Comprehensive Biology Test
1. Normal Blood Pressure in Humans:
Ans: 120/80 mmHg
Explanation:
Normal human blood pressure is 120/80 mm of mercury. 120 represents systolic pressure (during heart contraction) and 80 represents diastolic pressure (during relaxation). It maintains blood flow balance.
2. Immune Response Trigger:
Ans: White Blood Cells (WBCs)
Explanation:
When a foreign substance enters the human blood, white blood cells recognize and destroy it. They produce antibodies and defend the body against infections and harmful microorganisms.
3. Vitamin Helping in Blood Clotting:
Ans: Vitamin K
Explanation:
Vitamin K is essential for synthesizing clotting factors in the liver. It prevents excessive bleeding by helping platelets form clots when an injury or bleeding occurs.
4. Control of Phototropic Movement:
Ans: Auxin
Explanation:
Auxins are plant hormones that control phototropism—the bending of a plant toward light. They promote cell elongation on the shaded side, causing the plant to grow toward light.
5. Animal Not Affected by High Salt Intake:
Answer: Camel
Explanation:
Camels can tolerate high salt intake without developing high blood pressure. Their kidneys efficiently conserve water and excrete excess salt, maintaining osmotic balance in desert conditions.
6. Blood Pressure Regulation:
Ans: Adrenal Gland
Explanation:
The adrenal gland secretes adrenaline and aldosterone, which regulate heart rate, water balance, and blood vessel constriction, helping control and stabilize blood pressure levels in the body.
7. Bird Wings and Insect Wings Are:
Ans: Analogous Organs
Explanation:
Both bird and insect wings perform the same function—flying—but differ in origin and structure. Such organs with similar functions but different ancestry are called analogous organs.
8. Number of Neck Canal Cells in Fern Archegonium:
Ans: One
Explanation:
In ferns, the archegonium (female sex organ) contains one neck canal cell that helps guide the male gamete (sperm) to the egg during fertilization for zygote formation.
9. Gene Collection in a Population:
Ans: Gene Pool
Explanation:
A gene pool includes all the genetic information (alleles) present in a population. It represents the total variation available for evolution and adaptation through genetic recombination.
10. Coding Segments of DNA:
Ans: Exons
Explanation:
Exons are DNA sequences that code for proteins. During RNA processing, exons remain in the mature mRNA, while non-coding introns are removed before translation.
11. Chromosome Number in Human Somatic Cells:
Ans: 46
Explanation:
Humans have 46 chromosomes (23 pairs) in each body cell. One set comes from each parent, containing genes that control traits and ensure proper growth and development.
12. Enzyme for Protein Digestion:
Ans: Pepsin
Explanation:
Pepsin, secreted in the stomach, breaks proteins into smaller peptides. It works optimally in acidic conditions (pH 1.5–2) provided by hydrochloric acid in gastric juice.
13. Technique to Detect Radioactive Elements in Living Cells:
Ans: Autoradiography
Explanation:
Autoradiography tracks radioactive isotopes in cells. It uses photographic film to visualize cellular components where radioactive substances accumulate, helping study metabolism and molecular activity.
14. Edible Part of Ginger and Potato:
Ans: Stem
Explanation:
Although they grow underground, both ginger and potato are modified stems. Potato is a tuber storing food; ginger is a rhizome used for storage and vegetative propagation.
15. Process by Which Plants Make Food:
Ans: Photosynthesis
Explanation:
Photosynthesis occurs in green plants using sunlight, carbon dioxide, and water to produce glucose and oxygen. It takes place mainly in chloroplasts containing chlorophyll pigments.
16. Hard Enamel Layer of Teeth Is:
Ans: Calcium Phosphate
Explanation:
Tooth enamel is mainly made of calcium phosphate in the form of hydroxyapatite crystals. It is the hardest substance in the human body and protects teeth from decay.
17. Snake Declared Endangered for Its Skin:
Ans: Russell’s Viper
Explanation:
The Russell’s viper, hunted for its attractive skin, is now a protected species. It is a venomous snake important for antivenom production and ecological balance.
18. Largest Bone in Human Body:
Ans: Femur
Explanation:
The femur, or thigh bone, is the longest and strongest bone in the human body. It supports body weight and connects the hip to the knee joint.
19. Study of Cancer:
Ans: Oncology
Explanation:
Oncology is the medical study of cancer, including its causes, development, diagnosis, and treatment. Oncologists specialize in managing tumors and related therapies like chemotherapy.
20. Filtration Unit of Kidney:
Ans: Nephron
Explanation:
Each kidney contains about a million nephrons. They filter blood, remove wastes like urea, and regulate water and salt balance to form urine and maintain homeostasis.
21. Protein Found in Egg:
Ans: Egg White (Albumen)
Explanation:
The white part of an egg, called albumen, contains proteins like ovalbumin. These proteins are essential for body tissue repair, growth, and various metabolic functions.
22. A Boy Inherits Chromosomes from His Father:
Answer: 22 + Y
Explanation:
Males have XY chromosomes. A boy inherits 22 autosomes and one Y chromosome from his father, determining his male sex. The X chromosome comes from the mother.
23. Carnivorous Plants Grow in Soil Deficient in:
Ans: Nitrogen
Explanation:
Carnivorous plants like pitcher plants and Venus flytraps grow in nitrogen-poor soils. They trap insects to supplement nitrogen for making proteins and enzymes necessary for growth.
24. Center of Cellular Respiration:
Ans: Mitochondria
Explanation:
Mitochondria are known as the “powerhouse of the cell.” They produce energy (ATP) through cellular respiration by breaking down glucose and oxygen to power cellular activities.
25. Thalassemia Affects Which Part of the Body ?
Ans: Blood
Explanation:
Thalassemia is a genetic blood disorder where hemoglobin production is abnormal, causing anemia, fatigue, and growth problems. It mainly affects red blood cells’ oxygen-carrying ability.
26. Elements Essential for Bone and Teeth Formation:
Answer: Calcium and Phosphorus
Explanation:
Calcium and phosphorus form hydroxyapatite crystals, the main structural component of bones and teeth, giving them strength and rigidity necessary for body support and dental health.
27. Cancer Caused by Radioactive Strontium-90:
Answer: Skin Cancer
Explanation:
Strontium-90 emits beta radiation, which damages skin cells and DNA, increasing the risk of mutations that lead to skin cancer when exposure is prolonged or unsafe.
28. International Movement for Environmental Protection:
Answer: Greenpeace
Explanation:
Greenpeace is a global organization focused on environmental conservation. It campaigns against pollution, deforestation, and climate change to protect Earth’s natural ecosystems and biodiversity.
29. Weeds Useful in Controlling Pollution:
Ans: Parthenium and Elephant Grass
Explanation:
Parthenium and elephant grass can absorb harmful pollutants and heavy metals from soil and air, helping in bioremediation and improving environmental quality naturally.
30. Alzheimer’s Disease Affects:
Ans: Brain (Neurological Disorder)
Explanation:
Alzheimer’s is a brain disorder that causes memory loss and cognitive decline. It results from degeneration of neurons and abnormal protein deposits in the brain.
31. Life-Containing Sources in the Biosphere Are:
Ans: Biological Sources
Explanation:
Biological sources include living organisms like plants, animals, and microorganisms that maintain life processes, recycle nutrients, and contribute to the functioning of the biosphere.
32. Disease Caused by Excessive Alcohol Consumption:
Ans: Cirrhosis
Explanation:
Cirrhosis is a liver disease caused by long-term alcohol abuse. It leads to scarring of liver tissue, reducing its ability to detoxify blood and produce bile.
33. Solitary (Single) Racemose Inflorescence Found in:
Ans: Papaver (Poppy)
Explanation:
In the poppy plant, a single flower arises at the tip of the peduncle—known as a solitary racemose inflorescence—showing determinate growth and terminal flowering.
34. Bacteria Found in Root Nodules of Legumes:
Ans: Rhizobium
Explanation:
Rhizobium bacteria live symbiotically in the roots of leguminous plants. They fix atmospheric nitrogen into usable forms, enriching soil fertility and promoting plant growth.
35. If Xylem and Phloem Are on the Same Radius:
Ans: Collateral Vascular Bundle
Explanation:
A collateral vascular bundle has xylem and phloem arranged side by side on the same radius, common in dicot and monocot plant stems.
36. Total Number of Inner Transition Elements:
Ans: 29
Explanation:
There are 29 inner transition elements, including lanthanides and actinides. They fill the f-orbital and exhibit complex chemical properties and variable oxidation states.
37. Number of Amino Acids Found in the Human Body:
Ans: 20
Explanation:
The human body uses 20 standard amino acids to build proteins. Nine are essential (from diet), while the rest are synthesized within the body.
38. Major Nutrient Required in Large Quantity by Plants:
Ans: Nitrogen
Explanation:
Nitrogen is a macronutrient essential for chlorophyll, protein, and nucleic acid formation. Plants absorb it as nitrates and ammonium ions for healthy growth.
39. Lichen Is an Example of:
Ans: Symbiosis
Explanation:
Lichen is a symbiotic association between an alga and a fungus. The alga makes food through photosynthesis, while the fungus provides structure and water absorption.
40. Water Transport in Plants:
Ans: Apoplast and Symplast
Explanation:
Water moves through plants via two pathways: apoplast (through cell walls and intercellular spaces) and symplast (through cytoplasm connected by plasmodesmata), ensuring efficient nutrient and water distribution.
41. Parasite Causing Malaria:
Ans: Plasmodium
Explanation:
Plasmodium species, transmitted by female Anopheles mosquitoes, invade red blood cells and liver, causing malaria symptoms like fever, chills, anemia, and fatigue in humans.
42. How Indian Industry Benefits from Agriculture:
Ans: By supplying raw materials and labor
Explanation:
Agriculture provides raw materials like cotton and jute for industries and employs workers who earn wages, boosting industrial development, food security, and economic growth.
43. Food Crop with Highest Protein:
Ans: Soybean
Explanation:
Soybean is rich in protein (around 36–40%), essential for human and animal diets. It is widely used in food products, oil extraction, and as livestock feed.
44. Estimated Number of Skeletal Muscles in Human Body:
Ans: 700
Explanation:
The human body has about 700 skeletal muscles responsible for voluntary movements, posture maintenance, and coordination. Each muscle contains muscle fibers working together for strength.
45. Study of Ecology:
Ans: Relationship of Organisms with Environment
Explanation:
Ecology studies interactions between plants, animals, and their environment. It examines ecosystems, biodiversity, energy flow, and adaptation to understand natural balance and environmental conservation.
46. Composition of Human Connective Tissues:
Ans: White Fibers and Some Yellow Elastic Fibers
Explanation:
Connective tissues are made of white collagen fibers providing strength and yellow elastic fibers providing flexibility, supporting organs, bones, and tissues structurally in the human body.
47. Respiration in Fishes:
Ans: By Gills
Explanation:
Fishes respire using gills, which extract dissolved oxygen from water. Gills have filaments and lamellae to increase surface area for efficient gas exchange.
47. Largest Bird in the World:
Ans: Ostrich
Explanation:
Ostrich is the largest living bird, flightless, native to Africa. It has strong legs for running and produces large eggs, adapted to savanna and desert ecosystems.
49. Clitellum Found in:
Ans: Earthworm
Explanation:
The clitellum is a thick, glandular segment of earthworms that secretes mucus for cocoon formation during reproduction, facilitating external fertilization of eggs.
50. Maximum Permissible Hardness in Drinking Water:
Ans: 300 mg/L (as CaCO₃)
Explanation:
Total hardness in drinking water is due to calcium and magnesium salts. The safe limit is 300 mg/L to prevent health issues and maintain palatability.