NEET-PG 2012 Practice Questions

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: Cricoid cartilage lies at which vertebral level?

C6. **C6** - The **cricoid cartilage** is an important anatomical landmark, as it signifies the transition from the **laryngopharynx** to the **esophagus** and the start of the **trachea**. - Its location at **C6 vertebral level** is significant for procedures like tracheostomy and in identifying the narrowest part of the adult airway. *C3* - The C3 vertebral level is typically associated with the **hyoid bone**, which is superior to the cricoid cartilage. - The **epiglottis** and the superior aspect of the larynx are more commonly found at C3-C4. *T1* - The T1 vertebral level is in the **thoracic spine**, well below the neck, and is associated with the **apex of the lung** and the **first rib**. - The airway structures at this level are primarily the **trachea** as it enters the thorax. *T4* - The T4 vertebral level is significant as it marks the approximate location of the **carina**, where the trachea bifurcates into the main bronchi. - This level is much lower than the larynx and cricoid cartilage.

Q: Which of the following is a traction epiphysis ?

Coracoid process of scapula. ***Coracoid process of scapula*** - A **traction epiphysis** (also called atavistic epiphysis) serves as an attachment site for muscles and tendons, transferring muscle force to the bone without bearing significant weight or forming articular surfaces. - The **coracoid process** is a classic example, anchoring the **pectoralis minor, coracobrachialis, and short head of biceps brachii**, as well as important ligaments (coracoclavicular and coracoacromial). - It develops from a separate ossification center purely for muscle and ligament attachment, not for articulation or weight-bearing. *Tibial condyles* - The **tibial condyles** are **pressure epiphyses** (articular epiphyses) that form the superior articular surface of the tibia. - They articulate with the femoral condyles to form the knee joint and bear significant weight during standing and movement. - Their primary function is joint formation and contribution to longitudinal bone growth. *Trochanter of femur* - The **greater and lesser trochanters** are large bony prominences that serve as muscle attachment sites, but they are better classified as **apophyses** rather than true traction epiphyses. - An **apophysis** is a secondary ossification center that does not contribute to longitudinal bone growth and serves primarily for muscle attachment. - While functionally similar to traction epiphyses, the term "traction epiphysis" is more specifically applied to structures like the coracoid process, tibial tuberosity, and calcaneal tuberosity. *Head of femur* - The **head of femur** is a classic **pressure epiphysis** that articulates with the acetabulum to form the hip joint. - It bears significant body weight and contributes to the longitudinal growth of the femur. - Its primary functions are joint formation and weight transmission, not muscle attachment.

Q: What anatomical structures are involved in the closure of the fossa ovalis?

Septum primum + Septum secundum. The septum primum acts as a valve, closing against the septum secundum postnatally due to changes in atrial pressure. This fusion effectively closes the foramen ovale, leading to the formation of the fossa ovalis. The endocardial cushions are important for the formation of the atrial and ventricular septa, as well as the AV valves, but not directly for the closure of the fossa ovalis. The septum primum is directly involved, but its apposition with the endocardial cushions doesn't close the foramen ovale. While both structures contribute to heart development, their direct interaction is not responsible for the closure of the fossa ovalis. The septum secundum forms the muscular rim of the fossa ovalis, and the endocardial cushions are critical for atrial septation, but not the final closure here. This option is incorrect because the specific combination of septum primum and septum secundum is indeed responsible for the closure of the fossa ovalis.

Q: Renal papilla opens into -

Minor calyx. ***Minor calyx*** - The **renal papilla** is the apex of the renal pyramid, which drains urine directly into a **minor calyx**. - Minor calyces then merge to form major calyces, eventually leading to the renal pelvis. *Cortex* - The **renal cortex** is the outer layer of the kidney, containing glomeruli and convoluted tubules, and does not directly receive urine from the papilla. - Urine is primarily formed and filtered in the cortex and then flows into the medulla. *Pyramid* - A **renal pyramid** is a conical structure within the renal medulla, and the renal papilla is its tip, but it doesn't open *into* the pyramid itself. - Instead, the pyramid *contains* the structures that contribute to the papilla. *Major calyx* - A **major calyx** is formed by the convergence of several minor calyces. - The renal papilla drains into the minor calyx, which then, in turn, drains into the major calyx.

Q: Azygos vein drains into:

Superior vena cava. Wait, what? Azygos vein drains into: ***Superior vena cava*** - The **azygos vein** ascends along the right side of the vertebral column and typically arches over the root of the right lung before draining into the **superior vena cava (SVC)**. - This anatomical arrangement allows the azygos system to collect venous blood from the posterior thoracic and abdominal walls, as well as the bronchi and esophagus, ultimately returning it to the systemic circulation via the SVC [1]. *Left brachiocephalic vein* - The **left brachiocephalic vein** drains blood from the upper left limb and left side of the head and neck. - It merges with the right brachiocephalic vein to form the SVC; the azygos vein does not directly drain into it. *Inferior vena cava* - The **inferior vena cava (IVC)** collects deoxygenated blood from the lower body. - The azygos system primarily drains structures above the diaphragm, distinct from the IVC's drainage area. *Right brachiocephalic vein* - The **right brachiocephalic vein** drains blood from the upper right limb and right side of the head and neck. - While it contributes to the formation of the SVC, the azygos vein's direct connection is to the SVC itself, not the right brachiocephalic vein.

Q: All are derived from ectoderm except for which of the following?

Adrenal cortex. ***Adrenal cortex*** - The adrenal cortex is derived from the **intermediate mesoderm**, specifically from the cells lining the posterior abdominal wall. The cells migrate to develop into the adrenal cortex. - It produces various steroid hormones, including **aldosterone**, **cortisol**, and **androgens**, which regulate diverse bodily functions. *Lens of the eye* - The lens of the eye is derived from the **surface ectoderm**. It forms from an invagination of the surface ectoderm called the lens placode. - Its primary function is to **focus light** onto the retina. *Hair follicles* - Hair follicles develop from the **surface ectoderm** [1]; they are invaginations of the epidermis that extend into the dermis. - They produce hair, which provides **insulation** and **protection** [1]. *Nails* - Nails are also derivatives of the **surface ectoderm**, forming thickened plates on the dorsal surface of the distal phalanges. - They provide **protection** to the fingertips and aid in grasping objects.

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.

Question 1

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 2

Cricoid cartilage lies at which vertebral level?

Accepted Answer

C6

Answer

C3

Answer

T1

Answer

T4

Question 3

Which of the following is a traction epiphysis ?

Accepted Answer

Coracoid process of scapula

Answer

Tibial condyles

Answer

Head of femur

Answer

Trochanter of femur

Question 4

What anatomical structures are involved in the closure of the fossa ovalis?

Accepted Answer

Septum primum + Septum secundum

Answer

Septum primum + Endocardial cushion

Answer

Endocardial cushions + Septum secundum

Answer

None of the options

Question 5

Renal papilla opens into -

Accepted Answer

Minor calyx

Answer

Cortex

Answer

Pyramid

Answer

Major calyx

Question 6

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 7

Azygos vein drains into:

Accepted Answer

Superior vena cava

Answer

Left brachiocephalic vein

Answer

Inferior vena cava

Answer

Right brachiocephalic vein

Question 8

All are derived from ectoderm except for which of the following?

Accepted Answer

Adrenal cortex

Answer

Hair follicles

Answer

Nails

Answer

Lens of the eye

Question 9

Nutrient artery runs ?

Accepted Answer

Away from epiphysis

Answer

Towards metaphysis

Answer

None of the options

Answer

Away from metaphysis

Question 10

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

NEET-PG 2012

Anatomy

Orthopaedics