NEET-PG 2012 Practice Questions

Q: Blastocyst makes contact with endometrium on ?

5 - 7 days. ***5-7 days*** - The **blastocyst makes initial contact** (apposition) with the **endometrium** around **day 5-6 after fertilization**. - **Implantation**, which includes adhesion and invasion, typically begins around day 6 and is complete by day 10. - This timeframe allows the blastocyst to travel from the fallopian tube to the uterus and for the uterine lining to be optimally prepared. *< 3 days* - Within the first few days after fertilization, the zygote is still undergoing **cleavage** and development into a **morula**, then a young blastocyst, while traveling down the fallopian tube. - It has not yet reached the uterus or developed sufficiently to interact with the endometrium. *8-11 days* - By 8-11 days, the process of implantation is usually **well underway or completed**, with the blastocyst already invading the endometrial wall. - Initial contact and attachment occur prior to this period. *15-16 days* - This timeframe is well beyond the typical window for initial blastocyst contact and implantation. - By 15-16 days post-fertilization, the embryo would be undergoing **gastrulation** and early organogenesis, assuming successful implantation.

Q: Which is derived from Wolffian duct?

Appendix of epididymis. The **appendix of the epididymis** is a vestigial structure directly derived from the mesonephric (Wolffian) duct in males. It is an embryological remnant of this duct, located at the head of the epididymis. *Appendix of the testis* - The **appendix of the testis** (hydatid of Morgagni) is a remnant of the paramesonephric (Müllerian) duct, not the Wolffian duct. - It is usually found on the upper pole of the testis, typically near the epididymis. *Uterine structure* - **Uterine structures** (uterus, fallopian tubes, and upper vagina) are derived from the paramesonephric (Müllerian) ducts in females [1]. - The Wolffian ducts largely regress in females due to the absence of testosterone. *Hydatid of Morgagni* - The term **hydatid of Morgagni** can refer to the appendix of the testis (Müllerian duct remnant) or, less commonly, to the appendix of the epididymis (Wolffian duct remnant). - However, in common clinical and anatomical usage, it almost exclusively refers to the **appendix of the testis**, which is a Müllerian duct derivative.

Q: In walking, gravity tends to tilt pelvis and trunk to the unsupported side, the major factor in preventing this unwanted movement is?

Gluteus medius and minimus. ***Gluteus medius and minimus*** - The **gluteus medius** and **gluteus minimus** are essential **abductors** of the hip, primarily responsible for stabilizing the pelvis during the **single-limb support phase of gait**. - When one leg is lifted during walking, these muscles on the **stance leg side** contract to prevent the pelvis from tilting downwards on the unsupported swing leg side. *Adductor muscles* - **Adductor muscles** (adductor longus, brevis, magnus, pectineus, gracilis) primarily function to bring the thigh toward the midline of the body. - While they play a role in gait stability, their main action is not to prevent the lateral pelvic tilt described. *Quadriceps* - The quadriceps femoris group (rectus femoris, vastus lateralis, medialis, intermedius) are powerful **extensors of the knee**. - They are crucial for weight acceptance and propulsion during walking but do not directly prevent lateral pelvic tilt [1]. *Gluteus maximus* - The **gluteus maximus** is the largest and most powerful muscle of the hip, primarily responsible for **hip extension** and **external rotation**. - It is crucial for activities like climbing stairs or running, but its main role in normal walking is not to prevent lateral pelvic tilt; that function is more specific to the gluteus medius and minimus.

Q: Which of the following statements provides the MOST COMPLETE description of sclerotome function during vertebral development?

The sclerotome surrounds the notochord and the neural tube during development.. ***The sclerotome surrounds the notochord and the neural tube during development.*** - The **sclerotome** is the part of the somite that differentiates into mesenchymal cells and migrates to surround both the developing **notochord** (which gives rise to the nucleus pulposus) and the **neural tube** (which forms the spinal cord). - This encirclement is crucial for the formation of the **vertebral column**, providing protection and a structural framework. *The notochord forms the nucleus pulposus.* - While true that the **notochord** contributes to the **nucleus pulposus**, this statement describes the fate of the notochord itself, not the function of the sclerotome. - The question asks for the function of the sclerotome, and this option only details one specific derivative. *The sclerotome contributes to the formation of vertebral bodies.* - This statement is partially true, as the **sclerotome** does indeed form the **vertebral bodies**, arches, and intervertebral discs. - However, it is not the *most complete* description of its function during development, as it omits the crucial aspect of surrounding the neural tube. *The sclerotome surrounds the notochord.* - This statement is correct but **incomplete** as it only mentions the notochord. - The **sclerotome** also surrounds the **neural tube**, which is a vital part of its developmental role in forming the vertebral canal.

Q: Haploid number of chromosomes is first seen in?

Secondary spermatocyte. ***Secondary spermatocyte*** - A secondary spermatocyte is formed after **meiosis I**, where the homologous chromosomes are separated, resulting in a cell with a **haploid number of chromosomes (n)**, although each chromosome still consists of two sister chromatids. - This is the **first stage** where haploidy is achieved in spermatogenesis. - These cells are transient and quickly undergo meiosis II to form spermatids. *Spermatogonia* - Spermatogonia are **diploid (2n)** germline stem cells that undergo mitosis to produce more spermatogonia or differentiate into primary spermatocytes. - They contain the full complement of chromosomes found in somatic cells. *Primary spermatocytes* - Primary spermatocytes are also **diploid (2n)** cells that enter meiosis I. - Before meiosis I, DNA replication occurs, so each chromosome consists of two sister chromatids, but the cell still maintains a diploid chromosome number. *Spermatids* - Spermatids are formed after **meiosis II** from secondary spermatocytes and are also **haploid (n)**. - However, secondary spermatocytes become haploid **earlier** in the process, immediately following the reductional division of meiosis I.

Q: Which statement accurately describes a characteristic of synovial joints?

Hyaline cartilage covers the articular surfaces of synovial joints.. ***Hyaline cartilage covers the articular surfaces of synovial joints.*** - The articular surfaces of bones within a **synovial joint** are covered by a thin layer of **hyaline cartilage**, providing a smooth, low-friction surface for movement [1]. - This **articular cartilage** absorbs shock and protects the underlying bone from wear and tear [1]. - This is a **universal structural characteristic** of all synovial joints, making it the most accurate answer. *The metacarpo-phalangeal joint is a condyloid joint.* - While this statement is factually true (MCP joints are indeed **condyloid/ellipsoid joints** allowing movement in two planes), it describes a **specific type** of synovial joint, not a general characteristic of all synovial joints. - The question asks for a characteristic that describes synovial joints as a category, not an example of one specific joint classification. - This makes it incorrect as the best answer to this question. *Cartilage can sometimes divide the joint into two cavities.* - This statement refers to an **articular disc** or **meniscus**, which is a fibrocartilaginous structure that can partially or completely divide a synovial joint cavity. - This feature is present in **some** synovial joints (like the knee or temporomandibular joint) but is **not universal**. - Since it's not a characteristic of all synovial joints, it's not the best answer. *Stability is inversely proportional to mobility in synovial joints.* - Generally, there is an **inverse relationship** between **stability** and **mobility** in joints; joints designed for great mobility (e.g., shoulder) tend to be less stable, and vice-versa (e.g., hip). - However, this describes a **functional principle** or trade-off rather than a **structural characteristic** that defines synovial joints. - While true, it's not the defining characteristic being asked for in this question.

Q: Which muscle stabilizes the clavicle during movement of the shoulder?

Subclavius. ***Subclavius*** - The **subclavius muscle** originates from the first rib and inserts into the inferior surface of the clavicle, acting to **depress the clavicle** and prevent its displacement, thus enhancing shoulder stability during movement. - It plays a crucial role in protecting the underlying **neurovascular structures** (brachial plexus and subclavian vessels) from external trauma to the shoulder. *Pectoralis major* - This large, fan-shaped muscle primarily functions in **adduction, medial rotation, and flexion of the humerus** at the shoulder joint [1]. - It does not directly stabilize the clavicle but rather acts on the arm. *Latissimus dorsi* - The **latissimus dorsi** is a broad muscle of the back responsible for **extension, adduction, and internal rotation of the humerus** [1]. - Its actions are mainly on the humerus and it does not directly stabilize the clavicle. *Serratus anterior* - The **serratus anterior** muscle primarily **protracts and rotates the scapula**, keeping it pressed against the thoracic wall. - While it's essential for **scapular stability** and overhead arm movements, it does not directly stabilize the clavicle.

Q: Nutrient artery runs ?

Away from epiphysis. ***Away from epiphysis*** - The **nutrient artery** runs away from the **dominant (faster-growing) epiphysis** towards the non-dominant end of the bone. - This follows the classic anatomical rule: **"To the elbow, from the knee"** - nutrient arteries point towards the elbow in upper limb bones and away from the knee in lower limb bones. - The **nutrient foramen** is directed obliquely away from the more actively growing end, established during bone development. - Examples: In the humerus, it runs towards the elbow (away from proximal epiphysis); in the femur, it runs away from the knee (away from distal epiphysis). *Towards metaphysis* - While the artery does course towards the metaphyseal region of the slower-growing end, this option is less anatomically precise. - The standard teaching emphasizes the relationship with the **dominant epiphysis** rather than the metaphysis. *Away from metaphysis* - This is **incorrect** - the nutrient artery actually runs **towards** the metaphysis of the non-dominant end. - It runs **away from** the dominant epiphysis, not away from the metaphysis. *None of the options* - This is incorrect as **"Away from epiphysis"** correctly describes the direction of the nutrient artery relative to the dominant growing end.

Q: Which of the following conditions can cause locking of the knee joint?

Loose body in knee joint. ***Loose body in knee joint*** - A **loose body** (e.g., a fragment of cartilage or bone) can get trapped between the articular surfaces of the knee joint, mechanically obstructing its movement and causing sudden, painful **locking**. - This mechanical impingement prevents full extension or flexion of the knee until the loose body shifts, leading to episodic locking symptoms. *Osgood Schlatter* - This condition involves inflammation and potential avulsion of the **tibial tuberosity** where the patellar tendon inserts. - It primarily causes pain and swelling below the kneecap, especially during physical activity, but does not typically result in true mechanical locking of the joint. *Tuberculosis of knee* - **Tuberculosis of the knee joint** is an infectious arthritis that causes chronic pain, swelling, and gradual destruction of articular cartilage and bone. - While it can lead to pain and limited range of motion, it usually does not present with the sudden, intermittent mechanical locking characteristic of a loose body. *a and b both* - Neither **Osgood Schlatter** nor **Tuberculosis of the knee** typically cause the characteristic mechanical locking sensation described for a loose body in the joint. - Each of these conditions has distinct pathophysiological mechanisms and clinical presentations that do not involve a physical obstruction causing locking.

Q: IVC filter is used in the following situations except -

As primary treatment for acute DVT. ***As primary treatment for acute DVT*** - The **primary treatment** for **acute deep vein thrombosis (DVT)** is **anticoagulation therapy** (heparin, warfarin, or DOACs) to prevent clot propagation and embolization. - An **IVC filter** is **NOT primary therapy**—it is reserved for specific situations and does not treat the underlying thrombosis. - **Indications for IVC filter include:** - Absolute **contraindication to anticoagulation** (active bleeding, recent hemorrhagic stroke) - **Recurrent PE despite adequate anticoagulation** - Complications from anticoagulation therapy - Therefore, using IVC filter as primary treatment for acute DVT is **incorrect and not indicated**. *Negligible size of emboli* - While IVC filters trap **large emboli**, the concept of "negligible size emboli" is not a standard clinical consideration for filter placement. - IVC filters are indicated based on **risk of PE** and **contraindications to anticoagulation**, not based on emboli size assessment. *To reduce symptoms* - **IVC filters** do not reduce symptoms of DVT such as pain, swelling, or discomfort. - They function as a **mechanical barrier** to prevent emboli from reaching pulmonary circulation. - Symptom management requires anticoagulation, compression therapy, and leg elevation. *To prevent progress of native blood vessel disease* - IVC filters do not influence progression of underlying **vascular disease** such as atherosclerosis or chronic venous insufficiency. - Their sole function is **mechanical prevention of PE**, not disease modification.

Question 1

Blastocyst makes contact with endometrium on ?

Accepted Answer

5 - 7 days

Answer

< 3 days

Answer

8 - 11 days

Answer

15-16 days

Question 2

Which is derived from Wolffian duct?

Accepted Answer

Appendix of epididymis

Answer

Appendix of the testis

Answer

Uterine structure

Answer

Hydatid of Morgagni

Question 3

In walking, gravity tends to tilt pelvis and trunk to the unsupported side, the major factor in preventing this unwanted movement is?

Accepted Answer

Gluteus medius and minimus

Answer

Adductor muscles

Answer

Quadriceps

Answer

Gluteus maximus

Question 4

Which of the following statements provides the MOST COMPLETE description of sclerotome function during vertebral development?

Accepted Answer

The sclerotome surrounds the notochord and the neural tube during development.

Answer

The notochord forms the nucleus pulposus.

Answer

The sclerotome contributes to the formation of vertebral bodies.

Answer

The sclerotome surrounds the notochord.

Question 5

Haploid number of chromosomes is first seen in?

Accepted Answer

Secondary spermatocyte

Answer

Spermatogonia

Answer

Primary spermatocytes

Answer

Spermatids

Question 6

Which statement accurately describes a characteristic of synovial joints?

Accepted Answer

Hyaline cartilage covers the articular surfaces of synovial joints.

Answer

The metacarpo-phalangeal joint is a condyloid joint.

Answer

Cartilage can sometimes divide the joint into two cavities.

Answer

Stability is inversely proportional to mobility in synovial joints.

Question 7

Which muscle stabilizes the clavicle during movement of the shoulder?

Accepted Answer

Subclavius

Answer

Pectoralis major

Answer

Latissimus dorsi

Answer

Serratus anterior

Question 8

Nutrient artery runs ?

Accepted Answer

Away from epiphysis

Answer

Towards metaphysis

Answer

None of the options

Answer

Away from metaphysis

Question 9

Which of the following conditions can cause locking of the knee joint?

Accepted Answer

Loose body in knee joint

Answer

Osgood Schlatter

Answer

Tuberculosis of knee

Answer

a and b both

Question 10

IVC filter is used in the following situations except -

Accepted Answer

As primary treatment for acute DVT

Answer

To reduce symptoms

Answer

Negligible size of emboli

Answer

To prevent progress of native blood vessel disease

NEET-PG 2012

Anatomy

Orthopaedics

Surgery