INI-CET 2017 - Anatomy PYQs Practice Questions

Q: Which of the following area is marked in the histology of lymph node? (AIIMS May 2017)

Germinal center. ***Germinal center*** - The image illustrates a **germinal center**, characterized by its **lighter staining** and a distinct network of cells (likely follicular dendritic cells) which are responsible for B-cell proliferation and differentiation. - The pointer indicates the surrounding, more basophilic lymphocytes, often seen adjacent to the paler germinal center. *Mantle zone* - The mantle zone surrounds the germinal center and consists of **small, inactive B-lymphocytes** that stain more densely (darker) than the cells within the germinal center. - It would be seen as a darker ring immediately outside the lighter germinal center. *Marginal zone* - The marginal zone is typically found in the **spleen** and is a region of B cells that surrounds the white pulp. - It is not a primary structural component identified within the follicular architecture of a lymph node in the manner depicted. *Paracortical area* - The paracortex is primarily a **T-cell zone**, located between the follicles and the medulla within the lymph node. - It would not exhibit the distinct follicular structure with a light center and surrounding darker cells as shown. [Practice more Anatomy PYQs on OnCourse]

Q: Which of the following layers has abundance of desmosomes? (AIIMS Nov 2017)

C. ***C*** - Layer C represents the **stratum spinosum** (prickle cell layer) of the epidermis, which is characterized by abundant **desmosomes**. - These desmosomes give the cells a **prickly appearance** when stained, as the cells shrink but the desmosomal attachments remain, pulling on the cell membranes. *A* - Layer A represents the **stratum corneum**, which is the outermost layer consisting of flattened, anucleated cells filled with **keratin**. - While desmosomes are present deeper in the epidermis, this layer is primarily involved in **protection** and shedding of dead cells. *B* - Layer B represents the **stratum granulosum**, characterized by cells containing **keratohyalin granules**. - These granules are precursors to keratin, and while desmosomes connect cells here, they are less prominent than in the stratum spinosum. *D* - Layer D represents the **stratum basale** (basal layer), which is the deepest epidermal layer of cuboidal or columnar cells. - These cells are responsible for **cell proliferation** and connect to the basement membrane via **hemidesmosomes**, and to each other via desmosomes, but not as abundantly as in the stratum spinosum. [Practice more Anatomy PYQs on OnCourse]

Q: An intra-operative photograph of cortical mastoidectomy is shown. Identify the lateral semi-circular canal. (AIIMS Nov 2017)

D. ***Correct Option D*** - The diagram shows a simplified view of the temporal bone anatomy post-mastoidectomy, and 'D' clearly points to the position of the **lateral semicircular canal**. - During cortical mastoidectomy, the **lateral semicircular canal** is typically identified in the superior and posterior wall of the mastoid cavity, just above the aditus and facial nerve. - This is a critical landmark during mastoid surgery as injury to it can cause vertigo and hearing loss. *Incorrect Options A, B, and C* - These labels point to other anatomical structures visible in the mastoid cavity during cortical mastoidectomy, such as the tegmen tympani, facial nerve, sigmoid sinus, or other osseous landmarks. - Proper identification of the lateral semicircular canal is essential to avoid iatrogenic injury during surgery. [Practice more Anatomy PYQs on OnCourse]

Q: Which of the following bones is the first one to ossify?

C. ***C*** - The **capitate bone** is the first carpal bone to ossify, typically appearing around **1-3 months** of postnatal life. - As the largest carpal bone, its early ossification serves as an important radiological marker for assessing **skeletal maturity** in pediatric patients. *A* - The **scaphoid bone** ossifies much later, around **5-6 years** of age, making it one of the last carpal bones to develop. - Due to its **retrograde blood supply**, the scaphoid is particularly susceptible to **avascular necrosis** following fractures. *B* - The **trapezoid bone** typically begins ossification between **4-6 years** of age, significantly later than the capitate. - Located between the **trapezium and capitate**, it forms part of the distal carpal row and contributes to **index finger stability**. *D* - The **lunate bone** usually starts ossifying around **2-4 years** of age, making it the second carpal bone to ossify after the capitate. - The lunate is clinically significant as it's commonly affected by **Kienböck's disease** (avascular necrosis) and **perilunate dislocations**. [Practice more Anatomy PYQs on OnCourse]

Q: Which of the following structures will help in opening of jaw?

C. ***C*** - Structure C represents the **lateral pterygoid muscle**, which is the primary muscle responsible for **opening the jaw (depression of the mandible)**, as well as protrusion and contralateral excursion. - It is the only muscle of mastication that actively participates in jaw opening. *A* - Structure A appears to be the **medial pterygoid muscle**, which is primarily involved in **elevation of the mandible** (jaw closing) and side-to-side movements. - Its action is antagonistic to jaw opening. *B* - Structure B likely represents the **masseter muscle**, a powerful muscle of mastication that primarily functions to **elevate the mandible** and close the jaw. - It is a strong jaw closer, not an opener. *D* - Structure D points to the **temporalis muscle**, another major muscle of mastication that is responsible for **elevating and retracting the mandible** (closing the jaw). - Its primary actions are in jaw closing, not opening. [Practice more Anatomy PYQs on OnCourse]

Question 1

Which of the following area is marked in the histology of lymph node? (AIIMS May 2017)

Accepted Answer

Germinal center

Answer

Mantle zone

Answer

Marginal zone

Answer

Paracortical area

Question 2

Which of the following layers has abundance of desmosomes? (AIIMS Nov 2017)

Accepted Answer

C

Answer

A

Answer

B

Answer

D

Question 3

An intra-operative photograph of cortical mastoidectomy is shown. Identify the lateral semi-circular canal. (AIIMS Nov 2017)

Accepted Answer

D

Answer

A

Answer

B

Answer

C

Question 4

Which of the following bones is the first one to ossify?

Accepted Answer

C

Answer

A

Answer

B

Answer

D

Question 5

Which of the following structures will help in opening of jaw?

Accepted Answer

C

Answer

A

Answer

B

Answer

D

Question 6

Identify the structure marked by the arrow in this skull base image:

Accepted Answer

Vertebral artery

Answer

Spinal accessory nerve

Answer

Labyrinthine artery

Answer

Abducens nerve

Question 7

Which of the following has holocrine secretion?

Accepted Answer

Sebaceous gland

Answer

Salivary gland

Answer

Mammary gland

Answer

Sweat gland

Question 8

Which of the following proteins are not seen in the region marked in the image?

Accepted Answer

Zona occludens

Answer

Macula adherens

Answer

Fascia adherens

Answer

Connexons

Question 9

Which of the following is the constituent of the marked area in the given electron microscope picture of the muscle?

Accepted Answer

$\alpha$-actinin

Answer

Nebulin

Answer

Titin

Answer

Tropomodulin

INI-CET 2017 — Anatomy