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
131
What does the term 'asymptomatic carrier' mean in the context of infectious diseases?
Answer:
A person who is infected but shows no symptoms of the disease
An asymptomatic carrier is an individual who carries a pathogen and can transmit it to others but does not experience any symptoms themselves. This makes them 'silent' spreaders, as neither they nor those around them realize they are infected.
132
Which group of elements is known as 'Chalcogens'?
Answer:
Group 16
Group 16 elements (Oxygen, Sulfur, etc.) are called chalcogens, a name derived from the Greek word for 'ore-former', as many ores are oxides or sulfides.
133
Elements in Group 18 of the Periodic Table are known as:
Answer:
Noble Gases
Noble gases are characterized by having a completely filled valence shell ($ns^2 np^6$, except Helium). This stable electron configuration makes them chemically inert under standard conditions.
134
Which element in the third period has the highest first ionization energy?
Answer:
Argon
Argon, being a noble gas with a stable octet, requires the most energy to remove an electron. Generally, noble gases have the highest ionization energies in their respective periods.
135
Which mode of transmission is responsible for spreading the Human Immunodeficiency Virus (HIV)?
Answer:
Exchange of infected body fluids
HIV is transmitted through specific body fluids, including blood, semen, vaginal fluids, and breast milk. Common routes include unprotected sexual contact, sharing contaminated needles, or from mother to child during childbirth or breastfeeding.
136
Which shell has the highest energy in an atom of Aluminum (Atomic No. 13)?
Answer:
M shell
The electron configuration of Aluminum is $2, 8, 3$. The electrons occupy the K ($n=1$), L ($n=2$), and M ($n=3$) shells. Since energy increases with the distance from the nucleus, the M shell has the highest energy.
137
Brownian motion provides evidence for:
Answer:
The existence of atoms and molecules in constant motion
Brownian motion is the random movement of particles suspended in a fluid resulting from their bombardment by fast-moving atoms or molecules in the gas or liquid.
138
Ringworm is a common skin infection characterized by a red, itchy, circular rash. What type of pathogen causes this condition?
Answer:
Fungus
Despite its name, ringworm is not caused by a worm; it is a fungal infection of the skin. Fungi called dermatophytes thrive on keratin, a protein found in skin, hair, and nails, leading to the characteristic circular lesions.
139
Which of the following describes a 'cation'?
Answer:
A positively charged ion
A cation is formed when an atom loses electrons (negative charge), resulting in more protons than electrons and a net positive charge.
140
Which microorganism causes 'Oral Thrush', a condition where white patches appear on the tongue and mouth?
Answer:
A fungus (yeast) called Candida
Oral thrush is a yeast infection caused by the fungus Candida albicans. While Candida is normally present in the mouth in small amounts, it can overgrow if the immune system is weakened or if the balance of 'good' bacteria is disrupted by antibiotics.