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
111
Elements in the same period have the same number of:
Answer:
Electron shells
All elements in a period have their valence electrons in the same principal energy level (shell). For example, all Period 3 elements have electrons in the 1st, 2nd, and 3rd shells.
112
A vaccine traditionally contains which of the following to stimulate an immune response?
Answer:
Weakened (attenuated) or killed pathogens
Vaccines introduce weakened, dead, or specific parts (antigens) of a pathogen into the body. This is enough to trigger the immune system to recognize the 'invader' and produce antibodies and memory cells without causing the actual disease in the person.
113
Which of the following describes an isotope?
Answer:
Atoms with the same atomic number but different mass numbers
Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons.
114
Which element is commonly used as the reference for the Pauling scale of electronegativity?
Answer:
Fluorine
Fluorine is the most electronegative element and is assigned the highest value of 4.0 on the Pauling scale, serving as the benchmark for comparing other elements.
115
Which of the following terms refers to any microorganism that has the capability to cause a disease in its host?
Answer:
Pathogen
A pathogen is a biological agent that causes disease or illness to its host. While many microorganisms are harmless or even beneficial to humans, pathogens have evolved specific mechanisms to invade the body, evade the immune system, and disrupt normal physiological functions.
116
Which of the following diseases is spread by the 'Aedes aegypti' mosquito?
Answer:
Dengue Fever
While the Anopheles mosquito transmits Malaria, the Aedes aegypti mosquito is the primary vector for viruses that cause Dengue Fever, Zika, and Yellow Fever. These mosquitoes typically bite during the day.
117
Some people are allergic to 'Penicillin'. What happens in their body during an allergic reaction?
Answer:
The immune system overreacts to the drug, treating it as a dangerous invader
In an allergy, the immune system mistakenly identifies a harmless substance (like an antibiotic) as a threat. This triggers the release of histamines and other chemicals, leading to symptoms like hives, swelling, or in severe cases, anaphylaxis.
118
Which subatomic particle was discovered using the cathode ray tube?
Answer:
Electron
J.J. Thomson used cathode ray tubes to show that rays emitted from the cathode were made of negatively charged particles, which he called 'corpuscles,' later known as electrons.
119
Which of the following is a potential future solution to the 'Antibiotic Crisis' of rising resistance?
Answer:
Phage therapy (using viruses that kill bacteria) and the discovery of new drug classes
Scientists are looking for alternatives to traditional antibiotics. Phage therapy uses bacteriophages (viruses that specifically target and kill bacteria). They are also exploring the deep ocean and soil for new natural compounds that bacteria haven't seen before.
120
What is the main function of 'Antiseptics'?
Answer:
To kill or inhibit the growth of microorganisms on living tissue
Antiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection. Examples include rubbing alcohol or iodine used on a cut. Disinfectants are similar but are too harsh for skin and are used on objects.