General Science - MCQ Practice Questions
General Science in SSC, railway and state exams stays at school level, which makes it one of the few sections where full marks are realistic. Practice covers physics fundamentals such as motion, light and electricity, chemistry basics including elements and compounds, and biology topics like the human body, nutrition and diseases. Answers stay at the depth the paper actually uses instead of drifting into degree level theory.
247 questions | 100% Free
Which of the following diseases is caused by the deficiency of Vitamin C?
Understanding:
We need to identify the disease caused by Vitamin C deficiency.
Step 1: Matching vitamins to deficiency diseases
Each vitamin deficiency leads to a specific disease:
Step 2: Identifying Scurvy
Scurvy is caused by a lack of Vitamin C (ascorbic acid). It is characterized by swollen and bleeding gums, weakness, anaemia, and skin haemorrhages. Vitamin C is essential for collagen synthesis, which maintains the integrity of blood vessels and connective tissue.
Answer:
The disease caused by Vitamin C deficiency is Scurvy.
Quick Tip:
A helpful mnemonic — 'C for Citrus, C for Scurvy': sailors historically suffered from scurvy due to lack of fresh fruits during long voyages.
Which of the following is the causative agent of Tuberculosis (TB)?
Understanding:
We need to identify the microorganism responsible for causing Tuberculosis.
Step 1: Identifying the causative agents of common diseases
Step 2: About Mycobacterium tuberculosis
Tuberculosis is a highly contagious airborne disease primarily affecting the lungs. It is caused by the bacterium Mycobacterium tuberculosis, discovered by Robert Koch in 1882. It spreads through respiratory droplets when an infected person coughs or sneezes.
Answer:
The causative agent of Tuberculosis is Mycobacterium tuberculosis.
Quick Tip:
Robert Koch discovered M. tuberculosis on 24 March 1882 — this date is now celebrated as World Tuberculosis Day.
Which part of the human body is affected by the disease 'Cirrhosis'?
Understanding:
We need to identify the organ affected by Cirrhosis.
Step 1: Understanding Cirrhosis
Cirrhosis is a chronic liver disease in which normal liver tissue is replaced by scar tissue (fibrosis), severely impairing liver function. Common causes include chronic alcoholism, hepatitis B and C infections, and non-alcoholic fatty liver disease.
Step 2: Ruling out other options
None of these are associated with Cirrhosis.
Answer:
Cirrhosis is a disease that affects the Liver.
Quick Tip:
Cirrhosis is an irreversible condition — the scarred liver tissue cannot regenerate, making early diagnosis and lifestyle changes critical.
The disease 'Dengue' is transmitted by which of the following mosquitoes?
Understanding:
We need to identify the mosquito species that transmits Dengue fever.
Step 1: Mapping mosquito species to diseases
Step 2: About Dengue transmission
Dengue is a viral disease caused by the Dengue virus (DENV), which belongs to the Flavivirus genus. It is spread primarily by the female Aedes aegypti mosquito, which typically bites during the day. Dengue is characterised by high fever, severe headache, pain behind the eyes, joint and muscle pain, and rash.
Answer:
Dengue is transmitted by the Aedes aegypti mosquito.
Quick Tip:
Aedes aegypti mosquitoes breed in stagnant, clean water stored in containers, flower pots, and tyres — eliminating such breeding sites is the primary prevention strategy.
Which of the following diseases is NOT caused by a virus?
Understanding:
We need to identify the disease among the given options that is not caused by a virus.
Step 1: Classifying the diseases by causative agents
Step 2: Identifying the non-viral disease
Cholera is a bacterial infection caused by Vibrio cholerae. It spreads through contaminated water and food, causing severe watery diarrhoea and dehydration. The other three diseases in the list are all caused by viruses.
Answer:
Cholera is the disease that is NOT caused by a virus — it is caused by the bacterium Vibrio cholerae.
Quick Tip:
Cholera is a water-borne disease — the key prevention strategy is access to clean drinking water and proper sanitation, not vaccination (unlike the other viral diseases listed).
Which of the following hormones is directly responsible for regulating blood sugar levels in the human body?
Understanding:
We need to identify the hormone primarily responsible for regulating blood glucose (sugar) levels.
Step 1: Role of each hormone
Step 2: Why Insulin is correct
Insulin is the primary hormone that regulates blood glucose. When blood sugar rises after a meal, the pancreas secretes insulin, which facilitates the uptake of glucose by body cells and its storage as glycogen in the liver. Deficiency or resistance to insulin leads to Diabetes Mellitus.
Answer:
Insulin is the hormone directly responsible for regulating blood sugar levels.
Quick Tip:
Insulin lowers blood sugar (anabolic), while Glucagon (also from the pancreas) raises blood sugar — they act as antagonists to maintain glucose homeostasis.
BCG vaccine, used to provide protection against Tuberculosis, stands for which of the following?
Understanding:
We need to identify the full form of the BCG vaccine used against Tuberculosis.
Step 1: Historical background of BCG
The BCG vaccine was developed by French bacteriologists Albert Calmette and Camille Guérin at the Pasteur Institute. They created a weakened (attenuated) strain of Mycobacterium bovis to develop immunity against Tuberculosis.
Step 2: Full form
BCG stands for Bacillus Calmette-Guérin, named after its two developers. It is one of the oldest and most widely used vaccines in the world and is part of India's Universal Immunisation Programme (UIP), given to newborns.
Answer:
BCG stands for Bacillus Calmette-Guérin.
Quick Tip:
The BCG vaccine was first used in humans in 1921. In India, it is administered at birth as part of the national immunisation schedule to protect against severe forms of TB in children.
Which of the following diseases is caused by the protozoan Plasmodium vivax?
Understanding:
We need to identify the disease caused by the protozoan Plasmodium vivax.
Step 1: Mapping protozoans to diseases
Step 2: About Plasmodium vivax and Malaria
Plasmodium vivax is one of four species of Plasmodium that causes malaria in humans (others: P. falciparum, P. malariae, P. ovale). It causes Benign Tertian Malaria, where fever recurs every 48 hours. Malaria is transmitted by the bite of the female Anopheles mosquito.
Answer:
Malaria is the disease caused by the protozoan Plasmodium vivax.
Quick Tip:
Among the Plasmodium species, P. falciparum causes the most severe and potentially fatal form of malaria — Malignant Tertian Malaria — and is responsible for the majority of malaria deaths globally.
Haemophilia is a disease related to which of the following conditions?
Understanding:
We need to identify what Haemophilia is and how it affects the body.
Step 1: Understanding Haemophilia
Haemophilia is a hereditary (genetic) bleeding disorder in which the blood does not clot properly. It occurs due to the deficiency or dysfunction of specific clotting factors — Factor VIII in Haemophilia A (most common) and Factor IX in Haemophilia B. As a result, even minor injuries can lead to prolonged bleeding.
Step 2: Ruling out other options
Step 3: Genetic nature
Haemophilia is an X-linked recessive disorder. It predominantly affects males, while females are usually carriers. The gene responsible for the clotting factors is located on the X chromosome.
Answer:
Haemophilia is characterised by the inability of blood to clot normally due to deficiency of clotting factors.
Quick Tip:
Haemophilia is often called the 'Royal Disease' because it spread through the royal families of Europe, descended from Queen Victoria, who was a carrier.
Which of the following vitamins is synthesised in the human skin upon exposure to sunlight?
Understanding:
We need to identify which vitamin is produced in the human skin when it is exposed to sunlight.
Step 1: The process of Vitamin D synthesis
When ultraviolet B (UVB) radiation from sunlight falls on the skin, it converts a cholesterol derivative (7-dehydrocholesterol) present in the skin into Vitamin D3 (cholecalciferol). This is then processed by the liver and kidneys into its active hormonal form, calcitriol.
Step 2: Role of Vitamin D
Vitamin D is essential for the absorption of calcium and phosphorus in the intestine, which is critical for bone mineralisation and strength. Deficiency of Vitamin D leads to Rickets in children and Osteomalacia in adults.
Step 3: Why other vitamins are incorrect
Answer:
Vitamin D is the vitamin synthesised in the human skin upon exposure to sunlight.
Quick Tip:
Vitamin D is unique in that it functions both as a vitamin (obtained from diet) and as a hormone (synthesised by the body). It is the only vitamin the body can produce on its own from non-food sources.