NEET-PG 2013 Practice Questions

Q: What is the number of muscles in the middle ear?

Two. ***Two*** - The middle ear houses two muscles: the **tensor tympani** and the **stapedius muscle** [1]. - These muscles play a crucial role in the **acoustic reflex**, protecting the inner ear from loud sounds. *One* - This option is incorrect as there are two muscles, not one, involved in middle ear function [1]. - Specifying one muscle would neglect the complementary role of the other in the acoustic reflex. *Three* - This option is incorrect because the middle ear only contains two muscles [1]. - There are no additional muscles associated with the ossicles or tympanic membrane. *Four* - This option is incorrect as the middle ear is only comprised of the **tensor tympani** and **stapedius** muscles [1]. - The number four is not associated with the muscular anatomy of the middle ear.

Q: Which of the following structures pass through the superior orbital fissure?

All of the options. ***All of the options*** - The **superior orbital fissure** is a key opening in the skull that allows passage of several important cranial nerves and vessels into the orbit. - The **oculomotor nerve**, **trochlear nerve**, and **superior ophthalmic vein** are all established structures that pass through this fissure. *Oculomotor nerve* - The **oculomotor nerve (CN III)** passes through the superior orbital fissure to innervate most of the extrinsic eye muscles. - It controls movements such as **adduction**, **elevation**, and **depression** of the eyeball, and also innervates the **levator palpebrae superioris** muscle for eyelid elevation [1]. *Trochlear nerve* - The **trochlear nerve (CN IV)**, which innervates the **superior oblique muscle**, also passes through the superior orbital fissure. - The superior oblique muscle is responsible for **intorsion** and **depression** of the eye, particularly when the eye is adducted [1]. *Superior ophthalmic vein* - The **superior ophthalmic vein** drains blood from structures within the orbit and passes through the superior orbital fissure to drain into the **cavernous sinus**. - This vein provides a connection between the facial veins and the cavernous sinus, which can be clinically relevant in cases of infection spread.

Q: Which of the following is not a tributary of the cavernous sinus?

Inferior cerebral vein. Detailed anatomical knowledge of the dural venous sinuses is required to answer this question. Venous drainage from the brain by way of the deep veins and dural sinuses typically empties principally into the internal jugular veins, though blood also drains via the ophthalmic and pterygoid venous plexuses [1]. ***Inferior cerebral vein*** - The **inferior cerebral veins** drain the inferior surface of the cerebral hemispheres and typically empty into the **basal vein of Rosenthal**, **transverse sinus**, or other dural sinuses. - They do **not directly drain** into the cavernous sinus, making this the correct answer. - While some small inferior cerebral veins may occasionally communicate with the cavernous sinus, they are not considered standard tributaries. *Central vein of retina* - The **central vein of retina** drains the retina and exits the eye through the optic nerve. - It drains into the **superior ophthalmic vein**, which then empties into the cavernous sinus. - It is an **indirect tributary** via the superior ophthalmic vein, not a direct tributary itself. *Sphenoparietal sinus* - The **sphenoparietal sinus** is a dural venous sinus that runs along the posterior edge of the lesser wing of the sphenoid bone. - It is a **direct tributary** that drains anteriorly into the cavernous sinus. - This is one of the standard tributaries listed in anatomical texts. *Superior ophthalmic vein* - The **superior ophthalmic vein** is the **major tributary** draining orbital structures including the eyeball, extraocular muscles, and eyelids. - It passes posteriorly through the **superior orbital fissure** to drain directly into the cavernous sinus. - This is the most clinically significant tributary, as infections can spread from the face to the cavernous sinus via this route.

Q: What anatomical structure does the pineal gland form part of?

Part of the roof of the third ventricle. **_Part of the roof of the third ventricle_** - The **pineal gland** is a small, pinecone-shaped endocrine gland that forms part of the **roof of the third ventricle** [1]. - It is attached to the roof by the **pineal stalk** and projects posteriorly from the **epithalamus**. - The roof of the third ventricle consists of the **tela choroidea**, the **pineal gland**, and the **choroid plexus** [1]. - The pineal gland regulates circadian rhythms through **melatonin** secretion. *Part of the posterior wall of the third ventricle* - The **posterior wall** of the third ventricle is formed by the **posterior commissure**, the **pineal recess**, and the **habenular commissure**. - While the pineal gland is located posteriorly, it is anatomically classified as part of the roof, not the posterior wall itself. *Part of the anterior wall of the third ventricle* - The **anterior wall** is formed by the **lamina terminalis**, **anterior commissure**, and columns of the fornix. - This is located at the opposite end of the third ventricle from the pineal gland. *Part of the floor of the third ventricle* - The **floor** is formed by structures of the **hypothalamus**, including the **optic chiasm**, **tuber cinereum**, **infundibulum**, and **mammillary bodies**. - The pineal gland is situated dorsally (superiorly), not in the floor.

Q: Type 3 respiratory failure occurs due to ?

Post-operative atelectasis. ***Post-operative atelectasis*** - **Type 3 respiratory failure**, also known as **perioperative respiratory failure**, is characterized by hypoxemia occurring typically after surgery. - **Atelectasis**, the collapse of lung tissue, is a common cause of hypoxemia in the post-operative period due to shallow breathing, pain, and anesthesia affecting lung volumes. *Kyphoscoliosis* - This condition leads to a **restrictive lung disease** due to chest wall deformity, causing chronic respiratory failure. [1] - It more typically results in **Type 2 respiratory failure** (hypercapnic) due to impaired ventilation over time. [1] *Flail chest* - Flail chest is a severe chest wall injury causing paradoxical movement, leading to **acute respiratory failure**. - It is often associated with **Type 1 (hypoxemic)** or **Type 2 (hypercapnic)** respiratory failure due to trauma-induced lung injury and impaired mechanics. *Pulmonary fibrosis* - This is a progressive interstitial lung disease causing **restrictive ventilatory defect** and impaired gas exchange. - It leads to chronic **Type 1 respiratory failure** (hypoxemic) as the lung tissue becomes stiff and scarred.

Q: Which of the following statements about sickle cell anemia is false?

Ringed sideroblasts are associated with sickle cell anemia.. ***Ringed sideroblast*** - **Ringed sideroblasts** are not typically associated with sickle cell anemia; they are indicative of disorders like **sideroblastic anemia**. - In sickle cell anemia, the primary findings include **hemolysis** and ineffective erythropoiesis, not ringed sideroblasts [3]. *Howell jolly bodies* - These bodies are remnants of nuclear material and can be found in individuals with **spleen dysfunction**, which can occur in sickle cell anemia [1]. - They are actually a common finding due to **hyposplenism** or **asplenia** in patients with sickle cell disease [2]. *Sickle cells* - The presence of **sickle-shaped red blood cells** is a hallmark of sickle cell anemia, caused by the mutation in the **beta-globin chain** [3]. - These sickle cells are responsible for the characteristic complications of the disease, such as **vaso-occlusive crises** [1][3]. *Target cells* - Target cells, or **codocytes**, are often seen in disorders like **thalassemia** and liver disease, and can also be present in sickle cell anemia. - They are formed due to an increase in the **surface area to volume ratio** of red blood cells, often secondary to **membrane abnormalities** seen in sickle cell changes [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 644-646. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 570-571. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 598-599.

Q: Which of the following statements about Polycythemia vera is false?

Increased LAP score. ***Decrease LAP score*** - In polycythemia vera, the **LAP (leukocyte alkaline phosphatase) score** is typically increased, indicating more mature leukocytes. - A **decrease in LAP score** is not consistent with the disease, making this statement incorrect. *Increased platelets* - Polycythemia vera often results in **thrombocytosis**, characterized by increased platelet counts [1]. - This is a common feature of the disorder, reflecting overproduction of blood cells in the bone marrow. *Leucocytosis* - Patients with polycythemia vera frequently exhibit **leucocytosis**, or increased white blood cell counts, due to hypercellularity of the bone marrow [1]. - This is an important aspect of the disease, often seen alongside increases in red blood cells and platelets. *Increased vit B12* - An elevation in **vitamin B12** levels can occur in polycythemia vera, often due to increased binding proteins. - This is a well-recognized phenomenon associated with the increased cell turnover in this condition. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 626-627.

Q: What is the typical bone marrow finding in myelofibrosis?

Dry tap (hypocellular). ***Dry tap (hypocellular)*** - In myelofibrosis, the bone marrow is often **hypocellular** due to fibrosis [1][2], leading to a **dry tap** during aspiration. - The presence of **reticulin** and collagen deposition replaces normal hematopoietic cells [2], resulting in ineffective hematopoiesis. *Thrombocytosis* - Myelofibrosis typically leads to **thrombocytopenia**, not thrombocytosis, due to ineffective megakaryopoiesis and splenic sequestration. - Though elevated platelets can occur, they are generally a **secondary response** to the disease and not a hallmark finding. *Megaloblastic cells* - Megaloblastic changes are associated with **vitamin B12** or **folate deficiencies**, which do not occur in myelofibrosis. - In myelofibrosis, the predominant issue is **marrow fibrosis** [1][2], which does not lead to megaloblastosis. *Microcytic cells* - Microcytic cells are commonly linked to **iron deficiency anemia**, not myelofibrosis. - Myelofibrosis typically results in **variable red cell morphology** [1], but microcytic anemia is not a primary characteristic. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 628-629. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 615-616.

Q: What is the minimum fluid urine output for neutral solute balance?

400 ml. ***400 ml*** - The kidneys must excrete approximately **600 mOsm of solutes daily** to maintain neutral solute balance. - With a maximum urine concentrating ability of **1200-1400 mOsm/L**, the minimum volume required is calculated as: 600 mOsm ÷ 1400 mOsm/L = **428 ml**. - Therefore, **400 ml** is the conventionally accepted minimum urine output for neutral solute balance. - Below this volume, even with maximal concentration, solute excretion would be inadequate. *300 ml* - **300 ml** would be insufficient to excrete the 600 mOsm daily solute load even at maximal concentration (300 × 1400 = 420 mOsm only). - This volume would lead to accumulation of solutes and **azotemia** (elevated BUN and creatinine). *500 ml* - While **500 ml** would certainly be adequate for solute excretion, it exceeds the calculated minimum of ~428 ml. - The question asks for the *minimum* volume, making **400 ml** the more precise answer according to standard textbooks. *750 ml* - **750 ml** is well above the minimum required for neutral solute balance. - This volume represents normal physiological urine output but is not the minimum threshold for maintaining solute balance.

Q: What does Boyle's Law state?

PV = constant. ***PV = constant*** - **Boyle's Law** states that at constant temperature, the pressure and volume of a gas are inversely proportional. - Mathematically expressed as **PV = constant** or **P₁V₁ = P₂V₂** - This means that if the volume of a gas decreases, its pressure increases proportionally, and vice versa. - **Clinically relevant** in understanding lung mechanics during respiration - as thoracic volume increases during inspiration, intrapulmonary pressure decreases, allowing air to flow in. *Pressure divided by temperature is constant.* - This describes **Gay-Lussac's Law** (P/T = constant), which relates pressure and temperature at constant volume. - Shows the direct relationship between pressure and temperature. *Volume divided by temperature is constant.* - This statement describes **Charles's Law** (V/T = constant), which relates the volume and temperature of a gas at constant pressure. - Indicates a direct relationship between volume and temperature. *Pressure multiplied by volume equals the number of moles times the gas constant times temperature.* - This represents the **Ideal Gas Law**: PV = nRT - Combines Boyle's, Charles's, and Avogadro's laws to relate pressure, volume, temperature, and the number of moles of a gas.

Question 1

What is the number of muscles in the middle ear?

Accepted Answer

Two

Answer

One

Answer

Three

Answer

Four

Question 2

Which of the following structures pass through the superior orbital fissure?

Accepted Answer

All of the options

Answer

Oculomotor nerve

Answer

Trochlear nerve

Answer

Superior ophthalmic vein

Question 3

Which of the following is not a tributary of the cavernous sinus?

Accepted Answer

Inferior cerebral vein

Answer

Central vein of retina

Answer

Sphenoparietal sinus

Answer

Superior ophthalmic vein

Question 4

What anatomical structure does the pineal gland form part of?

Accepted Answer

Part of the roof of the third ventricle

Answer

Part of the anterior wall of the third ventricle

Answer

Part of the floor of the third ventricle

Answer

Part of the posterior wall of the third ventricle

Question 5

Type 3 respiratory failure occurs due to ?

Accepted Answer

Post-operative atelectasis

Answer

Kyphoscoliosis

Answer

Flail chest

Answer

Pulmonary fibrosis

Question 6

Which of the following statements about sickle cell anemia is false?

Accepted Answer

Ringed sideroblasts are associated with sickle cell anemia.

Answer

Sickle cells are present in sickle cell anemia.

Answer

Target cells are commonly seen in sickle cell anemia.

Answer

Howell Jolly bodies can be found in sickle cell anemia.

Question 7

Which of the following statements about Polycythemia vera is false?

Accepted Answer

Increased LAP score

Answer

Increased vitamin B12 levels

Answer

Leukocytosis is present

Answer

Increased platelet count

Question 8

What is the typical bone marrow finding in myelofibrosis?

Accepted Answer

Dry tap (hypocellular)

Answer

Megaloblastic cells

Answer

Microcytic cells

Answer

Thrombocytosis

Question 9

What is the minimum fluid urine output for neutral solute balance?

Accepted Answer

400 ml

Answer

300 ml

Answer

750 ml

Answer

500 ml

Question 10

What does Boyle's Law state?

Accepted Answer

PV = constant

Answer

Pressure divided by temperature is constant.

Answer

Volume divided by temperature is constant.

Answer

Pressure multiplied by volume equals the number of moles times the gas constant times temperature.

NEET-PG 2013

Anatomy

Internal Medicine

Pathology

Physiology