Which of the following is not a branch of the inferior mesenteric artery?
What is Little's area, also known as Kiesselbach's plexus?
Which of the following is NOT a branch of 1st part of maxillary artery?
Which of the following statements about the Corpus Callosum is correct?
What does Chamberlain's line refer to in anatomical terms?
Development of labia majora is from -
What type of joint is the 1st carpometacarpal joint?
The nutrient artery to the femur is?
The right coronary artery supplies blood to all of the following structures, except?
All of the following arteries are branches of the coeliac trunk, EXCEPT which one?
NEET-PG 2012 - Anatomy NEET-PG Practice Questions and MCQs
Question 41: Which of the following is not a branch of the inferior mesenteric artery?
- A. Left colic
- B. Middle rectal (Correct Answer)
- C. Superior rectal
- D. Sigmoidal artery
Explanation: ***Middle rectal artery*** - The **middle rectal artery** [2] is typically a branch of the **internal iliac artery** [2], supplying the middle part of the rectum. - It is not a direct branch of the inferior mesenteric artery. *Left colic artery* - The left colic artery is a direct branch of the **inferior mesenteric artery** [1], supplying the distal transverse colon and descending colon. - It forms an important anastomosis with the middle colic artery [1]. *Superior rectal artery* - The **superior rectal artery** is the terminal branch of the **inferior mesenteric artery**, supplying the upper rectum. - This artery provides the primary arterial supply to the proximal large intestine structures. *Sigmoidal artery* - The **sigmoidal arteries** are typically 2-4 branches arising from the **inferior mesenteric artery**, supplying the sigmoid colon. - These arteries anastomose with branches of the superior rectal and left colic arteries.
Question 42: What is Little's area, also known as Kiesselbach's plexus?
- A. Anteroinferior lateral wall
- B. Anteroinferior nasal septum (Correct Answer)
- C. Posteroinferior lateral wall
- D. Posteroinferior nasal septum
Explanation: ***Anteroinferior nasal septum*** - **Little's area**, or **Kiesselbach's plexus**, is a well-vascularized region located on the **anteroinferior portion of the nasal septum**. - This area is a common site for **anterior epistaxis** (nosebleeds) due to its superficial position and rich anastomotic blood supply from several arteries. *Anteroinferior lateral wall* - While the lateral nasal wall also contributes to the nasal blood supply, the specific region of **Little's area** is on the **septum**, not the lateral wall. - The **lateral wall** contains structures like the turbinates and their associated vascular networks, which are distinct from Kiesselbach's plexus. *Posteroinferior lateral wall* - The **posterior and inferior aspects** of the nasal cavity are not where Kiesselbach's plexus is predominantly located. - Bleeding from this posterior region often indicates **posterior epistaxis**, which can be more severe and difficult to control. *Posteroinferior nasal septum* - The **posterior nasal septum** is supplied by different arteries, such as branches of the **sphenopalatine artery**. - Bleeding from this part of the septum is also considered **posterior epistaxis** and is not typically associated with Kiesselbach's plexus.
Question 43: Which of the following is NOT a branch of 1st part of maxillary artery?
- A. Accessory meningeal artery
- B. Inferior alveolar artery
- C. Middle meningeal artery
- D. Greater palatine artery (Correct Answer)
Explanation: ***Greater palatine artery*** - This artery is a branch of the **third part** of the maxillary artery, which supplies the palate. - The third part of the maxillary artery (also known as the pterygopalatine part) gives off branches that pass through the pterygopalatine fossa. *Middle meningeal artery* - This is a significant branch of the **first part** of the maxillary artery, entering the cranial cavity via the **foramen spinosum** to supply the dura mater. - It is often injured in head trauma, leading to an **epidural hematoma**. *Accessory meningeal artery* - This artery also arises from the **first part** of the maxillary artery and enters the skull through the **foramen ovale** to supply the dura mater. - It is a smaller branch compared to the middle meningeal artery. *Inferior alveolar artery* - It is a branch of the **first part** of the maxillary artery, descending to enter the mandible via the **mandibular foramen** to supply the teeth and bone of the mandible. - It gives off the **mylohyoid branch** before entering the mandibular foramen.
Question 44: Which of the following statements about the Corpus Callosum is correct?
- A. All of the options
- B. Connects distant areas of the two sides of the brain
- C. Connects the two frontal lobes
- D. Connects the left and right hemispheres (Correct Answer)
Explanation: ***Connects the left and right hemispheres*** - The **corpus callosum** is the largest **commissural white matter tract** in the brain, uniquely designed to facilitate communication between the **corresponding regions** of the left and right cerebral hemispheres [1]. - Its primary function is to integrate **sensory, motor, and cognitive information** processed in each hemisphere, ensuring coordinated brain activity [1]. *Connects distant areas of the two sides of the brain* - While it connects regions on the two sides of the brain, the statement is too broad and does not specify its role in connecting **corresponding** or **homologous** areas across the hemispheres. - Other fiber tracts (e.g., **anterior commissure**) also connect different areas between the two sides, but the corpus callosum is specific to the **cerebral hemispheres**. *Connects the two frontal lobes* - The corpus callosum connects all four lobes (frontal, parietal, temporal, occipital) between the two hemispheres, not exclusively the **frontal lobes**. - While it does contain fibers connecting the frontal lobes, this statement is **incomplete** and does not capture its overall function. *All of the options* - Since the other options are either **incorrect** or **incomplete**, this option cannot be correct. - The most accurate and encompassing description of the corpus callosum's function among the choices is connecting the left and right hemispheres.
Question 45: What does Chamberlain's line refer to in anatomical terms?
- A. Palate to occiput
- B. Palate to temporal
- C. Palate to foramen magnum (Correct Answer)
- D. Palate to parietal
Explanation: ***Palate to foramen magnum*** - **Chamberlain's line** is a measurement used in radiology to assess for **basilar invagination** or impression. - It extends from the **posterior margin of the hard palate** to the **posterior lip of the foramen magnum**. *Palate to occiput* - This description is too general and does not precisely define Chamberlain's line, which specifically uses the **posterior lip of the foramen magnum** as its posterior anchor point. - While the foramen magnum is within the occipital bone, "occiput" can refer to a broader area. *Palate to temporal* - The **temporal bone** is not part of the anatomical landmarks used for Chamberlain's line. - This line is focused on structures in the midline skull base. *Palate to parietal* - The **parietal bone** is located superiorly and laterally to the structures involved in Chamberlain's line. - It is not used as a landmark for this specific measurement.
Question 46: Development of labia majora is from -
- A. Urogenital sinus
- B. Mullerian duct
- C. Genital ridge
- D. Genital swelling (Correct Answer)
Explanation: ***Genital swelling*** - The **labia majora** develop from the **genital (labioscrotal) swellings** in females, which are homologous to the scrotum in males [3]. - These swellings enlarge and fuse anteriorly to form the mons pubis and posteriorly to form the posterior commissures of the labia majora. *Urogenital sinus* - The **urogenital sinus** gives rise to structures like the **bladder**, **urethra**, and parts of the **vagina** in females [2]. - It does not contribute to the formation of the external labial structures. *Mullerian duct* - The **Mullerian (paramesonephric) ducts** develop into the **fallopian tubes**, **uterus**, and the **upper third of the vagina** [1], [2]. - These structures are internal reproductive organs and do not form external genitalia like the labia majora. *Genital ridge* - The **genital ridge** is the embryonic precursor to the **gonads** (ovaries or testes). - It differentiates into either ovaries or testes and does not directly form external genital structures.
Question 47: What type of joint is the 1st carpometacarpal joint?
- A. Pivot
- B. Hinge
- C. Ball and Socket
- D. Saddle (Correct Answer)
Explanation: ***Saddle*** - The **1st carpometacarpal joint** (thumb CMC joint) is a classic example of a **saddle joint** due to the reciprocal concave-convex opposing surfaces of the trapezium and the first metacarpal [1]. - This unique shape allows for a wide range of motion, including **flexion/extension**, **abduction/adduction**, and **opposition**, which is crucial for thumb function. *Pivot* - A **pivot joint** allows for rotational movement around a single axis, like the **atlantoaxial joint** (C1-C2) or the **proximal radioulnar joint**. - This type of motion is not characteristic of the 1st carpometacarpal joint. *Hinge* - A **hinge joint** permits movement in only one plane, like the **elbow** or **interphalangeal joints**, allowing for **flexion and extension**. - The 1st carpometacarpal joint has a greater degree of freedom than a hinge joint. *Ball and Socket* - A **ball and socket joint** offers the greatest range of motion, allowing for movement in all planes, including **circumduction and rotation**, such as the **shoulder** and **hip joints**. - While the 1st carpometacarpal joint is highly mobile, it does not achieve the full range of motion of a ball and socket joint.
Question 48: The nutrient artery to the femur is?
- A. Profunda femoris artery (Correct Answer)
- B. Femoral artery
- C. Popliteal artery
- D. Medial circumflex femoral artery
Explanation: ***Profunda femoris artery*** - The **profunda femoris artery** (deep femoral artery) is the main blood supply to the **femur's diaphysis** via its perforating branches. - Typically, the **second perforating branch** gives rise to the nutrient artery, which enters the bone through the **nutrient foramen** in the middle third of the femoral shaft. *Femoral artery* - The **femoral artery** is the main artery of the thigh and gives off several branches, including the profunda femoris artery. - While it is the source of blood for the entire lower limb, it does not directly give rise to the main **nutrient artery of the femur**. *Popliteal artery* - The **popliteal artery** is a continuation of the femoral artery in the popliteal fossa behind the knee. - It primarily supplies structures around the knee joint and the lower leg, not the direct **diaphyseal nutrient supply** to the femur. *Medial circumflex femoral artery* - The **medial circumflex femoral artery** primarily supplies the head and neck of the femur, crucial for its vascularity, especially in children. - It does not serve as the **main nutrient artery** for the femoral shaft (diaphysis).
Question 49: The right coronary artery supplies blood to all of the following structures, except?
- A. Posterior wall of left ventricle
- B. SA node
- C. Anterior 2/3 of ventricular septum (Correct Answer)
- D. AV node
Explanation: ***Anterior 2/3 of ventricular septum*** - The **anterior two-thirds of the interventricular septum** is primarily supplied by the **septal branches of the left anterior descending artery** (LAD) [1], a branch of the left coronary artery. - Therefore, the right coronary artery does not typically supply this region. *SA node* - The **SA node** (sinoatrial node) is the heart's natural pacemaker and receives its blood supply from the **right coronary artery** in about 60% of individuals. - Occlusion of the RCA can lead to symptomatic **bradycardia** or **SA node dysfunction**. *AV node* - The **AV node** (atrioventricular node), crucial for coordinating ventricular contraction, is supplied by the **right coronary artery** in approximately 90% of individuals [1]. - Infarcts in the RCA territory can manifest as various degrees of **heart block**. *Posterior wall of left ventricle* - The **posterior wall of the left ventricle** is predominantly supplied by the **posterior descending artery (PDA)**, which in about 80% of people, is a terminal branch of the **right coronary artery** [1]. - This supply is vital for the contractile function of the left ventricle's posterior aspect.
Question 50: All of the following arteries are branches of the coeliac trunk, EXCEPT which one?
- A. Splenic artery
- B. Left gastric artery
- C. Common hepatic artery
- D. Right gastric artery (Correct Answer)
Explanation: ***Right gastric artery*** - The **right gastric artery** typically originates from the **proper hepatic artery**, which is a branch of the common hepatic artery. - Therefore, it is not a direct branch of the coeliac trunk itself. *Left gastric artery* - The **left gastric artery** is one of the three main direct branches of the **coeliac trunk**. - It supplies the lesser curvature of the stomach and the abdominal esophagus. *Splenic artery* - The **splenic artery** is another major direct branch of the **coeliac trunk**. - It supplies the spleen, pancreas, and parts of the stomach via various branches. *Common hepatic artery* - The **common hepatic artery** is the third main direct branch of the **coeliac trunk**. - It gives rise to the proper hepatic artery and the gastroduodenal artery, supplying the liver, gallbladder, pylorus, and duodenum.