Anatomy
4 questionsWhat is the nerve supply to the muscles of the flexor compartment of the arm?
The blood supply to femoral head is mostly by?
Which of the following muscles is not in the pectoral region?
Which of the following statements about the mammary gland is false?
NEET-PG 2013 - Anatomy NEET-PG Practice Questions and MCQs
Question 141: What is the nerve supply to the muscles of the flexor compartment of the arm?
- A. Musculocutaneous nerve (Correct Answer)
- B. Median nerve
- C. Radial nerve
- D. Ulnar nerve
Explanation: ***Musculocutaneous nerve*** - The **musculocutaneous nerve** is the primary nerve supplying all three muscles in the **flexor compartment of the arm**: the **biceps brachii**, **brachialis**, and **coracobrachialis**. - Its motor branches innervate these muscles, allowing for **flexion at the elbow** and **supination of the forearm**. *Median nerve* - The **median nerve** primarily innervates most muscles in the **flexor compartment of the forearm**, not the arm. - It plays a crucial role in **wrist and finger flexion**, as well as movements of the **thenar eminence**. *Radial nerve* - The **radial nerve** is the main nerve for the **extensor compartment of the arm and forearm**. - It is responsible for **elbow, wrist, and finger extension**. *Ulnar nerve* - The **ulnar nerve** primarily supplies intrinsic muscles of the hand and some flexor muscles in the forearm. - It has no motor supply to the muscles of the **flexor compartment of the arm**.
Question 142: The blood supply to femoral head is mostly by?
- A. Lateral epiphyseal artery
- B. Medial epiphyseal artery
- C. Artery of ligamentum teres
- D. Profunda femoris (Correct Answer)
Explanation: ***Profunda femoris*** - The profunda femoris artery (deep femoral artery) gives rise to the **medial and lateral circumflex femoral arteries**, which are the primary blood supply to the femoral head in adults - Specifically, the **medial circumflex femoral artery** and its branches (lateral epiphyseal arteries and retinacular arteries) form an extracapsular arterial ring and penetrate the joint capsule to supply the femoral head - The profunda femoris is thus the main parent vessel responsible for femoral head blood supply *Lateral epiphyseal artery* - This artery is a branch of the **medial circumflex femoral artery**, which originates from the profunda femoris - While it directly supplies the femoral head and is the dominant terminal branch, it represents a more specific component of the arterial network rather than the main source vessel - It provides blood to the lateral and superior portions of the femoral head *Medial epiphyseal artery* - This artery is also a branch of the circumflex femoral arteries, which originate from the profunda femoris - It contributes to the blood supply but is less dominant than the lateral epiphyseal branches - Similar to lateral epiphyseal artery, it is part of the retinacular arterial system *Artery of ligamentum teres* - The **artery of the ligamentum teres** (foveal artery) is an inconsistent and often small vessel, typically a branch of the **obturator artery** or medial circumflex femoral artery - While it contributes to blood supply especially in children, its contribution is usually minor in adults and often insufficient to sustain the femoral head alone - It enters through the fovea capitis and its contribution diminishes with age
Question 143: Which of the following muscles is not in the pectoral region?
- A. Pectoralis major
- B. Infraspinatus (Correct Answer)
- C. Pectoralis minor
- D. Subclavius
Explanation: ***Infraspinatus*** - The **infraspinatus** muscle is located in the **posterior scapular region**, specifically on the posterior aspect of the scapula, filling the infraspinous fossa. - Its primary function is **external rotation** of the humerus, and it is a key component of the **rotator cuff**. *Pectoralis major* - The **pectoralis major** is a large, superficial muscle located in the **anterior chest wall**, forming the bulk of the chest. [1] - It plays a significant role in **adduction**, **flexion**, and **medial rotation** of the humerus. *Pectoralis minor* - The **pectoralis minor** is a smaller, triangular muscle situated beneath the pectoralis major in the **anterior thoracic wall**. [1] - Its functions include **stabilizing the scapula** by pulling it inferiorly and anteriorly, and assisting in forced inspiration. [1] *Subclavius* - The **subclavius** is a small, triangular muscle located inferior to the clavicle in the **pectoral region**. - Its primary role is to **depress and stabilize the clavicle**, protecting the underlying neurovascular structures.
Question 144: Which of the following statements about the mammary gland is false?
- A. Is a modified sweat gland
- B. Extends from 2nd to 6th rib vertically
- C. Supplied by internal mammary artery
- D. Nipple is supplied by 6th intercostal nerve (Correct Answer)
Explanation: ***Nipple is supplied by 6th intercostal nerve*** - The **nipple and areola** are primarily supplied by branches of the **4th intercostal nerve**. - The 6th intercostal nerve supplies the lower part of the breast and is not the primary innervation for the nipple. *Is a modified sweat gland* - The mammary gland, or breast, is indeed a **modified apocrine sweat gland**. - This embryological origin explains its glandular structure and function of milk production. *Extends from 2nd to 6th rib vertically* - The vertical extent of the mammary gland typically ranges from the **2nd to the 6th rib**. - This anatomical positioning is consistent with its location on the anterior thoracic wall. *Supplied by internal mammary artery* - The **internal mammary artery (internal thoracic artery)** is a major blood supply to the medial aspect of the breast [2]. - Other significant arteries include the lateral thoracic and thoracoacromial arteries for the lateral aspect. The mammary gland is embedded in subcutaneous fat, although fat is absent beneath the nipple and areola [1]. Mature resting breasts lie between the skin and the pectoralis major muscle, supported by Cooper's ligaments [3].
Biochemistry
1 questionsThe main function of Vitamin C in the body is
NEET-PG 2013 - Biochemistry NEET-PG Practice Questions and MCQs
Question 141: The main function of Vitamin C in the body is
- A. Cofactor for hydroxylation reactions in collagen synthesis (Correct Answer)
- B. Regulation of lipid synthesis
- C. Involvement as antioxidant
- D. Inhibition of cell growth
Explanation: ***Cofactor for hydroxylation reactions in collagen synthesis*** - Vitamin C (ascorbic acid) serves as an essential **cofactor** for **prolyl hydroxylase** and **lysyl hydroxylase** enzymes. - These enzymes catalyze the **hydroxylation of proline and lysine** residues in collagen, forming **hydroxyproline** and **hydroxylysine**. - This hydroxylation is crucial for the **stability and cross-linking** of collagen triple helix structure. - Deficiency leads to **scurvy**, characterized by defective collagen synthesis, bleeding gums, poor wound healing, and bone abnormalities. - This is the **primary and main function** of Vitamin C in the human body. *Involvement as antioxidant* - While Vitamin C does act as a **water-soluble antioxidant**, protecting cells from oxidative damage by free radicals, this is a **secondary function**. - It can donate electrons to neutralize reactive oxygen species and regenerate other antioxidants like Vitamin E. - This protective role is important but not the main function compared to its role in collagen synthesis. *Regulation of lipid synthesis* - Vitamin C is **not directly involved** in the primary pathways of lipid synthesis or metabolism. - It may play a minor role in **carnitine synthesis** (needed for fatty acid oxidation), but this is not a major function. - Other nutrients like B vitamins play more significant roles in lipid metabolism regulation. *Inhibition of cell growth* - Vitamin C does **not inhibit normal cell growth**; it is essential for cell health, differentiation, and tissue repair. - While high doses may have some anti-proliferative effects in certain cancer cell lines in vitro, this is not a physiological function in the healthy body.
Internal Medicine
3 questionsWhich of the following glands is NOT typically involved in Multiple Endocrine Neoplasia type II A (MEN II A)?
Autoimmune thyroiditis is associated with all except which of the following?
Which one of the following is the most common CNS tumor associated with type I neurofibromatosis?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 141: Which of the following glands is NOT typically involved in Multiple Endocrine Neoplasia type II A (MEN II A)?
- A. Pituitary gland (Correct Answer)
- B. Thyroid gland
- C. Parathyroid gland
- D. Adrenal gland
Explanation: ***Pituitary gland*** - The **pituitary gland** is not a characteristic component of **MEN II A**. It is, however, associated with **Multiple Endocrine Neoplasia type I (MEN I)**, which involves the 3 Ps: **pituitary**, **parathyroid**, and **pancreas** [1]. - **MEN IIA** classically involves **medullary thyroid carcinoma**, **pheochromocytoma**, and **parathyroid hyperplasia** [1]. *Thyroid gland* - The **thyroid gland** is centrally involved in MEN IIA, specifically through the development of **medullary thyroid carcinoma (MTC)**, a hallmark feature. - MTC arises from the parafollicular C cells of the thyroid and secretes **calcitonin**. *Parathyroid gland* - The **parathyroid gland** is often involved in MEN IIA, typically presenting as **parathyroid hyperplasia** or adenoma, leading to **primary hyperparathyroidism**. - This typically results in elevated **parathyroid hormone** levels and **hypercalcemia**. *Adrenal gland* - The **adrenal gland** is a key player in MEN IIA due to the occurrence of **pheochromocytoma**, a tumor of the adrenal medulla. - Pheochromocytomas can be bilateral and secrete **catecholamines**, leading to hypertension and other symptoms.
Question 142: Autoimmune thyroiditis is associated with all except which of the following?
- A. DM
- B. Myasthenia gravis
- C. SLE
- D. Psoriasis (Correct Answer)
Explanation: ***Psoriasis*** - Psoriasis is generally not associated with **autoimmune thyroiditis**, which is more commonly linked to other autoimmune disorders [1]. - Autoimmune thyroiditis does not typically result in the **skin changes** seen in psoriasis, distinguishing them clinically. *Sly* - Sly syndrome, while a genetic disorder, is not directly connected to **autoimmune thyroiditis**. - Conditions like Sly syndrome are metabolic and do not involve the autoimmune pathways typically seen in thyroiditis. *Myasthenia gravis* - Myasthenia gravis is an **autoimmune neuromuscular disorder** that can occur concurrently with thyroid diseases, particularly **thyroiditis** [1]. - Both conditions arise from **autoimmune processes**, making their association plausible [1]. *DM* - Diabetes Mellitus (DM), particularly Type 1, is often linked with other autoimmune diseases, including **autoimmune thyroiditis** [2]. - They share a common **autoimmune pathway**, making them more likely to co-occur than psoriasis [2].
Question 143: Which one of the following is the most common CNS tumor associated with type I neurofibromatosis?
- A. Optic nerve glioma (Correct Answer)
- B. Meningioma
- C. Acoustic schwannoma
- D. Low grade astrocytoma
Explanation: ***Optic nerve glioma*** - **Optic nerve gliomas** are the most frequently encountered central nervous system tumors in patients with **Type 1 neurofibromatosis (NF1)**, occurring in about 15% of individuals. - They are typically low-grade **astrocytomas** and can cause vision loss and proptosis depending on their size and location. *Meningioma* - While more common in **Type 2 neurofibromatosis (NF2)**, meningiomas can occur in NF1, but are not the most common CNS tumor. - Meningiomas are tumors that arise from the **meninges**, the membranes surrounding the brain and spinal cord. *Acoustic schwannoma* - **Bilateral acoustic schwannomas (vestibular schwannomas)** are the hallmark feature of **Type 2 neurofibromatosis (NF2)**, not NF1 [1]. - These tumors arise from the Schwann cells of the **vestibulocochlear nerve** and can cause hearing loss and balance issues [1]. *Low grade astrocytoma* - While optic nerve gliomas are a type of low-grade astrocytoma, this option is too general; **optic nerve glioma** is the specific and most common presentation in NF1. - Other forms of low-grade astrocytomas can occur in NF1 but are not as universally characteristic as optic nerve gliomas.
Pathology
1 questionsWhich of the following is not a germ cell tumor?
NEET-PG 2013 - Pathology NEET-PG Practice Questions and MCQs
Question 141: Which of the following is not a germ cell tumor?
- A. Embryonal carcinoma
- B. Endodermal sinus
- C. Seminoma
- D. Leydig cell tumor (Correct Answer)
Explanation: ***Leydig cell tumor*** - Leydig cell tumors are classified as **sex-cord stromal tumors**, not germ cell tumors [1]. - These tumors are derived from **Leydig cells** which produce androgens, affecting the endocrine function rather than germ cell lineage [1]. *Endodermal sinus* - Endodermal sinus tumors, or **yolk sac tumors**, are indeed germ cell tumors characterized by **alpha-fetoprotein (AFP)** production [2]. - They typically arise in the testis or ovaries and are known for rapid growth and aggressiveness. *Embryonal carcinoma* - Embryonal carcinoma is a type of **germ cell tumor** commonly associated with elevated levels of **beta-hCG** [2]. - It primarily affects the testes in males and can occur in the ovaries, and it is known for its aggressive behavior. *Seminoma* - Seminomas are classic examples of **germ cell tumors**, noted for their sensitivity to radiation and chemotherapy [3]. - They usually present with **increased beta-hCG** levels and can coexist with non-seminomatous germ cell tumors [3]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 510-514. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 979-980. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 980-982.
Pharmacology
1 questionsWhich of the following drugs is used for Smoking Cessation?
NEET-PG 2013 - Pharmacology NEET-PG Practice Questions and MCQs
Question 141: Which of the following drugs is used for Smoking Cessation?
- A. Bupropion (Correct Answer)
- B. Methadone
- C. Buprenorphine
- D. Naltrexone
Explanation: ***Bupropion*** - **Bupropion** is an antidepressant that is also approved as a smoking cessation aid. It works by inhibiting the reuptake of **dopamine** and **norepinephrine**, which can help reduce nicotine cravings and withdrawal symptoms. - It is often prescribed as a first-line pharmacotherapy for smoking cessation, with a typical treatment duration of 7-12 weeks. *Buprenorphine* - **Buprenorphine** is a partial opioid agonist primarily used to treat opioid addiction. It is not indicated for smoking cessation. - While it can help manage withdrawal symptoms from opioids, it has no direct mechanism of action that would reduce nicotine dependence or cravings. *Methadone* - **Methadone** is a full opioid agonist primarily used for the treatment of opioid use disorder (OUD) and chronic pain management. It is not used for smoking cessation. - Its mechanism involves binding to opioid receptors to prevent withdrawal symptoms and reduce cravings for other opioids. *Naltrexone* - **Naltrexone** is an opioid antagonist used primarily for the treatment of alcohol dependence and opioid use disorder. It is not indicated for smoking cessation. - It blocks the effects of opioids and reduces alcohol cravings, but does not affect nicotine pathways or dependence.