Anatomy
10 questionsRight border of heart is formed by?
Which of the following statements about the anatomy of the right ventricle is correct?
Which of the following does not directly drain into right atrium?
What is the average number of lobes in a human breast?
Which artery supplies the anterior part of the interventricular septum?
Which of the following statements about the atrioventricular groove is true?
Insertion of levator scapulae is?
Which of the following vessels runs through the transverse mesocolon?
All veins open in sinus venarum except -
Distance of cricopharynx from incisor teeth
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 61: Right border of heart is formed by?
- A. Right ventricle
- B. Right atrium (Correct Answer)
- C. SVC
- D. IVC
Explanation: ***Right atrium*** - The **right atrium** forms the major part of the **right border of the heart** as viewed in a posteroanterior (PA) chest X-ray. - Its position is along the right sternal margin, extending from the level of the third costal cartilage superiorly to the sixth costal cartilage inferiorly. *Right ventricle* - The **right ventricle** primarily forms the **anterior surface** and part of the inferior border of the heart. - It contributes minimally, if at all, to the visible right border in a standard PA view. *SVC* - The **superior vena cava (SVC)** drains into the right atrium and is located superior to it. - While it's adjacent to the right border, it does **not form the actual right border of the heart itself**. *IVC* - The **inferior vena cava (IVC)** drains into the right atrium from below. - It is positioned inferiorly and posteriorly, and therefore **does not form the right border** of the heart in a PA view.
Question 62: Which of the following statements about the anatomy of the right ventricle is correct?
- A. TV & PV Share fibrous continuity
- B. More prominent trabeculation
- C. The crista supraventricularis separates the tricuspid and pulmonary valves, and the apex is trabeculated (Correct Answer)
- D. All of the options
Explanation: The crista supraventricularis separates the tricuspid and pulmonary valves, and the apex is trabeculated - The **crista supraventricularis** (also known as the supraventricular crest) is a prominent muscular ridge that separates the **inflow tract** (tricuspid valve region) from the **outflow tract** (pulmonary valve region) in the right ventricle. - The **apex and trabecular portion** of the right ventricle contains prominent **trabeculae carneae**, which are irregular muscular ridges and columns. - This option is correct as it describes two key anatomical features: the structural separator between valves and the trabeculated apex. *TV & PV Share fibrous continuity* - This statement is **anatomically incorrect** for the right ventricle. - The **tricuspid valve** and **pulmonary valve** do NOT share fibrous continuity; they are separated by the **crista supraventricularis** (muscular ridge). - **Fibrous continuity** (mitral-aortic continuity) is a characteristic feature of the **left heart**, where the anterior mitral leaflet is continuous with the aortic valve, but this does NOT occur in the right ventricle. *More prominent trabeculation* - While this statement is **anatomically true** (the right ventricle has more prominent trabeculation than the left ventricle, which has a smoother wall), this option is **incomplete** when compared to the correct answer. - The question asks for the correct statement about right ventricle anatomy, and option 3 provides a **more comprehensive description** that includes both a unique structural landmark (crista supraventricularis) and the trabeculation feature. - In single-best-answer format, the most complete and specific option is preferred. *All of the options* - This option is incorrect because the statement "TV & PV Share fibrous continuity" is anatomically false. - Since not all options are correct, this cannot be the answer.
Question 63: Which of the following does not directly drain into right atrium?
- A. Inferior vena cava
- B. Great cardiac vein (Correct Answer)
- C. Anterior cardiac vein
- D. Venae cordis minimi
Explanation: ***Great cardiac vein*** - The **great cardiac vein** drains into the **coronary sinus**, which then empties into the right atrium [1]. - It does not drain directly into the right atrium, distinguishing it from the other options. *Inferior vena cava* - The **inferior vena cava** is one of the major vessels that drains directly into the **right atrium**. - It carries deoxygenated blood from the lower body to the right atrium. *Anterior cardiac vein* - The **anterior cardiac veins** drain directly into the **right atrium**. - They tend to drain the anterior surface of the right ventricle. *Venae cordis minimi* - Also known as **Thebesian veins**, these are small veins that drain directly into the cardiac chambers, including the **right atrium**. - They represent a direct communication between the myocardial capillaries and the cardiac chambers.
Question 64: What is the average number of lobes in a human breast?
- A. 5
- B. 10
- C. 15 (Correct Answer)
- D. 20
Explanation: ***15*** - Historically, the human breast was described as containing **15 to 20 lobes**, each being a functionally distinct unit for milk production arranged radially around the nipple [1]. - This was the accepted anatomical teaching at the time of this examination. - **Note:** Modern imaging studies (MRI, ultrasound) have since shown that breasts typically contain **7-10 ductal systems/lobes** rather than 15-20, representing an important update to classical anatomy teaching. *5* - This number is too low and does not represent either the classical (15-20) or modern (7-10) understanding of breast lobe anatomy. - Insufficient to account for the complexity of the mammary ductal system. *10* - This represents the **upper range of modern anatomical understanding** (7-10 lobes based on current imaging studies). - While anatomically accurate by today's standards, the classical teaching referenced in this examination specified 15-20 lobes as average. *20* - Represents the **upper limit** of the classical range (15-20 lobes) [1]. - While within the historical normal range, **15 is considered the more typical average** in classical anatomy texts. - Modern research indicates this number significantly overestimates the actual lobe count.
Question 65: Which artery supplies the anterior part of the interventricular septum?
- A. Right coronary artery
- B. Posterior descending coronary artery
- C. Left anterior descending artery (LAD) (Correct Answer)
- D. None of the options
Explanation: ***Left anterior descending artery (LAD)*** - The **LAD** is a branch of the **left main coronary artery** and is also known as the "widowmaker" due to its critical supply to a large portion of the left ventricle and the interventricular septum [1]. - It gives rise to **septal branches** that typically supply the anterior two-thirds of the interventricular septum [1]. *Right coronary artery* - The **right coronary artery (RCA)** primarily supplies the **right ventricle**, the right atrium, the SA node (in 60% of people), and the AV node (in 90% of people). - It typically supplies the **inferior wall** of the left ventricle and the posterior one-third of the interventricular septum [1]. *Posterior descending coronary artery* - The **posterior descending artery (PDA)** arises from the **RCA** (in approximately 85% of individuals, known as right dominance) or less commonly from the circumflex artery (in left dominance) [1]. - It supplies the **posterior one-third** of the interventricular septum and typically the inferior wall of the left ventricle [1]. *None of the options* - This option is incorrect because the **LAD** clearly and predominantly supplies the anterior part of the interventricular septum.
Question 66: Which of the following statements about the atrioventricular groove is true?
- A. Contains left anterior descending coronary artery
- B. Also called coronary sulcus (Correct Answer)
- C. Contains posterior descending artery
- D. Contains left coronary artery
Explanation: ***Also called coronary sulcus*** - The **atrioventricular groove** is a critical anatomical landmark that separates the atria from the ventricles on the external surface of the heart. - This anatomical division is consistently referred to as the **coronary sulcus**, which encircles the entire heart. *Contains left anterior descending coronary artery* - The **left anterior descending (LAD) coronary artery**, also known as the anterior interventricular artery, lies within the **interventricular groove** (or sulcus), not the atrioventricular groove. - The interventricular groove separates the left and right ventricles, distinct from the atrioventricular separation. *Contains left coronary artery* - The **left coronary artery (LCA)** is a short main trunk that almost immediately divides into the **left anterior descending** (LAD) and **circumflex arteries** [1]. - While the **circumflex artery** (a branch of the LCA) runs in the left part of the atrioventricular groove, the main left coronary artery itself is too short to be considered within the groove [1]. *Contains posterior descending artery* - The **posterior descending artery (PDA)**, also known as the posterior interventricular artery, lies within the **posterior interventricular groove**, separating the ventricles posteriorly. - The PDA is a branch of either the right coronary artery (in most people) or the circumflex artery, but it follows the interventricular septum, not the atrioventricular border.
Question 67: Insertion of levator scapulae is?
- A. Lateral border of scapula
- B. Suprolateral part of scapula
- C. Superior part of medial scapula border (Correct Answer)
- D. Inferior angle of scapula
Explanation: ***Superior part of medial scapula border*** - The **levator scapulae muscle** originates from the **transverse processes of C1-C4 vertebrae** and **inserts** onto the superior part of the medial border of the scapula, between the **superior angle and the spine of the scapula**. - Its main actions are to **elevate** and **rotate** the scapula downward. *Lateral border of scapula* - The **lateral border of the scapula** primarily serves as the attachment site for muscles that move the **humerus**, such as the **teres major** and **teres minor**. - The levator scapulae has no direct insertion on the lateral border. *Suprolateral part of scapula* - This general description is vague and does not precisely identify the insertion point of the levator scapulae. - While it's located superiorly, the specific insertion is on the **medial border**, not broadly "suprolateral." *Inferior angle of scapula* - The **inferior angle of the scapula** is the insertion point for muscles like the **latissimus dorsi** (occasionally) and a key landmark for muscles involved in **scapular rotation**, such as the **serratus anterior**. - The levator scapulae is located much more superiorly and inserts onto the medial border at a higher level than the inferior angle.
Question 68: Which of the following vessels runs through the transverse mesocolon?
- A. Right colic artery
- B. Left colic artery
- C. Middle colic artery (Correct Answer)
- D. Iliocolic artery
Explanation: * **Middle colic artery** - The **middle colic artery** arises from the superior mesenteric artery and supplies the **transverse colon**, traversing between the two layers of the **transverse mesocolon** [1]. - Its location within the mesocolon makes it susceptible to injury during surgical procedures involving the transverse colon [2]. * *Right colic artery* - The **right colic artery** supplies the **ascending colon** and the right colic flexure, typically lying within retroperitoneal tissue and not the transverse mesocolon itself [2]. - It arises from the superior mesenteric artery but branches to supply structures primarily to the right side of the abdominal cavity. * *Left colic artery* - The **left colic artery** arises from the **inferior mesenteric artery** and supplies the descending colon and the left colic flexure [1]. - This vessel is located within the retroperitoneum and is not associated with the transverse mesocolon. * *Iliocolic artery* - The **iliocolic artery** is a terminal branch of the superior mesenteric artery, supplying the **ileum, cecum, appendix**, and beginning of the ascending colon. - It descends retroperitoneally to reach these structures and does not traverse the transverse mesocolon.
Question 69: All veins open in sinus venarum except -
- A. SVC
- B. Coronary sinus
- C. Anterior cardiac vein (Correct Answer)
- D. Small cardiac vein
Explanation: ***Anterior cardiac vein*** - The **anterior cardiac veins** are unique in that they drain **directly into the right atrium** through small openings (foramina) in the anterior atrial wall, **bypassing the sinus venarum entirely**. - Unlike other cardiac veins, they do **not** drain into the **coronary sinus** or the **sinus venarum**. - They typically number 2-3 veins and drain the anterior surface of the right ventricle. *SVC* - The **superior vena cava (SVC)** opens directly into the **superior part of the sinus venarum** of the right atrium. - It carries deoxygenated blood from the upper body, head, neck, and upper limbs to the heart. *Coronary sinus* - The **coronary sinus** is the largest venous drainage channel of the heart and opens into the **posteromedial part of the sinus venarum**. - It collects blood from most cardiac veins, including the great cardiac vein, middle cardiac vein, and small cardiac vein. *Small cardiac vein* - The **small cardiac vein** drains into the **coronary sinus**, which then opens into the **sinus venarum**. - It runs along the right atrioventricular (coronary) groove and drains the right atrium and right ventricle.
Question 70: Distance of cricopharynx from incisor teeth
- A. 22 cm
- B. 27 cm
- C. 40 cm
- D. Approximately 15 cm (Correct Answer)
Explanation: ***Approximately 15 cm*** - The **cricopharynx** (upper esophageal sphincter at C6 level), which is the narrowest part of the pharynx, is typically located about **15 cm** from the incisor teeth in adults. - This anatomical landmark is crucial in procedures such as **endoscopy**, **intubation**, and **nasogastric tube insertion** to avoid injury. *22 cm* - This distance corresponds to the level of the **aortic arch** (second physiological narrowing of the esophagus). - This is where the aorta crosses anterior to the esophagus, creating the broncho-aortic constriction. *27 cm* - A distance of 27 cm from the incisor teeth corresponds to the level where the **left main bronchus** crosses the esophagus (third physiological narrowing). - This is well beyond the location of the **cricopharynx** and represents the mid-esophageal region. *40 cm* - This measurement represents the approximate total length of the **esophagus**, reaching the **gastroesophageal junction** at the level of the **diaphragmatic hiatus** (cardia of the stomach). - The **cricopharynx** is at the very beginning of this path, much closer to the incisors.