Anatomy
4 questionsWhich of the following statements about the adductors of the thigh is correct?
Which of the following is a tributary of the coronary sinus?
Which of the following structures is located within the cavernous sinus?
Which structure(s) passes behind the inguinal ligament:
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 31: Which of the following statements about the adductors of the thigh is correct?
- A. The main blood supply to the adductors is from the profunda femoris artery.
- B. Adductor brevis is the shortest adductor muscle (Correct Answer)
- C. The ischial head of adductor magnus is not an adductor muscle.
- D. The adductor magnus is the largest muscle in the thigh.
Explanation: ***Adductor brevis is the shortest adductor muscle*** - The **adductor brevis** is the shortest muscle among the adductor group in the thigh. - The three main adductors by size: **adductor magnus** (longest and largest) > **adductor longus** (intermediate) > **adductor brevis** (shortest). - Adductor brevis lies deep to pectineus and adductor longus, and plays a key role in **thigh adduction**. *The ischial head of adductor magnus is not an adductor muscle.* - The **ischial/hamstring part of adductor magnus** does contribute to adduction despite its primary action being hip extension like other hamstrings. - It also acts on the **hip joint** to extend the thigh, but its adductor action is functionally important. *The main blood supply to the adductors is from the profunda femoris artery.* - While the **profunda femoris artery (deep femoral artery)** supplies the posterior and lateral compartments of the thigh, the adductors primarily receive blood from the **obturator artery** and branches of the femoral artery. - The **obturator artery** is specifically known for supplying the adductor muscles of the medial compartment. *The adductor magnus is the largest muscle in the thigh.* - The **adductor magnus** is the largest muscle in the adductor group, but not the largest muscle in the entire thigh. - The **quadriceps femoris group** (vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris) collectively forms the largest muscle mass in the thigh.
Question 32: Which of the following is a tributary of the coronary sinus?
- A. Anterior cardiac vein
- B. Smallest cardiac vein
- C. Thebesian vein
- D. Great cardiac vein (Correct Answer)
Explanation: ***Great cardiac vein*** - The **great cardiac vein** is a major tributary that drains into the **coronary sinus**, carrying deoxygenated blood from the anterior and left ventricular walls [1]. - It travels alongside the **anterior interventricular artery** (LAD) and then wraps around the left side of the heart to join the coronary sinus [1]. *Anterior cardiac vein* - The **anterior cardiac veins** typically collect blood directly into the **right atrium**, bypassing the coronary sinus [1]. - They primarily drain the anterior wall of the right ventricle. *Thebesian vein* - **Thebesian veins** (or venae cordis minimae) are small veins that drain blood from the **myocardium directly into the heart chambers**, predominantly the atria [1]. - They represent a direct communication between the myocardial capillaries and the heart chambers, not tributaries of the coronary sinus. *Smallest cardiac vein* - The term "smallest cardiac vein" is often used synonymously with **Thebesian veins** [1]. - These veins empty directly into the **heart chambers**, serving as an ancillary drainage system, rather than converging into the coronary sinus.
Question 33: Which of the following structures is located within the cavernous sinus?
- A. Maxillary division of V nerve
- B. Mandibular division of V nerve
- C. Internal carotid artery (Correct Answer)
- D. Facial nerve
Explanation: ***Internal carotid artery*** - The **internal carotid artery** passes **through the lumen** of the cavernous sinus, which is a dural venous sinus located on either side of the sella turcica. - Along with the **abducens nerve (CN VI)**, the internal carotid artery is one of only two structures that passes directly through the cavernous sinus cavity itself. - This is the **most accurate answer** as it traverses the actual sinus space, not just the wall. *Maxillary division of V nerve* - The **maxillary division of the trigeminal nerve (V2)** runs within the **lateral wall** of the cavernous sinus, not through its lumen. - While technically "within" the sinus structure, it is embedded in the dural wall rather than passing through the blood-filled cavity. - This nerve exits the skull through the **foramen rotundum**. - Other nerves in the lateral wall include **CN III, CN IV, and V1**. *Mandibular division of V nerve* - The **mandibular division of the trigeminal nerve (V3)** does not pass through or near the cavernous sinus. - It exits the middle cranial fossa directly via the **foramen ovale**, positioned inferior and separate from the cavernous sinus. - V3 is the only division of the trigeminal nerve that does not have any relationship with the cavernous sinus. *Facial nerve* - The **facial nerve (CN VII)** has no anatomical relationship with the cavernous sinus. - It enters the temporal bone through the **internal acoustic meatus**, travels through the facial canal, and exits via the **stylomastoid foramen**. - Its course is entirely separate from the cavernous sinus region.
Question 34: Which structure(s) passes behind the inguinal ligament:
- A. Femoral branch of genitofemoral nerve
- B. Femoral vein
- C. Psoas major
- D. All of the options (Correct Answer)
Explanation: ***Correct: All of the options*** All three structures pass deep to (behind) the inguinal ligament as they transition from the pelvis/abdomen into the thigh [1]. The inguinal ligament forms the superior border of the femoral triangle [1]. ***Femoral branch of genitofemoral nerve (Correct)*** - Pierces the **psoas major** muscle and descends along its anterior surface - Passes through the **lacuna musculorum** (lateral compartment) deep to the inguinal ligament - Lies **lateral to the femoral artery** - Provides sensory innervation to the skin over the femoral triangle ***Femoral vein (Correct)*** - Continuation of the popliteal vein from the lower limb - Passes through the **lacuna vasorum** (medial compartment/femoral canal) within the **femoral sheath** - Located **medial to the femoral artery** behind the inguinal ligament [1] - Carries deoxygenated blood back to the heart via the external iliac vein ***Psoas major (Correct)*** - Major hip flexor muscle originating from lumbar vertebrae (T12-L5) - Passes through the **lacuna musculorum** deep to the inguinal ligament - Located **lateral to the femoral vessels** - Combines with iliacus to form iliopsoas, inserting on the lesser trochanter of femur
Biochemistry
2 questionsWhich of the following enzymes is not part of the fatty acid synthase complex?
What is the immediate source of energy for cellular processes?
NEET-PG 2015 - Biochemistry NEET-PG Practice Questions and MCQs
Question 31: Which of the following enzymes is not part of the fatty acid synthase complex?
- A. Enoyl reductase
- B. Ketoacyl synthase
- C. Acetyl-CoA carboxylase (Correct Answer)
- D. Ketoacyl reductase
Explanation: ***Acetyl-CoA carboxylase*** - **Acetyl-CoA carboxylase (ACC)** is a crucial enzyme in fatty acid synthesis, catalyzing the committed and rate-limiting step of converting **acetyl-CoA to malonyl-CoA**. - While essential for providing the substrates for fatty acid synthase, ACC is a **separate, distinct enzyme** and not structurally part of the fatty acid synthase complex itself. *Ketoacyl reductase* - **Ketoacyl reductase** is an integral enzymatic domain of the fatty acid synthase complex. - It catalyzes the **first reduction step** in the fatty acid synthesis cycle, converting a $\beta$-ketoacyl group to a $\beta$-hydroxyacyl group using NADPH. *Enoyl reductase* - **Enoyl reductase** is an intrinsic enzymatic domain of the fatty acid synthase complex. - It catalyzes the **second reduction step**, converting a trans- $\alpha$, $\beta$-enoyl group to a saturated acyl group using NADPH. *Ketoacyl synthase* - **Ketoacyl synthase (or $\beta$-ketoacyl-ACP synthase)** is a core enzymatic domain within the fatty acid synthase complex. - It catalyzes the **condensation reaction** between the growing acyl chain and malonyl-ACP, forming a $\beta$-ketoacyl-ACP.
Question 32: What is the immediate source of energy for cellular processes?
- A. Cori's cycle
- B. HMP
- C. ATP (Correct Answer)
- D. TCA cycle
Explanation: ***ATP*** - **Adenosine triphosphate (ATP)** is the direct and immediate source of energy for almost all cellular processes, including **muscle contraction**, **active transport**, and **biosynthesis**. - Its high-energy phosphate bonds release energy upon hydrolysis, driving various cellular functions. *Cori's cycle* - The **Cori cycle** involves the interconversion of **lactate** and **glucose** between the muscle and the liver to regenerate glucose stores. - It is an important metabolic pathway for glucose homeostasis during anaerobic conditions, but it does not directly provide immediate energy for cellular processes. *HMP* - The **Hexose Monophosphate Pathway (HMP)**, also known as the **pentose phosphate pathway**, primarily produces **NADPH** and **ribose-5-phosphate**. - While it generates NADPH for reductive biosynthesis and protects against oxidative stress, it is not an immediate source of energy. *TCA cycle* - The **Tricarboxylic Acid (TCA) cycle**, or Krebs cycle, is a central metabolic pathway that oxidizes **acetyl-CoA** to produce **ATP**, **NADH**, and **FADH2**. - While it is a major producer of ATP, it is not the *immediate* source; instead, it generates the precursors that fuel oxidative phosphorylation to produce ATP.
Dental
1 questionsEpulis arises from -
NEET-PG 2015 - Dental NEET-PG Practice Questions and MCQs
Question 31: Epulis arises from -
- A. Enamel
- B. Root of teeth
- C. Gingiva (Correct Answer)
- D. Pulp
Explanation: ***Gingiva*** - **Epulis** refers to a localized, tumor-like enlargement of the **gingiva** (gum tissue). - These lesions are typically inflammatory or reactive in nature, arising from the connective tissue of the gum. *Enamel* - **Enamel** is the hard, outermost protective layer of the tooth crown, which is of ectodermal origin. - Lesions originating from enamel itself are rare and typically involve developmental defects or structural damage, not soft tissue growths like epulis. *Root of teeth* - The **root of the teeth** is embedded in the alveolar bone and covered by cementum, with the surrounding structures including the periodontal ligament and alveolar bone. - While infections or cysts can arise from the root, epulis specifically describes a growth of the overlying **gingival tissue**. *Pulp* - The **pulp** is the soft tissue inside the tooth containing nerves, blood vessels, and connective tissue. - Pathologies originating from the pulp are typically infectious (pulpitis), degenerative, or involve growth of odontogenic tissues (e.g., pulp polyps within the tooth chamber), not surface gingival lesions.
Dermatology
1 questionsPhrynoderma is primarily associated with a deficiency of which of the following?
NEET-PG 2015 - Dermatology NEET-PG Practice Questions and MCQs
Question 31: Phrynoderma is primarily associated with a deficiency of which of the following?
- A. Essential fatty acid
- B. Vitamin A (Correct Answer)
- C. Vitamin D
- D. Niacin
Explanation: ***Vitamin A*** - **Phrynoderma** (toad skin) has been **classically attributed to vitamin A deficiency** in traditional medical literature and was the accepted answer in historical examinations. - It presents as **follicular hyperkeratosis** with dry, scaly, rough skin having prominent hair follicles with a sandpaper-like texture. - However, **modern evidence** suggests phrynoderma is a **multifactorial condition** often involving **multiple nutritional deficiencies**, with vitamin A being one important contributor among others. *Essential fatty acid* - Deficiency of **essential fatty acids** (linoleic and alpha-linolenic acid) causes **skin dryness, flakiness, and follicular hyperkeratosis**. - **Recent studies** indicate EFA deficiency may play a **significant role** in phrynoderma, particularly in developing countries where multiple nutritional deficiencies coexist. - The clinical presentation can closely mimic vitamin A deficiency-related skin changes. *Vitamin D* - Deficiency of **vitamin D** primarily causes **rickets** in children and **osteomalacia** in adults with bone pain, muscle weakness, and skeletal deformities. - While vitamin D has roles in skin health, its deficiency does not directly cause the follicular hyperkeratosis characteristic of phrynoderma. *Niacin* - **Niacin (vitamin B3)** deficiency causes **pellagra** with the classic \"3 Ds\": **dermatitis, diarrhea, and dementia**. - Pellagra dermatitis is typically **symmetrical in sun-exposed areas** with redness, scaling, and hyperpigmentation—distinctly different from the follicular pattern of phrynoderma.
Ophthalmology
1 questionsLarge, white keratic precipitates (mutton-fat KPs) are characteristically seen in?
NEET-PG 2015 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 31: Large, white keratic precipitates (mutton-fat KPs) are characteristically seen in?
- A. Hemorrhagic uveitis
- B. Old healed uveitis
- C. Granulomatous uveitis (Correct Answer)
- D. Acute anterior uveitis
Explanation: ***Granulomatous uveitis*** - **Mutton-fat keratic precipitates (KPs)** are large, greasy-appearing white deposits on the corneal endothelium, characteristic of **granulomatous inflammation**. - These KPs are composed of macrophages and epithelioid cells, reflecting a **chronic, cell-mediated immune response** seen in granulomatous conditions. *Hemorrhagic uveitis* - This condition involves significant **intraocular bleeding**, which would manifest as hyphema or vitreous hemorrhage, not mutton-fat KPs. - While inflammation may be present, the defining feature is blood, which obscures vision differently than KPs. *Old healed uveitis* - After uveitis heals, KP morphology can change, often appearing smaller, more pigmented, or forming distinct patterns such as **Arlt's triangle**, but not typically actively large, white mutton-fat KPs. - Healed KPs often reflect a less active or resolved inflammatory process, unlike fresh mutton-fat KPs. *Acute anterior uveitis* - This typically presents with smaller, finer, and more numerous **non-granulomatous KPs** (sometimes called "stellate KPs"), in contrast to the large, greasy mutton-fat KPs. - The inflammation is usually acute and less focally organized compared to granulomatous forms.
Pediatrics
1 questionsWhich of the following is not found in DiGeorge's syndrome?
NEET-PG 2015 - Pediatrics NEET-PG Practice Questions and MCQs
Question 31: Which of the following is not found in DiGeorge's syndrome?
- A. Eczema (Correct Answer)
- B. Tetany
- C. T cell lymphopenia
- D. Mucocutaneous candidiasis
Explanation: ***Eczema*** - **Eczema** is NOT a recognized feature of **DiGeorge syndrome** (22q11.2 deletion syndrome). - While individuals with immunodeficiencies may experience various skin conditions, eczema is specifically associated with conditions like **Hyper-IgE syndrome, Wiskott-Aldrich syndrome**, or atopic disorders, not DiGeorge's. - DiGeorge's follows the **CATCH-22 mnemonic**: Cardiac defects, Abnormal facies, Thymic hypoplasia, Cleft palate, Hypocalcemia, 22q11 deletion. *Tetany* - **Tetany IS found** in DiGeorge's syndrome due to **hypocalcemia** from parathyroid gland hypoplasia or aplasia. - The lack of parathyroid hormone leads to **low serum calcium levels**, resulting in increased neuromuscular excitability and tetany. *T cell lymphopenia* - **T-cell lymphopenia IS found** in DiGeorge's syndrome due to **thymic hypoplasia or aplasia**. - The primary immunological defect is **T-cell deficiency**, leading to increased susceptibility to viral, fungal, and intracellular bacterial infections. - B-cell numbers are typically normal, though antibody responses may be impaired due to lack of T-cell help. *Mucocutaneous candidiasis* - **This IS found** in patients with DiGeorge's syndrome as an opportunistic infection due to **T-cell immunodeficiency**. - The impaired **cellular immunity** makes individuals highly susceptible to fungal infections like *Candida albicans* affecting mucous membranes and skin.