Anatomy
8 questionsWhat is the preferred site for intramuscular injection in the gluteus muscle?
Sympathetic supply to the heart arises from which of the following spinal segments?
Which of the following is not a boundary of the triangle of auscultation?
Which nerve primarily supplies the cervical esophagus?
What is the anatomical significance of the Rhinion in relation to the osseocartilaginous junction?
Ophthalmic artery is a branch of:
Which of the following is not the part of ethmoid bone?
Primary and secondary palates are divided by
NEET-PG 2012 - Anatomy NEET-PG Practice Questions and MCQs
Question 371: What is the preferred site for intramuscular injection in the gluteus muscle?
- A. Inferolateral
- B. Superolateral (Correct Answer)
- C. Superomedial
- D. Inferomedial
Explanation: ***Superolateral*** - This quadrant is preferred because it avoids the **sciatic nerve** and major **blood vessels**, minimizing the risk of injury. - The muscle mass in this region, primarily the **gluteus medius**, is sufficient for medication absorption. *Inferomedial* - This area carries a high risk of damaging the **sciatic nerve**, which runs through the lower, medial part of the gluteus. - Injecting here can also hit major **blood vessels**, leading to bleeding or hematoma. *Superomedial* - While somewhat safer than the inferomedial quadrant, this area is still closer to the **sciatic nerve** exit point and major vessels compared to the superolateral region. - The muscle bulk is also less prominent here compared to the superolateral aspect. *Inferolateral* - This quadrant is still in the vicinity of the **sciatic nerve** and major blood vessels, making it riskier than the superolateral site. - There is less muscle mass here compared to the superior quadrants, which can lead to improper drug absorption.
Question 372: Sympathetic supply to the heart arises from which of the following spinal segments?
- A. T1 to T5 (Correct Answer)
- B. T2 to T6
- C. T3 to T7
- D. T4 to T8
Explanation: The preganglionic sympathetic fibers that innervate the heart originate from the lateral horns of the thoracic spinal segments T1 to T5. These fibers synapse in the cervical and upper thoracic sympathetic ganglia, from which postganglionic fibers extend to the heart. While there is some overlap, the primary and most significant sympathetic innervation to the heart stems predominantly from T1 to T5, making T2 to T6 a less precise answer. Including T6 would extend past the typical primary cardiac sympathetic innervation, which largely concludes at T5. This range is too caudal and largely beyond the principal segments providing sympathetic innervation to the heart. Segments T6-T8 are more involved in sympathetic supply to abdominal organs and other structures rather than direct cardiac control.
Question 373: Which of the following is not a boundary of the triangle of auscultation?
- A. Trapezius
- B. Scapula
- C. Rhomboid major (Correct Answer)
- D. Latissimus dorsi
Explanation: ***Rhomboid major*** - The **rhomboid major** muscle forms the **floor** of the triangle of auscultation, not one of its boundaries. - Its function is to **retract** and **rotate** the scapula, anchoring it to the thoracic wall. *Trapezius* - The **trapezius** muscle forms the **superior** and **medial** boundary of the triangle of auscultation. - It defines the upper limit of this anatomical space on the back. *Scapula* - The **medial border of the scapula** forms the **lateral** boundary of the triangle of auscultation. - This bony landmark helps to delineate the outer edge of the triangle. *Latissimus dorsi* - The **latissimus dorsi** muscle forms the **inferior** boundary of the triangle of auscultation. - It defines the lower limit of this region, allowing for better sound transmission to the thoracic cavity.
Question 374: Which nerve primarily supplies the cervical esophagus?
- A. Vagus (Correct Answer)
- B. Left recurrent laryngeal nerve
- C. Right recurrent laryngeal nerve
- D. Phrenic nerve
Explanation: ***Vagus*** - The **vagus nerve** (cranial nerve X) provides parasympathetic innervation to the entire esophagus, including the cervical portion, through its branches. - For the **cervical esophagus** specifically, the vagus nerve supplies it via the **recurrent laryngeal nerve branches**, which provide motor innervation to the striated muscle in this region. - The vagus is considered the primary nerve because the recurrent laryngeal nerves are its direct branches, and the vagus coordinates overall esophageal function throughout its length. *Left recurrent laryngeal nerve* - The **left recurrent laryngeal nerve** is a branch of the vagus nerve that provides motor innervation to both the intrinsic muscles of the **larynx** and the **cervical esophagus**. - While it does directly supply the cervical esophagus with motor fibers, it is anatomically a branch of the vagus nerve rather than an independent primary supply. - In this context, the parent nerve (vagus) is considered the primary supply. *Right recurrent laryngeal nerve* - The **right recurrent laryngeal nerve** is also a branch of the vagus nerve that supplies both the laryngeal muscles and contributes to **cervical esophageal innervation**. - Like the left recurrent laryngeal nerve, it is a branch rather than the primary nerve source. - Both recurrent laryngeal nerves work as vagal branches to innervate the cervical esophagus. *Phrenic nerve* - The **phrenic nerve** (arising from C3-C5) primarily innervates the **diaphragm**, controlling respiration. - It does not supply the cervical esophagus and has no role in esophageal motility.
Question 375: What is the anatomical significance of the Rhinion in relation to the osseocartilaginous junction?
- A. Nasion
- B. Rhinion (Correct Answer)
- C. Radix
- D. Columella
Explanation: ***Correct Answer: Rhinion*** - The **rhinion** is the **most prominent anterior point of the nasal bone**, often palpable as a slight bump or angulation on the dorsum of the nose. - It marks the anatomical location of the **osseocartilaginous junction** of the nasal dorsum, where the bony nasal framework transitions to the cartilaginous framework. - This is the key anatomical landmark that defines the transition from bone to cartilage in the external nose. *Incorrect: Nasion* - The **nasion** is located at the **root of the nose**, specifically at the most anterior and superior point of the nasofrontal suture. - It is a bony landmark and does not directly relate to the osseocartilaginous junction of the nasal dorsum. *Incorrect: Radix* - The **radix** (or nasal root) refers to the **uppermost part of the nose**, corresponding to the nasion. - It defines the point where the nose begins to project from the forehead and is a bony landmark, not directly related to the osseocartilaginous junction. *Incorrect: Columella* - The **columella** is the **fleshy, narrow strip of tissue that separates the nostrils**. - It forms the inferior segment of the nasal septum and is composed of skin, soft tissue, and the medial crura of the alar cartilages, thus having no direct relation to the osseocartilaginous junction of the nasal dorsum.
Question 376: Ophthalmic artery is a branch of:
- A. Cavernous part of ICA
- B. Cerebral part of ICA (Correct Answer)
- C. MCA
- D. Facial artery
Explanation: ***Cerebral part of ICA*** - The **ophthalmic artery** is typically the first major branch off the **internal carotid artery (ICA)** once it exits the cavernous sinus and enters the cranial cavity. - This segment of the ICA is also known as the supraclinoid or **cerebral part**, underscoring its proximity to the brain. *Cavernous part of ICA* - The **cavernous part of the ICA** is located within the cavernous sinus and typically gives off smaller branches such as the **meningohypophyseal trunk** and the **inferolateral trunk**, which supply structures within and around the sinus. - The ophthalmic artery emerges after the ICA exits the cavernous sinus, not from within it. *MCA* - The **middle cerebral artery (MCA)** is a major terminal branch of the internal carotid artery, supplying large parts of the cerebrum. - It does not give rise to the ophthalmic artery, which branches off the ICA before the ICA bifurcates into the MCA and anterior cerebral artery. *Facial artery* - The **facial artery** is a branch of the **external carotid artery**, supplying structures of the face. - The ophthalmic artery is a primary supply to the orbit and is derived from the internal carotid artery, a completely separate vascular system.
Question 377: Which of the following is not the part of ethmoid bone?
- A. Agger nasi
- B. Crista galli
- C. Uncinate process
- D. Inferior turbinate (Correct Answer)
Explanation: ***Inferior turbinate*** - The **inferior turbinate** (or inferior nasal concha) is a separate paired facial bone, distinct from the ethmoid bone. - It articulates with the maxilla, lacrimal, palatine, and ethmoid bones but is not a component of the ethmoid. *Agger nasi* - The **agger nasi** is an anatomical variant, an anterior expansion of the ethmoid air cells, and is thus functionally part of the ethmoid complex. - While not a distinct bone, it is an **ethmoid cell** that can be found in the anterior aspect of the middle meatus. *Crista galli* - The **crista galli** is a prominent, upward projection from the cribriform plate of the ethmoid bone, serving as an attachment point for the falx cerebri. - It is an integral and easily recognizable part of the **ethmoid bone**. *Uncinate process* - The **uncinate process** is a sickle-shaped bony projection that arises from the inferior aspect of the ethmoid bone. - It forms the anterior boundary of the **hiatus semilunaris** and is crucial for the drainage of the frontal and maxillary sinuses.
Question 378: Primary and secondary palates are divided by
- A. Greater palatine foramen
- B. Canine teeth
- C. Alveolar arch
- D. Incisive foramen (Correct Answer)
Explanation: ***Incisive foramen*** - The **incisive foramen** is an anatomical landmark located just posterior to the central incisors, and it marks the boundary between the developmentally distinct primary and secondary palates. - The **primary palate** develops from the median palatine process, while the **secondary palate** develops from the palatal shelves of the maxillary prominences [1]. *Greater palatine foramen* - The **greater palatine foramen** is located near the posterior border of the hard palate, transmitting the greater palatine nerve and vessels. - It lies within the **secondary palate** and does not delineate the boundary between the primary and secondary palatal structures. *Canine teeth* - The **canine teeth** are part of the dental arch and play a role in mastication. - While located in the anterior part of the oral cavity, they are not a developmental or anatomical boundary marker for palatal divisions [1]. *Alveolar arch* - The **alveolar arch** is the bone that supports the teeth, forming the curved ridge of the maxilla and mandible [1]. - It is distinct from the palate and does not serve as a divider between the primary and secondary palatal components.
Anesthesiology
1 questionsWhich of the following is true about coeliac plexus block?
NEET-PG 2012 - Anesthesiology NEET-PG Practice Questions and MCQs
Question 371: Which of the following is true about coeliac plexus block?
- A. Usually done unilaterally
- B. Most common side effects include diarrhea and hypotension (Correct Answer)
- C. Located retroperitoneally at the level of L3
- D. Useful for painful conditions of the lower abdomen
Explanation: ***Most common side effects include diarrhea and hypotension*** - A coeliac plexus block interrupts **sympathetic innervation** to the upper abdominal organs, which can lead to parasympathetic dominance. - This imbalance often results in **increased gastrointestinal motility (diarrhea)** and **vasodilation (hypotension)** as common side effects. *Located retroperitoneally at the level of L3* - The coeliac plexus is typically located **retroperitoneally** at the level of the **T12-L1 vertebrae**, not L3. - Its position is generally superior to the renal arteries, which are closer to L1-L2. *Usually done unilaterally* - A coeliac plexus block is almost always performed **bilaterally** or with a single posterior approach aiming for bilateral spread to effectively block the plexus. - The coeliac plexus is an extensive network, and a unilateral block would likely provide inadequate pain relief. *Useful for painful conditions of the lower abdomen* - The coeliac plexus primarily innervates **upper abdominal organs** (e.g., pancreas, liver, stomach, small intestine, kidneys, adrenal glands). - It is therefore generally **ineffective for lower abdominal pain**, which is innervated by different sympathetic plexuses (e.g., superior and inferior hypogastric plexuses).
Physiology
1 questionsIn bladder injury, pain is referred to which of the following areas?
NEET-PG 2012 - Physiology NEET-PG Practice Questions and MCQs
Question 371: In bladder injury, pain is referred to which of the following areas?
- A. Flank
- B. Upper part of thigh
- C. Lower abdominal wall (Correct Answer)
- D. Penis
Explanation: ***Correct Option: Lower abdominal wall*** - **Referred pain** from the bladder is typically felt in the **suprapubic region** of the lower abdominal wall due to shared visceral and somatic afferent innervation. - The **parietal peritoneum** overlying the bladder is innervated by somatic nerves that also supply the abdominal wall. - This convergence of visceral afferents from the bladder and somatic afferents from the abdominal wall at the spinal cord level (particularly S2-S4) results in referred pain to the suprapubic area. *Incorrect Option: Upper part of thigh* - Pain in the upper thigh is more commonly associated with conditions affecting the **hip joint**, **femoral nerve**, or **inguinal region**. - Bladder innervation does not primarily refer pain to the upper thigh. *Incorrect Option: Flank* - Flank pain is typically associated with conditions of the **kidneys** or **ureters**, such as **nephrolithiasis** or **pyelonephritis**. - The bladder's referred pain pattern does not usually extend to the flank. *Incorrect Option: Penis* - While bladder irritation can sometimes cause sensations in the penis, it is more often associated with conditions like **urethritis**, **cystitis**, or **prostatitis**. - Direct referred pain from bladder injury to the penis is less common than to the lower abdominal wall.