Biochemistry
1 questionsWhich of these is not a part of extracellular matrix:
NEET-PG 2015 - Biochemistry NEET-PG Practice Questions and MCQs
Question 1001: Which of these is not a part of extracellular matrix:
- A. Collagen
- B. Laminin
- C. Fibronectin
- D. Integrins (Correct Answer)
Explanation: ***Integrins*** - Integrins are **transmembrane receptors** on the cell surface that facilitate cell-extracellular matrix (ECM) adhesion and cell-cell adhesion. - They are part of the cell membrane, **not** an extracellular component. *Laminin* - **Laminin** is a major protein component of the **basal lamina**, a specialized extracellular matrix that underlies epithelial cells. - It plays a crucial role in cell adhesion, differentiation, and migration within the ECM. *Fibronectin* - **Fibronectin** is a large glycoprotein present in the **extracellular matrix** and in soluble form in blood plasma. - It mediates cell adhesion to the ECM by binding to integrins and various ECM components like collagen and proteoglycans. *Collagen* - **Collagen** is the most abundant protein in the human body and a primary structural component of the **extracellular matrix**. - It provides tensile strength and structural integrity to tissues like skin, bone, tendons, and cartilage.
Obstetrics and Gynecology
9 questionsWhich of the following is the PRIMARY risk factor for cervical carcinoma?
What is the most common cause of death in cervical cancer?
Which of the following is not a standard treatment option for CIN III?
What size of Hegar's dilator, when passed through the internal os, indicates cervical incompetence?
Funneling in cervicogram is seen in -
Contracted pelvis is defined as a condition where the dimensions of the pelvis are reduced, making childbirth difficult. What is the minimum shortening of one or more planes that is considered significant?
What is the most common type of conjoint twin?
Uterine height is greater than gestational age of the patient in a case of all except -
Following delivery, a tear involving the perineum and external anal sphincter with intact mucosa is classified as which grade?
NEET-PG 2015 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 1001: Which of the following is the PRIMARY risk factor for cervical carcinoma?
- A. Human papilloma virus (Correct Answer)
- B. Smoking
- C. Low socioeconomic status
- D. All of the options
Explanation: ***Human papilloma virus*** - **High-risk HPV types**, particularly **HPV 16 and 18**, are the primary causative agent of cervical carcinoma, responsible for over 90% of cases. - HPV infection is the **most significant and essential risk factor**, leading to persistent changes in cervical cells that can progress to **dysplasia** and eventually **invasive cancer**. - Cervical cancer is considered an **HPV-associated malignancy**, making HPV the central etiological factor. *Smoking* - **Smoking** is an important cofactor that increases the risk of cervical carcinoma in women with HPV infection, but it is not the primary cause. - Smoking impairs the immune system's ability to clear HPV infections and promotes progression of HPV-induced lesions. - Without HPV infection, smoking alone does not cause cervical cancer. *Low socioeconomic status* - **Low socioeconomic status** is an indirect risk factor associated with reduced access to healthcare and **cervical cancer screening** (Pap smears). - It does not directly cause cervical cancer but leads to delayed diagnosis and treatment, resulting in poorer outcomes. *All of the options* - While all listed factors influence cervical carcinoma risk, **Human papillomavirus (HPV)** is the primary and essential causative agent. - The other factors are cofactors or indirect associations, not primary causes.
Question 1002: What is the most common cause of death in cervical cancer?
- A. Infection
- B. Haemorrhage
- C. Metastasis to vital organs
- D. Renal failure (Correct Answer)
Explanation: ***Renal failure*** - As cervical cancer progresses, it can invade surrounding structures, including the **ureters**. - **Ureteral obstruction** leads to **hydronephrosis** and ultimately **renal failure**, which is a common cause of death. *Infection* - While infections can occur due to immunosuppression or compromised tissue integrity in advanced cancer, they are generally **not the most common direct cause of death**. - Infections are often secondary complications rather than the primary mode of mortality. *Haemorrhage* - Local invasion of blood vessels by advanced cervical cancer can cause **significant bleeding** (haemorrhage). - While potentially life-threatening, it is **less frequent** as a direct cause of death compared to renal failure. *Metastasis to vital organs* - Cervical cancer can metastasize to distant organs like the lungs, liver, or bone; however, direct organ failure solely due to metastases is **less common than renal complications** from local tumor spread. - The impact of metastases often contributes to overall decline but is not the most frequent immediate cause of death.
Question 1003: Which of the following is not a standard treatment option for CIN III?
- A. LLETZ
- B. Conization
- C. Hysterectomy
- D. Wertheim's hysterectomy (Correct Answer)
Explanation: ***Wertheim's hysterectomy*** - A **Wertheim's hysterectomy**, also known as a **radical hysterectomy**, involves removal of the uterus, cervix, parametrium, and upper vagina, along with pelvic lymph node dissection. This is typically reserved for **invasive cervical cancer**, not CIN III. - While hysterectomy can be a treatment option for CIN III in specific circumstances (e.g., patient preference, coexisting uterine pathology), a Wertheim's hysterectomy is an **overly aggressive procedure** for precancerous lesions due to its significant morbidity. *LLETZ* - **Large Loop Excision of the Transformation Zone (LLETZ)**, also known as LEEP (Loop Electrosurgical Excision Procedure), is a common and effective outpatient treatment for CIN III. - It involves using a heated wire loop to **excise the abnormal tissue** from the cervix, allowing for histological examination. *Conization* - **Cold knife conization** involves excising a cone-shaped piece of tissue from the cervix using a scalpel. This method is highly effective for CIN III. - It provides **excellent pathological specimens** for evaluation of margins, which is crucial for confirming complete removal of the lesion. *Hysterectomy* - **Hysterectomy** (removal of the uterus, usually simple hysterectomy) can be considered a treatment option for CIN III, particularly in women who have completed childbearing and have other indications for hysterectomy, or when repeated excisional procedures have failed. - While effective, it is a more **invasive procedure** than LLETZ or conization and generally reserved for specific cases where conservative management is not suitable or desired.
Question 1004: What size of Hegar's dilator, when passed through the internal os, indicates cervical incompetence?
- A. 4
- B. 6
- C. 10
- D. 8 or more (Correct Answer)
Explanation: ***8 or more*** - The passage of a **Hegar's dilator of size 8 mm or larger** through the internal os without resistance is a classic diagnostic criterion for **cervical incompetence** or insufficiency. - This finding suggests a **weakened cervix** that is unable to withstand the pressure of a growing pregnancy, leading to recurrent mid-trimester pregnancy losses or preterm births. *4* - A Hegar's dilator of size 4 mm is relatively small and can often pass through a normal, non-pregnant **cervical os** without indicating pathology. - This size would not be considered abnormal and does not signify **cervical incompetence**. *6* - While a Hegar's dilator of 6 mm is larger than 4 mm, it is still generally within the range that might pass through a normal cervix, especially in **multiparous women**, without definitively diagnosing incompetence. - The threshold for diagnosing **cervical incompetence** is typically set higher, at 8 mm or more. *10* - While the passage of a 10 mm Hegar's dilator would certainly indicate **cervical incompetence**, the diagnostic cutoff is typically considered to be **8 mm or more**. - Any dilator **equal to or greater than 8 mm** confirms the diagnosis, so 10 mm is not the *only* size indicating incompetence.
Question 1005: Funneling in cervicogram is seen in -
- A. Cervical ectopic
- B. During TVS
- C. During labor
- D. Weak cervical tissue leading to pregnancy complications (Correct Answer)
Explanation: ***Weak cervical tissue leading to pregnancy complications*** - **Funneling** in a cervicogram (or during transvaginal ultrasound) indicates the shortening and dilation of the internal cervical os, forming a funnel shape. - This finding is a key indicator of **cervical insufficiency** or **weak cervical tissue**, which significantly increases the risk of preterm birth and other pregnancy complications due to the inability of the cervix to retain the pregnancy. *During labor* - While the cervix dilates and effaces during labor, the term "funneling" specifically refers to the premature opening of the internal os seen *before* active labor, often indicative of **cervical insufficiency**. - During active labor, the entire cervix generally dilates progressively, rather than forming a distinct funnel shape. *Cervical ectopic* - A **cervical ectopic pregnancy** involves the implantation of a fertilized egg within the cervical canal. - While it affects the cervix, the defining characteristic is the presence of an implanted gestational sac, not specifically cervical funneling. *During TVS* - **Transvaginal ultrasound (TVS)** is the primary method used to assess cervical length and detect funneling. - Funneling itself is a sign of cervical changes, observed *via* TVS, rather than TVS *causing* or *being* the funneling.
Question 1006: Contracted pelvis is defined as a condition where the dimensions of the pelvis are reduced, making childbirth difficult. What is the minimum shortening of one or more planes that is considered significant?
- A. 1.5 cm (Correct Answer)
- B. 0.5 cm
- C. 1.25 cm
- D. 1 cm
Explanation: ***1.5 cm*** - A reduction of **1.5 cm or more** in any of the pelvic planes is widely accepted as **clinically significant** to define a contracted pelvis. - Most standard obstetric textbooks (including Williams Obstetrics and DC Dutta) cite **1.5-2 cm** as the threshold for clinically significant pelvic contraction. - This degree of shortening can impede the normal mechanism of labor and increase the risk of **cephalopelvic disproportion**. *1 cm* - While some older references mention 1 cm, the **generally accepted minimum threshold** in modern obstetric practice is **1.5-2 cm**. - A reduction of only 1 cm may not consistently cause significant obstetric complications and falls within the range of normal variation in many cases. *1.25 cm* - This value is **below the standard threshold** of 1.5-2 cm used to define a contracted pelvis in most authoritative obstetric texts. - While it represents some reduction, it does not meet the minimum accepted criterion for clinical significance. *0.5 cm* - A shortening of **0.5 cm** is **insufficient** to classify a pelvis as contracted. - Minor variations within this range fall within the **normal spectrum** and do not typically cause labor complications.
Question 1007: What is the most common type of conjoint twin?
- A. Thoracopagus (Correct Answer)
- B. Omphalopagus
- C. Craniopagus
- D. Rachipagus
Explanation: ***Thoracopagus*** - This type of conjoint twin, fused at the **thorax** and often sharing a heart and liver, is the **most common** variety, accounting for approximately **40%** of all cases. - The shared organs and complex anatomy often pose significant challenges for separation and survival. *Omphalopagus* - These twins are joined at the **abdomen** and typically share a liver, gastrointestinal tract, or other abdominal organs. - This is the second most common type, representing approximately **30-35%** of conjoint twins. *Craniopagus* - This rare form involves fusion at the **head**, often sharing parts of the skull, dura mater, or even brain tissue. - Due to the intricate neurological connections, craniopagus twins present exceptionally complex medical and ethical challenges, accounting for only **2-6%** of cases. *Rachipagus* - These twins are fused dorsally along the **spine** and typically share portions of the vertebral column and spinal cord. - This is an extremely rare type of conjoint twinning, representing less than **2%** of cases.
Question 1008: Uterine height is greater than gestational age of the patient in a case of all except -
- A. Fibroid uterus
- B. Wrong dates
- C. Polyhydramnios
- D. IUGR (Correct Answer)
Explanation: ***IUGR*** - In **Intrauterine Growth Restriction (IUGR)**, the fetus is smaller than expected for gestational age, leading to a **fundal height** that measures less than the actual gestational age. - This condition is characterized by a **restricted growth rate** of the fetus, causing the uterine size to be disproportionately small. *Fibroid uterus* - The presence of **uterine fibroids** (leiomyomas) can increase the overall size of the uterus beyond what would be expected for a given gestational age. - These benign tumors add bulk to the uterine wall, leading to a **larger-than-expected uterine height**. *Wrong dates* - Incorrect estimation of the **Last Menstrual Period (LMP)** or date of conception can lead to a miscalculation of gestational age. - If the gestational age is **underestimated**, the actual uterine height will appear greater than the calculated gestational age. *Polyhydramnios* - **Polyhydramnios** is a condition characterized by an **excessive accumulation of amniotic fluid**, which distends the uterus. - Increased amniotic fluid volume leads to a significantly **larger uterine size** and a fundal height greater than the gestational age.
Question 1009: Following delivery, a tear involving the perineum and external anal sphincter with intact mucosa is classified as which grade?
- A. First degree
- B. Second degree
- C. Third degree (Correct Answer)
- D. Fourth degree
Explanation: ***Third degree*** - A third-degree perineal tear involves the **perineum** and the **external anal sphincter (EAS)**, either partially or completely, while the **anal mucosa remains intact**. - This classification is crucial for determining the necessary repair technique and predicting potential long-term complications related to **anal incontinence**. *First degree* - A first-degree tear involves only the **skin** of the perineum and the **vaginal mucosa**, without involving the underlying muscle. - These tears are typically superficial and may not even require suturing. *Second degree* - A second-degree tear involves the **perineal muscles** but does not extend to the anal sphincter. - It includes the vaginal mucosa, perineal skin, and muscles but spares the **external anal sphincter**. *Fourth degree* - A fourth-degree tear is the most severe, involving the **perineum**, **external anal sphincter**, and extending through the **anal mucosa**, exposing the rectal lumen. - These tears carry the highest risk of **fecal incontinence** and require meticulous surgical repair.