About this quiz
Basic biology and health facts covering human organs, bones, blood groups, vitamins, cells, photosynthesis and common diseases.
This Lok Sewa practice set has 20 multiple-choice questions (Subject: General Knowledge · For: Kharidar, Nayab Subba · Level: Easy). Take the quiz above first; after that, use the study list below to revise every question with its correct answer and a short explanation.
Study list: all 20 questions with answers and explanations
How many bones are there in the body of an adult human?
- A) 186
- B) 206 ✔
- C) 226
- D) 300
Why: An adult human skeleton has 206 bones; newborns have more, which fuse as they grow.
Which is the largest organ of the human body?
- A) Liver
- B) Brain
- C) Lungs
- D) Skin ✔
Why: The skin is the largest organ of the human body by surface area and weight.
Which is the largest gland in the human body?
- A) Liver ✔
- B) Pancreas
- C) Thyroid
- D) Pituitary
Why: The liver is the largest gland in the human body.
Which is the longest bone in the human body?
- A) Tibia
- B) Humerus
- C) Femur ✔
- D) Fibula
Why: The femur, or thigh bone, is the longest and strongest bone in the human body.
Which is the smallest bone in the human body?
- A) Incus
- B) Malleus
- C) Stapes ✔
- D) Phalanx
Why: The stapes, one of the three tiny bones in the middle ear, is the smallest bone in the body.
How many chambers does the human heart have?
- A) Four ✔
- B) Two
- C) Three
- D) Five
Why: The human heart has four chambers: two atria and two ventricles.
Which organ produces the hormone insulin?
- A) Liver
- B) Kidney
- C) Thyroid gland
- D) Pancreas ✔
Why: Insulin is produced by the beta cells of the islets of Langerhans in the pancreas.
Which blood group is known as the universal donor?
- A) AB positive
- B) O negative ✔
- C) A positive
- D) B negative
Why: O negative red blood cells have no A, B or Rh antigens, so they can be given to patients of any blood group.
Which blood group is known as the universal recipient?
- A) AB positive ✔
- B) O negative
- C) A negative
- D) B positive
Why: People with AB positive blood can receive red cells from all ABO and Rh types.
Who discovered the ABO blood group system?
- A) Louis Pasteur
- B) Alexander Fleming
- C) Karl Landsteiner ✔
- D) Robert Koch
Why: Karl Landsteiner discovered the ABO blood groups in 1901 and later received the Nobel Prize.
Deficiency of which vitamin causes scurvy?
- A) Vitamin A
- B) Vitamin C ✔
- C) Vitamin D
- D) Vitamin K
Why: Scurvy, with bleeding gums and weakness, is caused by a lack of vitamin C.
Deficiency of which vitamin causes rickets in children?
- A) Vitamin B1
- B) Vitamin C
- C) Vitamin E
- D) Vitamin D ✔
Why: Lack of vitamin D leads to rickets, in which bones become soft and weak.
Night blindness is caused by deficiency of which vitamin?
- A) Vitamin B12
- B) Vitamin K
- C) Vitamin C
- D) Vitamin A ✔
Why: Vitamin A is needed for vision in dim light, so its deficiency causes night blindness.
Beriberi is caused by deficiency of which vitamin?
- A) Vitamin B12
- B) Vitamin B1 (thiamine) ✔
- C) Vitamin D
- D) Vitamin C
Why: Beriberi results from a lack of vitamin B1, also called thiamine.
Which part of the cell is called the powerhouse of the cell?
- A) Nucleus
- B) Ribosome
- C) Mitochondria ✔
- D) Golgi apparatus
Why: Mitochondria produce most of the cell's energy in the form of ATP.
Which green pigment in plant leaves captures sunlight for photosynthesis?
- A) Chlorophyll ✔
- B) Haemoglobin
- C) Melanin
- D) Bilirubin
Why: Chlorophyll, the green pigment in chloroplasts, captures light energy for photosynthesis.
Which gas is released by green plants during photosynthesis?
- A) Carbon dioxide
- B) Nitrogen
- C) Oxygen ✔
- D) Hydrogen
Why: During photosynthesis plants take in carbon dioxide and water and release oxygen.
Malaria is spread to humans by the bite of which mosquito?
- A) Female Anopheles ✔
- B) Male Anopheles
- C) Aedes
- D) Culex
Why: Malaria is caused by the Plasmodium parasite, which is transmitted by the bite of an infected female Anopheles mosquito.
Tuberculosis is caused by which type of organism?
- A) Virus
- B) Bacterium ✔
- C) Fungus
- D) Protozoan
Why: Tuberculosis is caused by the bacterium Mycobacterium tuberculosis.
Deficiency of which mineral in the diet causes goitre?
- A) Iron
- B) Calcium
- C) Sodium
- D) Iodine ✔
Why: Lack of iodine causes enlargement of the thyroid gland, known as goitre; iodised salt helps prevent it.