General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
1
Which imaging modality is most accurate for measuring the 'Ejection Fraction' (EF) of the heart?
Answer:
Echocardiogram
While Cardiac MRI is the most precise (reference standard), the Echocardiogram is the most widely used and accurate clinical tool for assessing LV function and calculating the Ejection Fraction.
2
Which diagnostic marker is used to monitor for recurrence of 'Colorectal Cancer' after surgery?
Answer:
Carcinoembryonic Antigen (CEA)
CEA is not sensitive enough for initial screening, but it is highly useful for monitoring treatment response and detecting early recurrence in patients previously diagnosed with colorectal cancer.
3
Which condition is diagnosed using 'Spirometry' and shows an improvement after bronchodilator use?
Answer:
Asthma
Reversibility of airflow obstruction (an increase in FEV1 of >12% and >200mL after inhaling a bronchodilator) is a key diagnostic feature that distinguishes Asthma from COPD.
4
Which laboratory test is most useful for diagnosing 'Primary Hyperparathyroidism'?
Answer:
High Calcium and High (or inappropriately normal) PTH
In primary hyperparathyroidism, the parathyroid gland secretes too much PTH regardless of calcium levels. This leads to elevated serum calcium, which should normally suppress PTH production.
5
A 'Positive Pathergy Test' is a diagnostic criterion for which systemic disease?
Answer:
Behçet's Disease
The pathergy test involves pricking the skin with a sterile needle. If a small bump or pustule forms within 48 hours, it indicates skin hyperreactivity, which is characteristic of Behçet's disease.
6
Which diagnostic test uses a radioactive tracer to detect 'hot' or 'cold' nodules in the thyroid?
Answer:
Radioactive Iodine Uptake (RAIU) and Scan
A thyroid scan helps determine the function of a nodule. 'Cold' nodules do not take up iodine and have a higher risk of being malignant, whereas 'hot' nodules are usually hyperfunctioning and benign.
7
Which physical finding is characterized by bruising over the 'mastoid process', indicating a basal skull fracture?
Answer:
Battle's Sign
Battle's sign is an indication of a fracture of the posterior cranial fossa. It typically takes 24–48 hours to appear after the initial head trauma.
8
What is the primary diagnostic finding in the joints of a patient with 'Pseudogout'?
Answer:
Calcium Pyrophosphate Dihydrate (CPPD) Crystals
Unlike Gout (uric acid), Pseudogout is caused by the deposition of CPPD crystals. These crystals appear positively birefringent and rhomboid-shaped under polarized light microscopy.
9
Which blood test is the most sensitive screening tool for 'Hypothyroidism'?
Answer:
Serum TSH
The pituitary gland is extremely sensitive to small changes in thyroid hormone levels. Therefore, an elevated TSH is the most sensitive and earliest indicator of primary hypothyroidism.
10
In the diagnosis of 'Wilson's Disease', what is the classic finding on an eye exam?
Answer:
Kayser-Fleischer rings
Kayser-Fleischer rings are brownish-yellow deposits of copper in the cornea (Descemet's membrane). They are a hallmark of Wilson's disease, a disorder of copper metabolism.