NEET-PG 2015 Practice Questions

Q: Pupillary reflex pathway - All of the following are a part except?

Medial geniculate body. ***Medial geniculate body*** - The **medial geniculate body** is part of the **auditory pathway**, involved in processing sound information [2]. - It does not play a role in the **afferent** or **efferent** limbs of the pupillary light reflex. *Edinger Westphal nucleus* - The **Edinger-Westphal nucleus** is the **parasympathetic nucleus** of cranial nerve III (**oculomotor nerve**) [1]. - It provides preganglionic parasympathetic fibers that lead to pupillary constriction via the **ciliary ganglion** [1]. *Pretectal nuclei* - The **pretectal nuclei** receive input from the **retina** and are critical for the **afferent limb** of the pupillary light reflex [1], [3]. - They send fibers to the **Edinger-Westphal nuclei** bilaterally, mediating the direct and consensual light reflexes [1]. *Retinal ganglion cell* - **Retinal ganglion cells** are responsible for transmitting visual information from the **retina** to the brain [4]. - A subset of these cells, containing **melanopsin**, are photosensitive and specifically mediate the input for the **pupillary light reflex** [3].

Q: The zonules suspending the lens are attached to the?

Ciliary body. ***Ciliary body*** - The **suspensory ligaments of the lens**, also known as zonules of Zinn, connect the **lens capsule** to the **ciliary body**. - These zonules play a crucial role in **accommodation** by transmitting forces from the ciliary muscle to alter the shape of the lens. *Root of iris* - The **root of the iris** attaches the iris to the ciliary body but does not directly connect to the lens zonules. - The iris primarily controls the **pupil size** and light entry, while the zonules are involved in lens suspension and focusing. *Anterior vitreous* - The **anterior vitreous** is the part of the vitreous humor located in front of the lens. - While it is in close proximity to the lens, the zonules do not directly attach to the vitreous but rather to the ciliary body. *Limbus* - The **limbus** is the transitional zone between the cornea and the sclera, the white outer layer of the eye. - It is an important anatomical landmark for eye surgery and drainage of aqueous humor, but it has no direct role in suspending the lens.

Q: What is the most important criterion in a causal relationship hypothesis?

Temporal association. ***Temporal association*** - This is the **sine qua non** of causality, meaning the exposure or cause must always precede the outcome or effect in time. - Without the exposure occurring before the disease, a causal link cannot be established, even if other criteria are met. *Coherence of association* - This refers to the consistency of findings with current scientific knowledge and **biological plausibility**. - While important for supporting causality, a coherent explanation is not sufficient in itself to prove causation and may even be misleading if current knowledge is incomplete. *Specificity of association* - This criterion suggests that a single exposure should lead to a single outcome, or a single outcome should be caused by a single exposure. - However, many diseases have **multiple causes**, and many exposures can lead to multiple effects, making this a weak criterion in modern epidemiology. *Strength of association* - A **strong association**, often measured by a high relative risk or odds ratio, makes a causal relationship more likely but does not guarantee it. - Strong associations can still be due to **confounding factors** or bias, and weak associations can be causal.

Q: What is the caloric requirement for an adult male engaged in heavy physical work?

3500 kcal/d. ***3500 kcal/d*** - Adult males engaged in **heavy physical work** have significantly higher energy demands due to increased **metabolic expenditure**. - This level of caloric intake is necessary to support physical activity, maintain muscle mass, and prevent weight loss in individuals with demanding occupations. *2000 kcal/d* - This caloric intake is typically recommended for adult females who are **sedentary** or for adult males engaging in light activity, which is insufficient for heavy physical work. - It would likely lead to a **caloric deficit** and weight loss for an individual performing heavy labor. *2500 kcal/d* - This level of intake is more appropriate for moderately active adult males, but it would often be **insufficient** for those performing heavy physical work. - Individuals engaged in heavy labor require additional energy to fuel their intense activities to maintain **energy balance**. *3000 kcal/d* - While a higher intake, 3000 kcal/d might still be **borderline** or insufficient for an adult male engaged in very heavy or sustained physical work. - This value might be appropriate for moderately heavy work, but heavy work often necessitates an even higher **caloric intake** to meet energy demands.

Q: Skin fold thickness is measured in all of the following places, EXCEPT:

Suprapubic. ***Suprapubic*** - The **suprapubic** region is not a standard site for measuring **skinfold thickness** in body composition assessment. - Skinfold measurements are typically taken from areas with subcutaneous fat that are easily accessible and standardized. *Mid triceps* - The **mid-triceps** is a common and important site for measuring skinfold thickness due to its relatively consistent subcutaneous fat distribution. - It is used to estimate total body fat and is a good indicator of **nutritional status**. *Biceps* - The **biceps** region is also a recognized site for skinfold thickness measurements, providing data on upper arm subcutaneous fat. - It is often measured alongside the triceps to give a more comprehensive picture of fat distribution in the arm. *Suprailiac* - The **suprailiac** region, located just above the iliac crest, is a standard site for skinfold measurements. - This site is particularly useful for assessing abdominal fat and is included in many body composition models.

Q: Silk retina is seen in ?

Retinal detachment. ***Retinal detachment*** - **"Silk retina" or "silky sheen"** is a classic ophthalmoscopic finding in retinal detachment, describing the **smooth, glistening appearance** of the detached sensory retina. - The detached retina appears **elevated, gray, and translucent** with characteristic folds or undulations, exhibiting a **satiny or silky luster** when examined. - Patients typically present with **photopsias (flashes of light)**, **floaters**, and progressive **visual field defect** described as a "curtain" or "shadow." - This is a true **ophthalmic emergency** requiring urgent surgical intervention. *Diabetic retinopathy* - Characterized by **microaneurysms, dot-blot hemorrhages, hard exudates**, and **cotton-wool spots** in non-proliferative stages. - Proliferative diabetic retinopathy shows **neovascularization** and vitreous hemorrhage. - Does not produce the "silk retina" appearance. *Macular degeneration* - Age-related macular degeneration presents with **drusen, pigmentary changes**, and in advanced stages, **geographic atrophy** or **choroidal neovascularization**. - May show a **"beaten-bronze" appearance** in certain macular dystrophies (Best's disease), but not "silk retina." - Central vision loss is the predominant symptom. *Hypertensive retinopathy* - Features include **generalized arteriolar narrowing, AV nicking, flame-shaped hemorrhages**, and **cotton-wool spots**. - In severe cases (Grade IV), **optic disc edema** and macular star exudates may occur. - Vascular changes dominate the clinical picture, not a silky retinal appearance.

Q: Which of the following statements is false regarding Eale's disease?

Optic neuritis. ***Correct Answer: Optic neuritis*** - This statement is **false** because **Eale's disease** is a **peripheral retinal vasculitis** (periphlebitis) that primarily affects the **peripheral retinal veins**. - The condition does **NOT involve the optic nerve**, and **optic neuritis is NOT a recognized feature or complication** of Eale's disease. - The disease process is confined to the retinal vasculature and does not extend anteriorly to involve the optic disc or nerve in typical cases. *AKT is given* - While the exact etiology of Eale's disease remains uncertain, there is a **historical and clinical association with tuberculosis**, particularly in TB-endemic regions like India. - In clinical practice, **anti-tubercular therapy (ATT/AKT) is often empirically administered** when TB cannot be ruled out or when there is suspicion of systemic TB. - Some studies suggest ATT may help reduce inflammation and prevent recurrence in selected cases. *Vitreous Hemorrhage* - This is a **hallmark complication** of Eale's disease, particularly in stage 3 (proliferative stage). - **Recurrent vitreous hemorrhage** occurs due to rupture of fragile neovascular vessels that form in response to retinal ischemia. - It is one of the most common presentations requiring intervention. *Retinal detachment may occur* - **Tractional retinal detachment** is a recognized complication resulting from contraction of **fibrovascular proliferative membranes**. - **Rhegmatogenous retinal detachment** can also occur if vitreoretinal traction causes retinal breaks. - Both types may require surgical intervention (vitrectomy).

Q: What is the average survival time of a person without food and water under normal conditions?

3 to 5 days. ***3 to 5 days*** - When deprived of **both food and water**, the human body can typically survive for **3 to 5 days** under normal conditions. - **Water is the critical limiting factor** - while the body can tolerate food deprivation for weeks, lack of water becomes life-threatening within days. - Water is essential for cellular metabolism, temperature regulation, waste elimination, and cardiovascular function. *1 to 3 days* - This represents the **absolute minimum survival time** without water, particularly under harsh environmental conditions (heat, physical exertion, humidity). - However, under normal/average conditions, most individuals can survive slightly longer than this range. *10 to 12 days* - This duration is **not possible** without water, even with optimal conditions. - This timeframe is more consistent with survival **without food but WITH water**, which can extend to 3-4 weeks or more. *5 to 10 days* - While exceptional cases might approach 5-7 days without water in cool, resting conditions with low metabolic demands, **10 days is physiologically implausible**. - Severe dehydration typically causes death by day 5-7 maximum, with most succumbing earlier.

Question 1

Pupillary reflex pathway - All of the following are a part except?

Accepted Answer

Medial geniculate body

Answer

Edinger Westphal nucleus

Answer

Pretectal nuclei

Answer

Retinal ganglion cell

Question 2

The zonules suspending the lens are attached to the?

Accepted Answer

Ciliary body

Answer

Root of iris

Answer

Anterior vitreous

Answer

Limbus

Question 3

What is the most important criterion in a causal relationship hypothesis?

Accepted Answer

Temporal association

Answer

Coherence of association

Answer

Specificity of association

Answer

Strength of association

Question 4

What is the caloric requirement for an adult male engaged in heavy physical work?

Accepted Answer

3500 kcal/d

Answer

2000 kcal/d

Answer

2500 kcal/d

Answer

3000 kcal/d

Question 5

What is the definition of a reservoir in the context of infectious diseases?

Accepted Answer

Person, animal or substance in which infectious agent lives and multiplies

Answer

Person, animal or object from which infectious agent is transmitted to host

Answer

Person or animal in which infectious agent causes a disease

Answer

Person or animal that transmits the infectious agent mechanically

Question 6

Skin fold thickness is measured in all of the following places, EXCEPT:

Accepted Answer

Suprapubic

Answer

Mid triceps

Answer

Biceps

Answer

Suprailiac

Question 7

Silk retina is seen in ?

Accepted Answer

Retinal detachment

Answer

Diabetic retinopathy

Answer

Macular degeneration

Answer

Hypertensive retinopathy

Question 8

Astigmatism is defined as?

Accepted Answer

Refractive error wherein refraction varies along different meridians

Answer

Refractive error due to long AP length of eyeball

Answer

Varying refractive error in both eyes

Answer

Varying shape perception by both eyes

Question 9

Which of the following statements is false regarding Eale's disease?

Accepted Answer

Optic neuritis

Answer

AKT is given

Answer

Vitreous Hemorrhage

Answer

Retinal detachment may occur

Question 10

What is the average survival time of a person without food and water under normal conditions?

Accepted Answer

3 to 5 days

Answer

10 to 12 days

Answer

1 to 3 days

Answer

5 to 10 days

NEET-PG 2015

Anatomy

Community Medicine

Ophthalmology

Physiology