INI-CET 2021 Practice Questions

Q: The marked structure develops from which of the following structures?

Supracardinal vein. ***Supracardinal vein*** - The arrow points to the **azygos vein**, which drains the thoracic wall. - The azygos vein is primarily derived from the right **supracardinal vein**. *Anterior cardinal vein* - The anterior cardinal veins contribute to the formation of the **superior vena cava** and internal jugular veins. - They are located more superiorly and drain the head and upper limbs. *Subcardinal vein* - The subcardinal veins are involved in the formation of the **renal veins**, gonadal veins, and a segment of the inferior vena cava. - These veins are found in the abdominal region, inferolateral to the developing kidneys. *Common cardinal vein* - The common cardinal veins fuse to form the **superior vena cava** and enter the sinus venosus. - They are important in the early embryonic stage for collecting blood from the anterior and posterior cardinal veins.

Q: Inferior thyroid artery supplies which of the following structures? 1. Thyroid 2. Parathyroid 3. Esophagus 4. Thymus

1,2 and 3. ***1,2 and 3*** - The **inferior thyroid artery** is a branch of the **thyrocervical trunk** and supplies the **thyroid gland**, **parathyroid glands**, and the **cervical part of the esophagus** [1]. - It also gives branches to the **trachea** and **larynx** (via the inferior laryngeal artery). - These are the standard, consistently described structures supplied by this artery in anatomical texts. *1 and 2 only* - This option is incomplete as the inferior thyroid artery provides blood supply to more structures than just the thyroid and parathyroid glands. - It also supplies the **cervical portion of the esophagus** through its esophageal branches. *1,2 and 4 only* - This option is incorrect because the inferior thyroid artery does supply the **esophagus** (cervical part), which is missing from this option. - The **thymus** is primarily supplied by branches of the **internal thoracic artery**, not the inferior thyroid artery. *1,2,3 and 4* - This option is incorrect because the **thymus** is NOT a standard structure supplied by the inferior thyroid artery. - The thymus receives its blood supply primarily from the **internal thoracic artery** (anterior mediastinal branches) and sometimes from the **superior thyroid artery**. [1] - The inferior thyroid artery's distribution includes thyroid, parathyroid, esophagus, trachea, and larynx—but not the thymus.

Q: Identify the pelvic diaphragm in the picture given below:

1. ***1*** - Label 1 points to the **levator ani muscle**, which is the primary component of the **pelvic diaphragm**. - The pelvic diaphragm consists of the levator ani and coccygeus muscles, forming the floor of the pelvic cavity. *2* - Label 2 points to the **external anal sphincter**, a voluntary muscle that surrounds the anal canal. - This muscle is superficial to the pelvic diaphragm and is responsible for maintaining fecal continence. *3* - Label 3 points to the **internal anal sphincter**, an involuntary smooth muscle layer intrinsic to the anal canal. - It maintains resting anal tone and is deep to the external anal sphincter. *4* - Label 4 points to the **ischiorectal fossa**, a fat-filled space located on either side of the anal canal. - This space contains vessels and nerves, but it is not part of the muscular pelvic diaphragm.

Q: Third part of vertebral artery is related to which of the following ?

Posterior arch of atlas (C1). ***Posterior arch of atlas (C1)*** - The **third part** of the vertebral artery emerges from the **transverse foramen of C1** and courses laterally and posteriorly around the **posterior arch of the atlas**. - This segment then pierces the **posterior atlanto-occipital membrane** and dura to enter the skull. *Transverse foramina of C2-C6 vertebrae* - This describes the typical course of the **second part** of the vertebral artery, which ascends through the transverse foramina of the cervical vertebrae from **C6 to C2**. - The third part's specific relation is to C1, not the lower cervical vertebrae. *Foramen magnum and intracranial course* - This refers to the **fourth part** of the vertebral artery, which enters the skull through the **foramen magnum** and then runs superiorly to join the other vertebral artery to form the basilar artery. - The third part is extra-cranial, occurring before entry into the skull. *Transverse foramen of C6 vertebra* - The **first part** of the vertebral artery courses superiorly from its origin, typically entering the transverse foramen of the **C6 vertebra**. - The third part is located much higher, at the level of the C1 vertebra.

Q: Identify the type of marked chromosome in the given karyotype.

Acrocentric. ***Acrocentric*** - Acrocentric chromosomes have a **centromere positioned very close to the end**, resulting in one very short arm (p arm) and one long arm (q arm). - Chromosome 13, as indicated by the arrow in the karyotype, clearly exhibits this morphology with a distinctly short p arm. *Metacentric* - **Metacentric chromosomes** have the centromere located approximately in the **middle of the chromosome**, resulting in two arms of roughly equal length. - Examples of metacentric chromosomes in a human karyotype include chromosomes 1, 3, 16, 19, and 20. *Telocentric* - **Telocentric chromosomes** have the **centromere at the very end of the chromosome**, meaning there is essentially only one arm. - This type of chromosome structure is not found in normal human karyotypes. *Submetacentric* - **Submetacentric chromosomes** have the centromere off-center, leading to one arm being **moderately shorter** than the other. - Chromosomes 2, 4-12, 17, 18, and X are generally classified as submetacentric in human karyotypes.

Q: miRNA binds to which part of the mRNA to inhibit translation?

3'UTR. ***3'UTR*** - MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression. - They primarily bind to the **3' untranslated region (3'UTR)** of messenger RNA (mRNA) molecules, leading to translational repression or mRNA degradation. *Gene promoter* - The **gene promoter** is a region of DNA located upstream of a gene, where regulatory proteins bind to initiate transcription. - miRNAs do not directly bind to gene promoters to inhibit translation. *Gene body* - The **gene body** refers to the entire transcribed region of a gene, including exons and introns. - While some regulatory elements can be found within the gene body, the primary binding site for miRNAs to exert translational control is the 3'UTR. *5'UTR* - The **5' untranslated region (5'UTR)** is located at the 5' end of an mRNA molecule, upstream of the start codon. - While the 5'UTR can play a role in regulating translation initiation, it is not the primary target for miRNA binding to inhibit translation.

Q: Which of the following methods cannot be used to precipitate proteins?

Moving pH away from isoelectric pH. ***Moving pH away from isoelectric pH*** - Proteins are **least soluble** at their **isoelectric point (pI)**, where their net charge is zero, causing them to aggregate and precipitate. - Moving the pH **away from the isoelectric point** increases the net charge on the protein, enhancing its solubility and preventing precipitation. *Add alcohol and acetone* - **Organic solvents** like alcohol and acetone reduce the dielectric constant of water, weakening the **hydrophobic interactions** that maintain protein solubility. - This leads to increased protein-protein interactions and **precipitation** as the protein unfolds or aggregates. *Using heavy metal ions* - **Heavy metal ions** (e.g., lead, mercury) are positively charged and bind strongly to the negatively charged groups on proteins, such as **carboxylates** and **sulfhydryl groups**. - This binding can disrupt protein structure, lead to aggregation, and cause **precipitation**. *Adding trichloroacetic acid* - **Trichloroacetic acid (TCA)** is a strong acid that significantly lowers the pH of the solution, causing proteins to become **protonated**. - This change in charge and the disruption of **salt bridges** and hydrogen bonds lead to protein denaturation and **precipitation**.

Q: Which of the following statements are true? 1. Due to increasing mammography there occurs over diagnosis of breast carcinoma 2. Colon cancer screening is done by digital rectal examination 3. Oral cancer screening is done by visual inspection 4. Cervix cancer screening is done by a pap smear

1,3,4. ***Correct: 1,3,4*** - **Statement 1 is TRUE**: Overdiagnosis is a well-documented consequence of increased mammography screening. It detects slow-growing tumors that might never have caused clinical symptoms or harm during a woman's lifetime, leading to unnecessary treatment and associated morbidities. - **Statement 3 is TRUE**: Oral cancer screening primarily involves thorough visual inspection by a healthcare professional to identify suspicious lesions, ulcers, or color changes in the oral cavity. - **Statement 4 is TRUE**: Cervical cancer screening is effectively done by Pap smear, which detects precancerous and cancerous cells. - **Statement 2 is FALSE**: Digital rectal examination is NOT the primary screening method for colon cancer. Standard screening methods include colonoscopy, fecal occult blood testing (FOBT), and fecal immunochemical test (FIT). *Incorrect: 1,2,3,4* - While statements 1, 3, and 4 are true, statement 2 is incorrect. Digital rectal examination is not a primary or definitive screening method for colon cancer—it only examines the rectum and misses most of the colon. *Incorrect: 4 only* - While cervical cancer screening by Pap smear is true, this option is incomplete as it misses other true statements (1 and 3) regarding mammography overdiagnosis and oral cancer screening. *Incorrect: 2,3,4* - This option incorrectly includes statement 2. Colon cancer screening is NOT done by digital rectal examination. Proper screening methods include colonoscopy, FOBT, FIT, and flexible sigmoidoscopy.

Q: A 50 year old male patient came to the outpatient department with complaints of hematuria. A 2 x 2 cm bladder mass is seen which is low grade transitional cell carcinoma. Which among the following is the ideal management?

Transurethral resection of the tumour. ***Transurethral resection of the tumour*** - For a **low-grade transitional cell carcinoma** that is 2x2 cm and thus considered small and localized, **transurethral resection of the tumor (TURBT)** is the initial and often definitive treatment. - This procedure allows for both **diagnosis** by obtaining tissue samples and **complete removal** of the visible tumor. *Resection with ileal conduit* - This option, involving a **radical cystectomy** and urinary diversion, is a more aggressive treatment reserved for **invasive, high-grade, or recurrent bladder cancers** that cannot be managed by less invasive means. - It would be **overtreatment** for a low-grade, relatively small bladder mass. *Partial cystectomy with bladder reconstruction* - **Partial cystectomy** is considered for solitary, muscle-invasive tumors located away from critical areas (like the trigone) when bladder preservation is desirable. - It is generally not the first-line treatment for **non-muscle-invasive, low-grade tumors** due to the potential for recurrence in the remaining bladder and the morbidity of open surgery compared to TURBT. *Neoadjuvant chemotherapy* - **Neoadjuvant chemotherapy** is typically administered before radical cystectomy for **muscle-invasive bladder cancer** to improve oncologic outcomes. - It is not indicated for **low-grade, non-muscle-invasive bladder cancer** which is usually managed surgically first, without systemic chemotherapy.

Question 1

The marked structure develops from which of the following structures?

Accepted Answer

Supracardinal vein

Answer

Anterior cardinal vein

Answer

Subcardinal vein

Answer

Common cardinal vein

Question 2

Inferior thyroid artery supplies which of the following structures?

1. Thyroid
2. Parathyroid
3. Esophagus
4. Thymus

Accepted Answer

1,2 and 3

Answer

1 and 2 only

Answer

1,2 and 4 only

Answer

1,2,3 and 4

Question 3

Identify the pelvic diaphragm in the picture given below:

Accepted Answer

1

Answer

2

Answer

3

Answer

4

Question 4

Third part of vertebral artery is related to which of the following ?

Accepted Answer

Posterior arch of atlas (C1)

Answer

Foramen magnum and intracranial course

Answer

Transverse foramen of C6 vertebra

Answer

Transverse foramina of C2-C6 vertebrae

Question 5

Identify the type of marked chromosome in the given karyotype.

Accepted Answer

Acrocentric

Answer

Metacentric

Answer

Telocentric

Answer

Submetacentric

Question 6

miRNA binds to which part of the mRNA to inhibit translation?

Accepted Answer

3'UTR

Answer

Gene promoter

Answer

Gene body

Answer

5'UTR

Question 7

Which of the following methods cannot be used to precipitate proteins?

Accepted Answer

Moving pH away from isoelectric pH

Answer

Add alcohol and acetone

Answer

Using heavy metal ions

Answer

Adding trichloroacetic acid

Question 8

Which of the following statements are true?

1. Due to increasing mammography there occurs over diagnosis of breast carcinoma
2. Colon cancer screening is done by digital rectal examination
3. Oral cancer screening is done by visual inspection
4. Cervix cancer screening is done by a pap smear

Accepted Answer

1,3,4

Answer

1,2,3,4

Answer

4 only

Answer

2,3,4

Question 9

What would happen to the half-life and plasma concentration of a drug which follows first-order kinetics, if the dose is doubled?

Accepted Answer

Half - life remains the same and plasma concentration doubles

Answer

Half - life and plasma concentration remains the same

Answer

Half - life doubles and plasma concentration remains the same

Answer

Half - life and plasma concentration doubles

Question 10

A 50 year old male patient came to the outpatient department with complaints of hematuria. A 2 x 2 cm bladder mass is seen which is low grade transitional cell carcinoma. Which among the following is the ideal management?

Accepted Answer

Transurethral resection of the tumour

Answer

Resection with ileal conduit

Answer

Partial cystectomy with bladder reconstruction

Answer

Neoadjuvant chemotherapy

INI-CET 2021

Anatomy

Biochemistry

Community Medicine

Pharmacology

Surgery