natriuresis and vasodilation.
51
Why is the myocardium of the left ventricle thicker than the right?
It must generate more pressure to overcome systemic vascular resistance.
52
Why does blood pressure often rise in elderly patients?
Reduced vascular compliance increases systolic pressure with aging.
53
What system is affected in a patient with kidney failure who has low plasma renin levels?
The RAAS system; reduced renin impairs aldosterone-mediated blood pressure regulation.
54
Why are IV fluids administered in hypotensive patients?
To increase intravascular volume, thereby raising preload and cardiac output.
55
What valvular abnormality might be present in a patient with pulmonary edema and dyspnea?
Mitral valve stenosis, which impedes left atrial emptying and raises pulmonary pressure.
56
Which arterial category do the gonadal arteries fall under?
Gonadal arteries are paired visceral branches of the abdominal aorta.
57
What artery supplies the lateral left ventricle?
The circumflex artery, a branch of the left coronary artery, supplies the lateral left ventricle.
58
Which artery is affected in a popliteal aneurysm behind the knee?
The popliteal artery, a continuation of the femoral artery behind the knee.
59
What is the significance of the left subclavian artery arising directly from the aorta?
The left subclavian artery branches directly from the aortic arch, unlike the right side.
60
Which artery provides the majority of blood supply to the diaphragm?
The inferior phrenic arteries, branches of the abdominal aorta, supply most of the diaphragm.
61
What vein drains the face, scalp, occipital region, and posterior auricular areas?
The external jugular vein, which is formed by branches of the external carotid system.
62
Which artery contributes to the basilar artery and the posterior circle of Willis?
The vertebral arteries merge to form the basilar artery, which supplies the posterior cerebral circulation.
63
Where do you palpate the dorsalis pedis artery?
On the dorsum of the foot, lateral to the extensor hallucis longus tendon.
64
Which artery is commonly palpated postoperatively to assess perfusion to the foot?
The posterior tibial artery, located behind the medial malleolus.
65
Where is a common superficial venous site for drawing blood on the back of the hand?
The dorsal venous network of the hand.
66
What is the most common venipuncture site in the cubital fossa?
The median cubital vein, located in the antecubital space.
67
Which artery is most commonly used for arterial blood gas sampling?
The radial artery, due to its superficial location and collateral circulation.
68
Which vein is often harvested for coronary artery bypass grafting?
The great saphenous vein, which runs along the medial aspect of the leg.
69
Which anatomical landmarks are relevant for a femoral artery puncture site infection?
The femoral artery lies just inferior to the inguinal ligament in the femoral triangle.
70
What major artery does the vertebral artery branch from?
The vertebral artery branches off the subclavian artery.
71
Which three arteries branch from the celiac trunk to supply foregut organs?
The common hepatic, splenic, and left gastric arteries.
72
Which artery is likely injured if a man loses consciousness after being struck in the temple?
The superficial temporal artery, a branch of the external carotid.
73
What artery is likely damaged in an epidural hematoma and where does it originate?
The middle meningeal artery, a branch of the maxillary artery from the external carotid.
74
What makes venous sinuses unique compared to peripheral veins?
They are endothelial-lined channels in the dura mater without valves.
75
Which artery supplies most of the pelvic organs?
The internal iliac artery, a major branch of the common iliac artery.
76
What vein drains nutrient-rich blood from abdominal organs to the liver for filtration?
The hepatic portal vein.
77
Which artery runs in the region of swelling near the axilla after lymph node dissection?
The lateral thoracic artery, which runs along the lateral border of the pectoralis minor.
78
A mid-shaft humeral fracture risks injury to which artery?
The deep brachial artery (profunda brachii), which runs in the radial groove.
79
Which artery is best for palpating pulses in children during emergency assessment?
The brachial artery, located in the medial aspect of the upper arm.
80
What is the likely vascular cause of severe postprandial abdominal pain and weight loss?
Chronic mesenteric ischemia due to stenosis of the superior mesenteric artery (SMA).
81
A patient with liver disease presents with peripheral edema. What plasma protein is most likely decreased?
Albumin, which maintains oncotic pressure and is synthesized in the liver.
82
What immune reaction occurs when mismatched blood types are mixed during transfusion?
Agglutination, where antibodies bind to incompatible antigens, leading to clumping and hemolysis.
83
Which blood type is considered the universal donor for red blood cells?
O negative, because it lacks A, B, and Rh antigens.
84
Which blood type is most common and can donate to any Rh-positive individual?
O positive, as it has no A/B antigens but carries Rh factor.
85
A jaundiced infant has elevated levels of a yellow pigment. What is it?
Bilirubin, a breakdown product of heme, which accumulates in liver dysfunction.
86
Which arterial structure connects the vertebrobasilar system and internal carotids in the brain?
The Circle of Willis, a vascular ring that provides collateral circulation to the brain.
87
A patient with asthma is treated with albuterol. Which white blood cell type might be elevated due to inflammation?
Basophils, which are involved in allergic responses and may contribute to asthma.
88
Which white blood cell is the most abundant and plays a key role in respiratory burst?
Neutrophils, the first responders that kill pathogens via oxidative burst.
89
A patient with parasitic worm infection shows elevated eosinophils. Why?
Eosinophils combat multicellular parasites and mediate allergic responses.
90
Which agranulocyte is the second most abundant white blood cell type?
Lymphocytes, which include B and T cells and play a central role in adaptive immunity.
91
Which cell is similar to basophils and releases histamine in allergic reactions?
Mast cells, tissue-resident cells that release histamine like basophils.
92
Which granulocyte produces heparin and histamine, contributing to inflammation?
Basophils, which are involved in allergic responses and anticoagulation.
93
Which clotting-related protein binds platelets to exposed collagen?
Von Willebrand factor, which mediates platelet adhesion in damaged vessels.
94
A dialysis patient has thrombocytopenia. Which hormone is likely deficient due to kidney failure?
Thrombopoietin, which is produced in the liver and kidneys to regulate platelet production.
95
Which hormone stimulates red blood cell production in response to hypoxia?
Erythropoietin, primarily released by the kidneys.
96
Which group of signaling molecules drives the differentiation of blood cell lineages?
Colony-stimulating factors (CSFs), which promote hematopoiesis.
97
A physician orders a reticulocyte count. What is being assessed?
Reticulocyte levels reflect the rate of red blood cell production.
98
Which clotting factor starts the extrinsic coagulation pathway?
Factor VII, which is activated by tissue factor in the extrinsic pathway.
99
Which molecule is released by activated platelets to enhance aggregation?
Thromboxane A2, a potent vasoconstrictor and platelet activator.
100
What do calcium, factor X, and tissue factor (factor III) collectively form?
Together they help activate prothrombin to thrombin; thrombin then activates factor XIII.
101
Why is free iron toxic in the bloodstream, and how is it safely stored?
Free iron generates free radicals; it is stored as ferritin in cells.
102
Why are packed red blood cells used in transfusion for anemia?
They increase oxygen-carrying capacity immediately due to higher hemoglobin content.
103
Which molecule produced by endothelial cells helps suppress platelet activation?
Nitric oxide, which maintains vascular homeostasis and inhibits platelet aggregation.
104
What enzyme converts fibrinogen to fibrin during coagulation?
Thrombin, a key protease in the coagulation cascade.
105
Which growth factor promotes new blood vessel formation and is targeted in cancer therapy?
Vascular endothelial growth factor (VEGF), which stimulates angiogenesis.
106
What anatomical feature helps differentiate the jejunum from the ileum?
The jejunum has longer vasa recta and fewer arterial arcades compared to the ileum.
107
In a patient with portal hypertension, where might varices form due to portacaval anastomoses?
At sites like the esophagus, rectum, and umbilicus where portal and systemic venous systems overlap.
108
What dermatomes cover the skin from the umbilicus to the suprapubic region?
T10–T12 dermatomes supply this area.
109
A patient with atrial fibrillation presents with abdominal pain and ischemia of the cecum. What vessel is likely involved?
The superior mesenteric artery (SMA), which supplies the midgut, including the cecum.
110
A patient has left lower quadrant pain, fever, and leukocytosis. What is the likely diagnosis?
Diverticulitis, most commonly affecting the sigmoid colon.
111
Where is the duodenum located anatomically?
It is the first part of the small intestine, curving around the head of the pancreas.
112
What duct carries pancreatic enzymes into the duodenum?
The main pancreatic duct (of Wirsung), which merges with the bile duct at the hepatopancreatic ampulla.
113
A patient with chronic GERD develops dysphagia and weight loss. What type of cancer is suspected?
Adenocarcinoma at the gastroesophageal (GE) junction.
114
Why is the duodenum the most common site for peptic ulcers?
It receives acidic chyme directly from the stomach, making it vulnerable to damage.
115
Which nerves mediate sympathetic innervation to the abdominal organs via the celiac plexus?
Thoracic splanchnic nerves (greater, lesser, least) synapse in the celiac plexus.
116
What is notable about the left renal vein anatomically?
It crosses the midline anterior to the aorta and drains the left kidney, adrenal gland, and gonad.
117
What is the function of the ileocecal valve?
It prevents backflow of contents from the cecum into the small intestine.
118
What structure must be identified and clipped during gallbladder removal?
The cystic duct, which connects the gallbladder to the common bile duct.
119
Which artery must be ligated during a cholecystectomy to prevent bleeding?
The cystic artery, typically a branch of the right hepatic artery.
120
Which artery supplies the superior, superficial surface of the diaphragm?
The musculophrenic artery, a branch of the internal thoracic artery.
121
What artery supplies the lower abdominal wall below the umbilicus and above the inguinal ligament?
The inferior epigastric artery.
122
What is the main function of the spleen?
It filters blood and recycles old red blood cells.
123
A patient with painful rectal bleeding has hemorrhoids located where?
Below the pectinate (dentate) line—these are external hemorrhoids and are painful.
124
Which arteries supply the stomach, and what is their origin?
Short gastric, gastric, and gastro-omental arteries, all branches of the celiac trunk.
125
Fluid accumulating behind the stomach and lesser omentum enters what space?
The lesser sac (omental bursa).
126
What are the two ligaments that make up the lesser omentum?
The hepatoduodenal and hepatogastric ligaments.
127
Is the jejunum considered intraperitoneal or retroperitoneal?
Intraperitoneal—it is suspended by mesentery.
128
Periumbilical lymph drains to which lymph node groups?
Either axillary or superficial inguinal nodes.
129
What is the first layer of the anterior abdominal wall beneath the skin?
Camper’s fascia, a superficial fatty layer.
130
What is absent below the arcuate line of the abdominal wall?
The posterior rectus sheath.
131
How does the stomach increase surface area for digestion?
Rugae—gastric folds that allow expansion and increased SA.
132
What is the double layer of peritoneum that suspends organs called?
A mesentery—it anchors intraperitoneal organs to the posterior wall.
133
What are the spaces between the colon and abdominal wall called?
Paracolic gutters, which allow fluid movement in the peritoneal cavity.
134
Which structure controls bile and pancreatic juice flow into the duodenum?
The sphincter of Oddi.
135
What structure regulates gastric emptying into the duodenum?
The pyloric sphincter.
136
A patient with chronic alcoholism has elevated liver enzymes. Which enzyme is particularly increased?
Gamma-glutamyl transferase (GGT), often elevated in alcohol-related liver disease.
137
Why is rice considered an incomplete protein?
It lacks some essential amino acids, particularly lysine.
138
Which vitamin is essential for proper nerve function and is deficient in chronic alcohol use?
Thiamine (vitamin B1), crucial for neural health.
139
Why might a provider recommend vitamin E to a patient?
Vitamin E functions as an antioxidant, protecting cells from oxidative damage.
140
What is one dietary recommendation for obese patients to aid in weight loss?
Reduce intake of simple carbohydrates to lower insulin spikes and caloric intake.
141
A patient presents with vesicular lesions along the hard palate midline. What structure are they aligned with?
The palatine raphe, a ridge on the roof of the mouth.
142
Which hormone stimulates gallbladder contraction in response to fat in the duodenum?
Cholecystokinin (CCK).
143
What is the innermost layer of the esophageal wall?
The mucosa, which comes in direct contact with ingested material.
144
What is the coordinated muscular activity that propels food through the digestive tract?
Peristalsis, involving smooth muscle contractions.
145
Which neural plexus coordinates the muscular contractions of the GI tract?
The myenteric plexus (Auerbach’s plexus) controls the muscularis externa.
146
Why does the Valsalva maneuver help with defecation?
It increases intra-abdominal pressure by forced exhalation against a closed airway.
147
What activates pepsin in the stomach?
Gastric acid (HCl), which converts pepsinogen into active pepsin.
148
What type of metabolism occurs in the large intestine?
Passive metabolism via bacterial fermentation of undigested material.
149
Why do chemotherapy patients often experience nausea and diarrhea?
Chemotherapy damages rapidly dividing mucosal cells in the GI tract.
150
What is the role of bile salts in fat digestion?
They emulsify fats, increasing surface area for lipase activity.
151
What happens if a patient has a deficiency in trypsin?
Pancreatic enzymes remain inactive, impairing protein digestion.
152
What is the function of high-density lipoproteins (HDLs)?
They transport excess cholesterol from tissues to the liver for excretion.
153
What is the purpose of hepatic portal circulation?
It transports nutrient-rich blood from the GI tract to the liver for processing.
154
What is a dietary characteristic of saturated fats?
They are solid at room temperature and found in animal products like meat and dairy.
155
A patient with megaloblastic anemia lacks intrinsic factor. What gastric cells are likely damaged?
Parietal cells, which secrete intrinsic factor for vitamin B12 absorption.
156
What do pancreatic ductal cells secrete in response to acidic chyme in the duodenum?
Bicarbonate (HCO₃⁻), to neutralize gastric acid.
157
A tumor compresses the parotid gland and affects salivation. Which cranial nerve may be involved?
Cranial nerve VII (facial nerve), which innervates the muscles of facial expression and influences saliva.
158
What is the function of brush border enzymes in the small intestine?
They break down disaccharides and peptides into monosaccharides and amino acids.
159
What role does histamine play in the small intestine after acidic chyme enters?
It helps modulate intestinal activity, though more active in gastric acid secretion.
160
Why does ketosis develop in a patient with prolonged fasting or low carb intake?
Ketones accumulate as a byproduct of fatty acid breakdown for energy.
161
A diabetic patient with proteinuria and hypertension likely has damage to what renal structure?
The glomerulus, which is responsible for blood filtration in the kidney.
162
A trauma patient has right kidney bleeding after a blow to the lower back. What rib protects this area?
The 12th rib partially protects the right kidney, which lies retroperitoneally.
163
Which penile structure maintains an open urethra during ejaculation?
The corpus spongiosum prevents urethral compression during erection and ejaculation.
164
A patient underwent surgery to lengthen the penis. Which ligament is cut in this procedure?
The suspensory ligament, which connects the penis to the pubic symphysis.
165
Which muscle elevates the testes in response to cold temperatures?
The cremaster muscle raises the testes to regulate temperature.
166
A child is diagnosed with undescended testes. What is the medical term for this condition?
Cryptorchidism.
167
What two structures join to form the ejaculatory duct?
The ampulla of the vas deferens and the seminal vesicle.
168
Which structure contributes the majority of fluid in semen?
The seminal vesicles.
169
Where does sperm undergo final maturation and storage?
In the epididymis.
170
Trace the pathway of sperm from the testis to the epididymis.
Seminiferous tubule → straight tubule → rete testis → efferent ductules → epididymis.
171
Trace the arterial blood supply into the kidney.
Renal artery → segmental artery → interlobar artery → arcuate artery → cortical (interlobular) artery.
172
A young male has sudden testicular pain. What is the likely cause?
Testicular torsion, due to twisting of the spermatic cord.
173
A direct inguinal hernia passes medial to which artery?
The inferior epigastric artery.
174
Which male reproductive gland produces alkaline pre-ejaculate fluid to neutralize the urethra?
The bulbourethral (Cowper’s) gland.
175
Which muscle contracts to expel urine from the bladder?
The detrusor muscle.
176
What anatomical region of the bladder is associated with recurrent UTIs?
The trigone, a smooth area between ureteral and urethral openings.
177
Where is the first common site of kidney stone obstruction?
At the ureteropelvic junction (UPJ), where the renal pelvis meets the ureter.
178
Where do the renal arteries originate?
From the abdominal aorta.
179
What is the outermost fibrous layer of the kidney called?
The renal capsule.
180
Which muscle allows voluntary control over urination?
The external urethral sphincter.
181
What CT finding suggests inflammation of the kidney?
Perinephric fat stranding.
182
What structure collects urine from the major calyces and funnels it into the ureter?
The renal pelvis.
183
Where in the testis does sperm formation primarily occur?
In the seminiferous tubules.
184
Trace the flow of urine from the nephron to the ureter.
Renal cortex → renal medulla → minor calyx → major calyx → renal pelvis → ureter.
185
Which part of the urethra passes through the penis and ends at the external urethral orifice?
The spongy (penile) urethra, which terminates at the navicular fossa.
186
Why can’t a man achieve another erection shortly after ejaculation?
The refractory period follows ejaculation and is mediated by sympathetic activity.
187
What happens during inhibition of somatic neurons related to urination?
Relaxation of the external urethral sphincter allows urination.
188
What pressure drives fluid from the glomerulus into Bowman’s capsule?
Glomerular hydrostatic pressure.
189
A dehydrated patient needs ion replenishment to maintain blood pressure. Which ion is most important?
Sodium, which regulates extracellular fluid volume and pressure.
190
What is the easiest bedside way to monitor kidney function?
Urine output.
191
A diabetic patient has polyuria and polydipsia. What is the mechanism?
Osmotic diuresis due to glucose exceeding the reabsorption threshold.
192
What is the pathophysiology of central diabetes insipidus?
Inadequate secretion of antidiuretic hormone (ADH), causing non-osmotic water loss.
193
A woman who has been vomiting for 3 days is found to have increased bicarbonate. Why?
Metabolic alkalosis due to loss of gastric acid (HCl).
194
A man in septic shock has decreased serum bicarbonate. Why?
Metabolic acidosis due to lactic acid buildup and impaired perfusion.
195
Which transporter is responsible for solute reabsorption in the thick ascending loop of Henle?
NKCC (Na⁺-K⁺-2Cl⁻ cotransporter).
196
What is the effect of atrial natriuretic peptide (ANP)?
It decreases aldosterone secretion and promotes natriuresis.
197
Why do infants lack voluntary urination control?
The pontine micturition center does not fully mature until age 2–3.
198
What causes an erection physiologically?
Parasympathetic signals and nitric oxide cause vasodilation of penile arteries.
199
A man has low FSH and LH levels. What is the likely hormonal defect?
A deficiency in gonadotropin-releasing hormone (GnRH).
200
Why would an autoimmune attack on sustentocytes lead to infertility?
Sertoli (sustentacular) cells form the blood-testis barrier; immune exposure damages developing sperm.
201
Which cation acts as a buffer by shifting hydrogen ions into cells?
Potassium, which helps buffer acidosis.
202
A man with GI bleeding is hypotensive. What happens to kidney perfusion?
GFR decreases due to afferent arteriole constriction as a compensatory mechanism.
203
What is the role of the juxtaglomerular complex?
It senses low perfusion and secretes renin to regulate blood pressure.
204
What hormone increases calcium reabsorption in the distal convoluted tubule?
Parathyroid hormone (PTH).
205
Which hormone regulates water reabsorption in the collecting duct?
Antidiuretic hormone (ADH).
206
Ammonia is a byproduct of which process, and what is its buffering role?
It comes from glutamine metabolism and helps excrete acid while regenerating bicarbonate.
207
What is the main nitrogenous waste product in urine?
Urea, a byproduct of amino acid catabolism.
208
A 19-year-old male has delayed puberty and low testosterone. What is the likely cellular defect?
Leydig cell dysfunction, which impairs testosterone production.
209
What does glomerular filtration rate (GFR) represent?
The volume of plasma filtered by the glomeruli per minute.
210
A man with fluid overload and a lung mass has low sodium and concentrated urine. What is the diagnosis?
Syndrome of inappropriate antidiuretic hormone secretion (SIADH).
211
A man with diabetes and hypertension cannot achieve an erection. What is the cause?
Vascular insufficiency due to endothelial damage and impaired blood flow.
212
What ligament is the major stabilizer of the acromioclavicular (AC) joint?
The coracoclavicular ligament.
213
What part of a vertebra is the large, weight-bearing anterior portion?
The vertebral body.
214
What are the short, thick processes that project from the vertebral body and connect to the lamina?
The pedicles.
215
What is the inner gelatinous core of an intervertebral disc?
The nucleus pulposus.
216
Which ligament runs along the anterior side of the vertebral column and prevents hyperextension?
The anterior longitudinal ligament.
217
What is the upward projecting structure of the C2 vertebra (axis) called?
The dens (odontoid process).
218
What articulates with the dens of C2 on the atlas (C1)?
The facet for the dens on the anterior arch of C1.
219
What is the function of the menisci in the knee?
They absorb shock and reduce friction.
220
What is the role of the glenoid labrum in the shoulder joint?
It deepens the glenoid cavity to stabilize the humeral head.
221
What structure reduces friction as the biceps brachii tendon moves through the intertubercular groove?
The tendon sheath and transverse humeral ligament both help reduce friction and hold the tendon in place.
222
What is the function of a bursa?
To reduce friction between bones, tendons, and muscles at joints.
223
What is the flat, lateral extension of the scapula that articulates with the clavicle?
The acromion.
224
What hook-like projection on the scapula serves as a muscle attachment site?
The coracoid process.
225
What shallow socket on the scapula articulates with the humerus?
The glenoid cavity.
226
What is the superior notch on the manubrium of the sternum called?
The jugular notch.
227
Which ligament encircles the head of the radius and attaches to the ulna?
The annular ligament.
228
What is the prominent posterior projection of the ulna?
The olecranon.
229
What large back muscle extends, adducts, and medially rotates the arm?
The latissimus dorsi.
230
What shoulder muscle is a common site for intramuscular injections?
The deltoid.
231
Which muscles elevate the first two ribs during inspiration?
The scalenes.
232
Which neck muscle rotates the head and flexes the neck?
The sternocleidomastoid.
233
What major muscle of mastication elevates the mandible?
The masseter.
234
Which forehead muscle raises the eyebrows?
The frontalis.
235
Which joint connects the sacrum and ilium?
The sacroiliac joint.
236
What cartilaginous joint connects the two pubic bones?
The pubic symphysis.
237
What bony prominence is located on the lateral proximal femur?
The greater trochanter.
238
Which group of muscles extends the spine and maintains posture?
The erector spinae group.
239
Which muscles retract the scapula and are deep to the trapezius?
Rhomboid major and minor.
240
Which muscles adduct the shoulder?
Pectoralis major, latissimus dorsi, and teres major.
241
Which rotator cuff muscle is responsible for lateral rotation of the shoulder?
Teres minor.
242
Which rotator cuff muscle initiates shoulder abduction?
Supraspinatus.
243
Which muscle flexes the elbow?
Biceps brachii.
244
Which muscle abducts the thumb and is located on the thenar eminence?
Abductor pollicis brevis.
245
Which muscle lies on the posterior forearm and rotates the forearm laterally?
The supinator.
246
What structure is tapped during a knee-jerk reflex?
The patellar ligament.
247
What muscle group extends the knee?
The quadriceps femoris.
248
What is the prominent bony landmark on the distal tibia?
The medial malleolus.
249
What is the mortise in the ankle joint?
The bony arch formed by the tibia and fibula that articulates with the talus.
250
What ligament is commonly torn in an ankle inversion injury?
The anterior talofibular ligament (ATFL).
251
What is the bony prominence on the anterior tibia?
The tibial tuberosity.
252
Which lateral leg muscle everts the foot?
The fibularis longus.
253
Which muscle on the forearm aids in flexing the elbow and lies on the lateral side?
The brachioradialis.
254
Which phalange is closest to the hand or foot?
The proximal phalanx.
255
Which anterior leg muscle dorsiflexes the foot?
The tibialis anterior.
256
Which muscle is most superficial on the sole of the foot?
The flexor digitorum brevis.
257
Which muscle flexes the hip and inserts on the lesser trochanter?
The iliopsoas.
258
Which ligament limits hip abduction?
The pubofemoral ligament.
259
Which muscle is the primary extensor of the hip?
The gluteus maximus.
260
Which muscle is a primary calf muscle that flexes the knee and plantarflexes the ankle?
The gastrocnemius.
261
Which condition causes lateral knee pain from iliotibial band friction?
IT band syndrome.
262
What injury is suggested by a positive anterior drawer test?
An anterior cruciate ligament (ACL) tear.
263
Which foot bone is lateral and cube-shaped?
The cuboid.
264
What part of the vertebrae projects posteriorly and can be palpated?
The spinous process.
265
Where is the humerus most likely to fracture?
The surgical neck, just below the tuberosities.
266
What small, triangular bone is at the base of the vertebral column?
The coccyx.
267
Which muscle flexes the fingers at the metacarpophalangeal joints?
The lumbricals.
268
Which muscle is located in the gluteal region and is often involved in sciatic nerve irritation?
The piriformis.
269
Which small posterior knee muscle unlocks the knee joint?
The popliteus.
270
Which bone cell is responsible for bone resorption?
Osteoclasts.
271
Which nerve innervates the deltoid muscle and provides sensation over the shoulder?
The axillary nerve.
272
Which spinal level corresponds to thigh adduction and medial thigh sensation?
L2.
273
What is the role of creatine phosphate in muscle contraction?
It provides a quick source of ATP for short bursts of activity.
274
Which spinal level innervates the intrinsic muscles of the hand?
C8.
275
What part of a growing bone contains the growth plate?
The metaphysis.
276
A child with low growth hormone would have stunted growth due to impaired function of what area?
The epiphyseal plate (growth plate).
277
What is the process by which bones grow in diameter during childhood?
Appositional growth.
278
Where is bone marrow commonly sampled from during biopsy?
Spongy (cancellous) bone, such as the iliac crest.
279
A wheelchair-bound man with a stroke has muscle wasting. What is the cause?
Denervation atrophy due to lack of neural stimulation.
280
A child with upper motor neuron dysfunction may have what type of findings?
Spasticity, hyperreflexia, and muscle stiffness due to cerebral or corticospinal tract lesions.
281
What neuromuscular disorder involves antibodies against acetylcholine receptors and presents with eyelid weakness?
Myasthenia gravis, characterized by impaired neuromuscular transmission.
282
What is the smallest functional unit of a muscle fiber?
The sarcomere.
283
What structure propagates action potentials deep into the muscle fiber?
The T-tubule system.
284
Which bone membrane is responsible for delivering nutrients and anchoring tendons?
The periosteum.
285
Which bone membrane lines the medullary cavity and contains osteoblasts and osteoclasts?
The endosteum.
286
What type of muscle contraction shortens the muscle while maintaining constant force?
Concentric contraction.
287
Which protein walks along actin filaments during muscle contraction?
Myosin.
288
What ion binds to troponin to initiate contraction?
Calcium.
289
What is the role of tropomyosin in muscle contraction?
It blocks myosin binding sites on actin and regulates contraction.
290
What is tetany?
A state of continuous muscle contraction without relaxation due to rapid stimulation.
291
What is a motor unit?
A motor neuron and all the muscle fibers it innervates.
292
A patient has wrist drop. Which nerve is likely damaged?
The radial nerve.
293
What is the function of the sarcoplasmic reticulum in muscle cells?
It stores and releases calcium for muscle contraction.
294
What is central muscle fatigue caused by?
Impaired neuromuscular transmission or central nervous system drive.
295
What is peripheral muscle fatigue caused by?
Depletion of metabolic resources such as ATP.
296
What does the patellar reflex assess?
Integrity of the lower motor neurons in the L2–L4 spinal cord.
297
What is the external occipital protuberance used to identify?
The external occipital protuberance is a midline bony projection on the occipital bone and serves as an attachment site for the nuchal ligament.
298
What structure is involved in a patient with Parkinson’s disease showing degeneration in a midbrain structure?
The cerebral peduncles, which contain motor pathways connecting the cerebral cortex to the brainstem and spinal cord.
299
What bony structure is directly superior to the pituitary gland?
The sella turcica of the sphenoid bone.
300
Why is the sphenoid bone clinically significant?
The sphenoid bone houses the sella turcica and contributes to the orbits and cranial base; it contains several foramina transmitting critical structures.
301
What structure extends from the crista galli to the internal occipital protuberance?
The falx cerebri, which separates the two cerebral hemispheres.
302
Which muscle is likely affected in a child with difficulty forming a tight lip seal?
Orbicularis oris, which encircles the mouth and controls lip movements.
303
Through which foramen does the middle meningeal artery pass?
Foramen spinosum.
304
Through which foramen does cranial nerve X exit the skull?
Jugular foramen.
305
What structures could be affected by a mass compressing the jugular foramen?
Cranial nerves IX, X, XI and the internal jugular vein.
306
What structure helps anchor the spinal cord inferiorly?
Filum terminale.
307
What venous structure likely facilitated the spread of an intracranial infection from a scalp laceration?
Emissary veins, which connect extracranial veins to dural venous sinuses.
308
Where is the most likely level of compression in a patient with saddle anesthesia and bladder dysfunction?
L4-L5, compressing the cauda equina.
309
What brain region is likely affected in a man with right-sided weakness and expressive aphasia after a stroke?
Left primary motor cortex and Broca’s area in the dominant hemisphere.
310
Which spinal tract is likely affected in a patient with difficulty sensing vibration and proprioception?
The dorsal column-medial lemniscal pathway.
311
What spinal tract is likely involved in a patient with hyperreflexia and spasticity?
Corticospinal tract (not reticulospinal).
312
What nerve is likely damaged near the parotid gland in a patient with facial paralysis and difficulty salivating?
Facial nerve (CN VII).
313
Which cranial nerve is most likely involved in a patient with diplopia and inability to adduct the right eye?
Oculomotor nerve (CN III).
314
What brainstem structure helps regulate consciousness?
The reticular formation.
315
Which sinus is most commonly involved in the spread of a facial infection intracranially?
The cavernous sinus.
316
Which muscle is likely damaged in a patient who cannot purse their lips after facial trauma?
Orbicularis oris, responsible for closing and puckering the lips.
317
What type of spinal curvature is normally seen in the cervical and lumbar regions?
Lordosis.
318
What function is likely impaired in a patient with loss of sensation in the left postcentral gyrus?
Primary somatosensory perception—touch, proprioception, and vibration.
319
What brain structure is likely affected in a patient with short-term memory loss?
Hippocampus.
320
The caudate and putamen are part of what larger group?
The basal ganglia; together they form the striatum.
321
What structure is affected in a patient with insomnia and disrupted circadian rhythms near the posterior third ventricle?
The pineal gland, which regulates the sleep-wake cycle via melatonin.
322
What white matter structure allows communication between the left and right cerebral hemispheres?
Corpus callosum.
323
What part of the brain is affected by infarction in the anterior cerebral artery territory?
The medial portion of the frontal lobes and superior medial parietal lobes.
324
What foramen may have been affected by damage to the middle meningeal artery in a trauma patient with basilar skull fracture?
Foramen spinosum.
325
What two paired arteries unite to form the basilar artery?
The vertebral arteries.
326
What space would the brain herniate through in a case of increased intracranial pressure?
Foramen magnum.
327
What is the most likely diagnosis for a post-trauma patient with a lucid interval followed by rapid neurological decline?
Epidural hematoma due to rupture of the middle meningeal artery.
328
Which fissure separates the right and left cerebral hemispheres?
The longitudinal fissure.
329
Which artery connects the posterior cerebral artery to the internal carotid system?
Posterior communicating artery.
330
What bone is most likely fractured in a patient with facial trauma who has difficulty chewing and numbness on the cheekbone?
The zygomatic bone.
331
What autonomic functions is the medulla oblongata responsible for?
Cardiovascular regulation, respiratory rhythm, and reflex centers for vomiting, coughing, and sneezing.
332
What structure shows cerebrospinal fluid within a C-shaped cavity inside the cerebral hemispheres?
The lateral ventricles.
333
What autonomic function is preserved in a man with a traumatic spinal cord injury at T3?
Parasympathetic digestion in large intestines
334
What is the function of dendrites?
Receive chemical signals from other neurons
335
What ion is responsible for generating an action potential when threshold becomes more positive?
Sodium
336
What ion is responsible for sending vesicles?
Calcium
337
What reflex is triggered when you tap on the patellar ligament?
Stretch reflex
338
What reflex is triggered when you step on a piece of broken glass and lift your leg?
Flexor extensor reflex
339
What is the function of an interneuron?
Integrates afferent and efferent input in the spinal cord (no involvement of the brain)
340
What is an inhibitor of acetylcholinesterase?
Excess Ach in the synapse
341
What neurotransmitter is found on sympathetic postsynaptic ganglion?
Norepinephrine
342
What is the period of time when another signal cannot be sent?
Absolute refractory
343
What is saltatory conduction?
Action potential jumps between nodes of Ranvier
344
What is temporal summation?
When multiple signals are sent from the same neuron over time
345
What does it mean when you have a heart attack and feel pain in your arm?
Referred pain from visceral organ
346
What neurotransmitter stimulates muscle contraction and inhibits the heart?
Ach
347
What is the function of the hypothalamus in the ANS?
Main integrative center
348
What neurotransmitter makes a guy like using methamphetamine?
Dopamine
349
What is the mechanism of action for serotonin syndrome?
Excessive levels of serotonin
350
What receptor does a bronchodilator act on during an asthma attack?
B2
351
What is the most abundant cell in the CNS and the BBB?
Astrocytes
352
What is the ciliated cell that lines cavities and produces CSF?
Ependymal cells
353
What is a painless growth on the forearm?
Schwannoma
354
What cell is responsible for myelination in the peripheral nervous system?
Schwann cell
355
What parasympathetic innervation is involved in issues with salivation and pupil dilation?
Craniosacral
356
How did rabies get into the CNS?
Retrograde axonal transport
357
What is the main excitatory neurotransmitter of the CNS?
Glutamate
