Top 20 Biology MCQs for Competitive Exams

பல்வேறு போட்டித் தேர்வுகளில் உயிரியல் முக்கியப் பங்காற்றுகிறது, விண்ணப்பதாரர்களுக்கு அவர்களின் தயாரிப்பில் உதவ, நாங்கள் 30 கேள்விகளை (MCQs) தொகுத்துள்ளோம். உங்கள் உயிரியல் அறிவை மேம்படுத்துவதற்கும், வரவிருக்கும் தேர்வுகளுக்கு உங்களை சிறப்பாக தயார்படுத்துவதற்கும் ஒவ்வொரு கேள்விக்கும் சரியான பதில் உள்ளது.

Q1. Which of the following diseases is caused by a bacterial infection?

(a) Influenza

(b) Malaria

(d) Diabetes

Q2. Which of the following diseases is caused by a virus?

(a) Asthma

(b) Hepatitis

(d) Osteoporosis

Q3. Which disease is characterized by high blood sugar levels?

(a) Hypertension

(b) Arthritis

(d) Anemia

Q4. Which disease is caused by a deficiency of vitamin C?

(a) Scurvy

(b) Rickets

(d) Tuberculosis

Q5. Which disease is transmitted through the bite of an infected mosquito?

(a) Dengue fever

(b) Pneumonia

(d) Diabetes mellitus

Q6. Which of the following diseases is caused by the Plasmodium parasite transmitted through the bite of infected mosquitoes?

(a) Dengue fever

(b) Chikungunya

(d) Zika virus

Q7. Which disease is characterized by the inflammation of the airways and difficulty in breathing?

(a) Arthritis

(b) Asthma

(d) Tuberculosis

Q8. Which disease is characterized by abnormal cell growth and the potential to invade or spread to other parts of the body?

(a) Malaria

(b) Arthritis

(d) Diabetes mellitus

Q9. Which disease is caused by the deficiency of iron in the body?

(a) Diabetes mellitus

(b) Scurvy

(d) Tuberculosis

Q10. Which of the following diseases is characterized by the progressive degeneration of nerve cells in the brain?

(a) Alzheimer’s disease

(b) Parkinson’s disease

(d) Epilepsy

Q11. Which vitamin is essential for maintaining healthy eyesight?

(a) Vitamin A

(b) Vitamin C

(d) Vitamin K

Q12. Which vitamin is essential for collagen synthesis and wound healing?

(a) Vitamin A

(b) Vitamin C

(d) Vitamin K

Q13. Which mineral is necessary for the production of hemoglobin in red blood cells?

(a) Iron

(b) Calcium

(d) Iodine

Q14. Which of the following vitamins must be obtained from external sources as our body cannot produce them?

(a) vitamin A

(b) vitamin K

(d) All of the above

Q15. Which mineral is important for proper nerve function and muscle contraction?

(a) Iron

(b) Calcium

(d) Potassium

Q16. How many essential vitamins are required for the proper functioning of the human body?

(a) 13

(b) 16

(d) 22

Q17. Which of the following vitamins are classified as fat-soluble vitamins?

(a) Vitamin B and Vitamin B12

(b) Vitamin C and Vitamin B

(d) Vitamin B6 and Vitamin C

Q18. Which vitamin is necessary for blood clotting?

(a) Vitamin A

(b) Vitamin C

(d) Vitamin K

Q19. Which mineral is necessary for the proper functioning of the thyroid gland?

(a) Iron

(b) Calcium

(d) Iodine

Q20. Which mineral is a component of many enzymes and is involved in energy metabolism?

(a) Potassium

(b) Calcium

(d) Magnesium

SOLUTIONS

S1. Ans.(c)

Sol. Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis bacteria.

Disease	Cause	Associated Bacteria/Virus
Influenza	Viral infection	Influenza viruses (e.g., Influenza A, B, C viruses)
Malaria	Parasitic infection	Plasmodium parasites (e.g., Plasmodium falciparum, Plasmodium vivax)
Tuberculosis	Bacterial infection	Mycobacterium tuberculosis
Diabetes	High blood sugar	Insulin not properly released by pancreas

S2. Ans.(b)

Sol. Hepatitis is a disease caused by viral infections that specifically affect the liver. There are several types of viral hepatitis, including hepatitis A, hepatitis B, hepatitis C, hepatitis D, and hepatitis E. These viruses can cause inflammation of the liver, leading to a range of symptoms and potential long-term liver damage.

Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways. It is triggered by environmental factors such as allergens or irritants.
Leukemia is a type of cancer that affects the blood and bone marrow, resulting in abnormal production of white blood cells.
Osteoporosis is a condition characterized by weakened and brittle bones, usually associated with aging or hormonal imbalances.

S3. Ans.(c)

Sol. Diabetes mellitus is a disease characterized by high blood sugar levels, also known as hyperglycemia. It occurs when the body either doesn’t produce enough insulin or cannot effectively use the insulin it produces. Insulin is a hormone that regulates blood sugar levels and allows cells to utilize glucose for energy.

Hypertension is a condition characterized by high blood pressure. While diabetes can be a risk factor for hypertension, they are separate conditions.
Arthritis refers to inflammation of the joints and can have various causes.
Anemia is a condition characterized by a deficiency of red blood cells or hemoglobin, which impairs the ability of the blood to carry oxygen.

S4. Ans.(a)

Sol. Scurvy is a disease that is caused by a deficiency of vitamin C (ascorbic acid).

Vitamin C plays a crucial role in the synthesis of collagen, a protein important for the health of connective tissues, blood vessels, and bones. Without adequate vitamin C, the body is unable to produce or maintain healthy collagen, leading to various symptoms associated with scurvy.
Rickets is a disease caused by vitamin D, calcium, or phosphate deficiency, leading to impaired bone development and weak or deformed bones.
Malaria is a parasitic infection caused by the bite of infected mosquitoes.
Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis and is not directly associated with vitamin deficiencies.

S5. Ans.(a)

Sol. Dengue fever is a viral disease that is primarily transmitted through the bite of infected mosquitoes, particularly the Aedes aegypti mosquito. The virus responsible for dengue fever belongs to the Flaviviridae family.

Pneumonia is a respiratory infection caused by bacteria, viruses, or fungi.

Osteoporosis is a condition characterized by weakened and brittle bones.

Diabetes mellitus is a metabolic disorder characterized by high blood sugar levels.

S6. Ans.(c)

Sol. Malaria is a disease caused by the Plasmodium parasite, which is transmitted to humans through the bite of infected female Anopheles mosquitoes. It is characterized by recurrent fever, chills, and flu-like symptoms.

Dengue fever and Chikungunya are viral diseases transmitted by infected mosquitoes.
The Zika virus is another viral disease transmitted by mosquitoes, specifically the Aedes mosquito. It is not caused by the Plasmodium parasite and is associated with neurological complications and birth defects in newborns.

S7. Ans.(b)

Sol. Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways, leading to difficulty breathing. It is typically associated with symptoms such as wheezing, coughing, chest tightness, and shortness of breath.

Arthritis refers to inflammation of the joints.
Osteoporosis is a condition characterized by weakened and brittle bones.
Tuberculosis is a bacterial infection primarily affecting the lungs and can cause symptoms such as cough, chest pain, and shortness of breath.

S8. Ans.(c)

Sol. Cancer is a disease characterized by the abnormal and uncontrolled growth of cells. These cells have the potential to invade nearby tissues and can also spread to other parts of the body through a process called metastasis. Cancer can affect various organs and tissues in the body, and there are numerous types of cancer, including breast cancer, lung cancer, prostate cancer, and leukemia, among others.

Malaria is a parasitic infection transmitted through the bite of infected mosquitoes and is not related to abnormal cell growth.
Arthritis refers to inflammation of the joints
Diabetes mellitus is a metabolic disorder characterized by high blood sugar levels.

S9. Ans.(c)

Sol. Anemia is a condition caused by a deficiency of iron in the body. Iron is an essential nutrient required for the production of hemoglobin, a protein in red blood cells that carries oxygen to tissues throughout the body.

Diabetes mellitus is a metabolic disorder characterized by high blood sugar levels.
Scurvy is a disease caused by a deficiency of vitamin C, not iron.
Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis.

S10. Ans.(a)

Sol. Alzheimer’s disease is a neurodegenerative disorder characterized by the progressive degeneration and loss of nerve cells (neurons) in the brain. This degeneration primarily affects regions of the brain involved in memory, thinking, and behavior, leading to cognitive decline and memory loss.

Parkinson’s disease is another neurodegenerative disorder characterized by the degeneration of dopamine-producing neurons in the brain, which leads to motor symptoms such as tremors, rigidity, and difficulty with movement.
Multiple sclerosis is an autoimmune disease in which the immune system mistakenly attacks the protective covering of nerve fibers, resulting in communication problems between the brain and the rest of the body. It can lead to a wide range of symptoms depending on which nerves are affected.
Epilepsy is a neurological disorder characterized by recurrent seizures, which are caused by abnormal electrical activity in the brain.

S11. Ans.(a)

Sol. Vitamin A is essential for maintaining healthy eyesight. It plays a vital role in the functioning of the retina and helps prevent night blindness and other vision-related issues.

Vitamin A can be found in foods such as liver, fish oil, egg yolks, dairy products (milk, cheese, butter), carrots, sweet potatoes, pumpkin, mangoes, apricots, spinach, kale, and fortified foods like cereals and margarine.

S12. Ans.(b)

Sol. Collagen is a protein that plays a crucial role in the structure and strength of connective tissues, including skin, tendons, and blood vessels. Vitamin C is required for the enzymatic reactions involved in collagen synthesis. It also acts as an antioxidant and aids in the absorption of iron, which is necessary for wound healing. Adequate vitamin C intake is important for maintaining healthy skin and promoting proper wound-healing processes.

Good dietary sources of vitamin C include citrus fruits, berries, kiwi, peppers, and leafy greens.

S13. Ans.(a)

Sol. Iron is necessary for the production of hemoglobin in red blood cells. Hemoglobin is a protein found in red blood cells that carries oxygen throughout the body. Iron is a key component of hemoglobin and is required for its proper synthesis and functioning. Without adequate iron, the body cannot produce sufficient hemoglobin, leading to a condition called iron-deficiency anemia. Good dietary sources of iron include red meat, poultry, fish, legumes, leafy greens, and fortified cereals.

S14. Ans.(d)

Sol. All of the vitamins listed in the options cannot be produced by our body and must be obtained from external sources such as food or supplements.

Our body cannot synthesize vitamin A, so we rely on dietary sources like animal products, orange and yellow fruits and vegetables, and dark leafy greens to obtain it.
Vitamin K is not produced in sufficient amounts by our body, and we need to obtain it from dietary sources such as green leafy vegetables, broccoli, and vegetable oils.
Similar to vitamins A and K, our body cannot produce vitamin C, and we must obtain it from food sources like citrus fruits, berries, peppers, and leafy greens.

S15. Ans.(d)

Sol. Potassium is a mineral that plays a vital role in proper nerve function and muscle contraction. It is an electrolyte that helps transmit electrical signals in the nervous system, enabling nerve impulses to travel efficiently and ensuring smooth muscle contraction.

Regarding muscle contraction, potassium ions are involved in depolarization and repolarization processes that occur during muscle contractions. It helps regulate the balance of other electrolytes like sodium and calcium, ensuring proper muscle function and preventing muscle cramps or weakness.

S16. Ans.(a)

Sol. The human body requires 13 essential vitamins for its proper functioning. These vitamins are necessary for various physiological processes and are classified into two categories: fat-soluble vitamins and water-soluble vitamins.

S17. Ans.(c)

Sol. Vitamin E and Vitamin K are classified as fat-soluble vitamins. Fat-soluble vitamins can dissolve in dietary fats and are stored in the body’s fatty tissues. They require dietary fat for absorption and can be stored in the body for longer periods.

Sources of Vitamin E: Nuts, seeds, vegetable oils (such as sunflower oil), green leafy vegetables, avocado, and fortified cereals.

Sources of Vitamin K: Green leafy vegetables (like kale and spinach), cruciferous vegetables, herbs (such as parsley and basil), fermented foods (like natto), and animal-based sources like liver and eggs.

S18. Ans.(d)

Sol. Vitamin K is necessary for blood clotting.

It plays a crucial role in the coagulation process, helping to form blood clots to prevent excessive bleeding. Vitamin K is involved in the activation of certain proteins involved in clotting, specifically the production of prothrombin and other clotting factors. Without sufficient Vitamin K, blood clotting may be impaired, leading to an increased risk of bleeding disorders. Good dietary sources of Vitamin K include green leafy vegetables, cruciferous vegetables, herbs, fermented foods, and animal-based sources like liver and eggs.

S19. Ans.(d)

Sol. Iodine is necessary for the proper functioning of the thyroid gland.

The thyroid gland uses iodine to produce thyroid hormones, which play a crucial role in regulating metabolism, growth, and development in the body.
Iodine deficiency can lead to thyroid-related disorders, such as goiter or hypothyroidism.
Good dietary sources of iodine include iodized salt, seafood, seaweed, and dairy products.

S20. Ans.(d)

Sol. Magnesium is a mineral that serves as a component of many enzymes in the body and is involved in various metabolic processes, including energy metabolism.

It plays a crucial role in converting food into energy by helping to break down carbohydrates, proteins, and fats.
Additionally, magnesium is involved in muscle and nerve function, DNA synthesis, and the maintenance of a healthy immune system. Good dietary sources of magnesium include green leafy vegetables, nuts, seeds, whole grains, and legumes.

**************************************************************************

இது போன்ற தேர்விற்கான தகவல் மற்றும் பாடக்குறிப்புகளை பெற ADDA247 தமிழ் செயலியை பதிவிறக்கம் செய்யுங்கள்