General Science - Biology

Biology is the most important chapter in General Science for SSC CGL, contributing 4 to 6 questions every year. The subject covers branches of biology, cell structure, genetics, human body systems, vitamins, diseases, and plant kingdom. Questions are direct, factual, and highly repeatable across years. Students who memorize the key facts given here will find this section easy to score in.

1. Major Branches of Biology

2. Cell - Theories, Structure and Functions

2.1 Animal Cell

• Ribosome is made up of ribosomal RNA and Protein
• Anton van Leeuwenhoek discovered single-celled living forms in 1674
• He used an advanced microscope and first saw free living cells in pond water algae Spirogyra
• Robert Hooke (English scientist) discovered the cell in 1665
• Leeuwenhoek's book is called 'Secretes of Nature'

Cell membrane:

• The cell membrane is selectively permeable for certain molecules on both sides
• Water can move through the membrane from lower to higher concentration (Statement II about water is false - water moves from high to low concentration actually; osmosis goes from lower solute to higher solute concentration)

Organelles:

• Ribosome: Synthesis of Protein in cells
• George Palade (1953) first saw the dense granular structure Ribosome under electron microscope
• Mitochondria: Power house of the cell - produces ATP through cellular respiration
• Golgi Apparatus: Processes and packages proteins
• Lysosome: Contains digestive enzymes, called suicide bags of cells

Cell membrane layers:

• In 1925, Gorter and F. Grendel examined the surface area of fat (lipid) and found that the fat surrounding cells should have two layers

2.2 Plant Cell

• The outermost covering of plant cells is called Cell Wall
• Pectin is present in the Middle Lamella between primary cell and secondary walls in plants - it accumulates in the early stages of cell expansion
• Cell Wall is found only in Plant cells (not in animal cells)
• Chlamydomonas - a type of unicellular eukaryotic cell whose diameter is ~10µm and about half its volume is occupied by a cup-shaped chloroplast

3. Tissues

3.1 Plant Tissues

• In plants, Xylem mainly transports water from roots to leaves and branches
• Phloem transports food materials (prepared by leaves through photosynthesis) to other parts of the plant
• In plants, both Xylem and Phloem are present as conducting tissues

Key difference:

• Xylem: Water and mineral transport (roots → all parts)
• Phloem: Food transport (leaves → all parts)

4. Biomolecules

4.1 Nucleic Acids (DNA and RNA)

• DNA (Deoxyribonucleic Acid) is a natural flame retardant
• James Watson and Francis Crick presented the double helix structure of DNA in 1953 - received Nobel Prize in 1962
• DNA is primarily stored in the Nucleus of cells (some also in Mitochondria and Chloroplasts)
• DNA controls all genetic activities through genes and regulates protein synthesis

4.2 Proteins and Fats

• Protein is known as 'Bodybuilding Food'
• Proteins are made up of Amino Acids which work as building blocks of cells
• Soybean has the highest protein per gram - contains 38-40% protein, 22% oil, 21% carbohydrate
• Casein is the main protein found in milk of mammals - a phosphoprotein that stays as Calcium and Caseinate
• Present in about 80% of cow's milk and 20-45% of human breast milk
• Casein protein contains about 15 amino acids

4.3 Enzymes

• Amylase is an enzyme that is present in all members of the animal kingdom (except Protozoa)
• It breaks down starch into glucose and maltose
• Found in human saliva - helps in digestion
• Lipase breaks down emulsified fat (secreted by pancreas)
• Pepsin digests protein (in stomach)
• Ptyalin enzyme is found in human saliva - converts starch (mand) into maltose

4.4 Carbohydrates

• Amylum is another name for Starch - found specially in seeds, fruits, bulbs, plant roots and stems of maize, potato, wheat and rice
• Starch is the most abundantly found carbohydrate in plant world
• Starch is the main food source for humans
• Starch contains two polysaccharides: Amylose and Amylopectin
• Monosaccharides are the simplest carbohydrates - Fructose and Glucose are examples
• Sucrose and Starch are NOT monosaccharides
• Amylase enzyme in human body helps break down carbohydrates
• Tyalin enzyme converts Starch (mand) into Maltose; Maltose into Glucose (in intestines)

5. Chromosomes

• Webbed neck is a characteristic of Turner Syndrome
• Turner Syndrome occurs in females who are born with only one X chromosome (Monosomy)
• Average: 1 in 5,000 females has Turner Syndrome
• Consequences: Female characteristics don't develop fully, short stature, reproductive organs underdeveloped, no menstruation - such females are eunuchs

6. Genetics

• American cell genetics scientist Joe Hin Tjio published a research in 1956 defining 2n = 46 as the accurate number of human chromosomes
• Wilson's Disease is a genetic disease in which Copper accumulates excessively in the body
• Symptoms: Fluid in legs or stomach, difficulties in speaking, swallowing or physical coordination, uncontrolled activities or muscle stiffness
• Redness (bleeding) is NOT a symptom of Wilson's Disease
• Transplantation between genetically identical individuals is called Isograft
• Autograft - transplantation within the same individual
• Allograft - transplantation between genetically different individuals of the same species

7. Organic Evolution

• The theory of extinction of dinosaurs due to a large meteorite impact on Earth is attributed to Luis Alvarez
• According to Professor Keller, besides meteorite impact, many environmental changes and volcanic eruptions also caused dinosaur extinction
• Appendix is a vestigial organ
• Vestigial organs are those that were fully developed in ancestors but gradually degraded over evolutionary time
• About 100 vestigial organs are found in humans - Appendix, body hair, ear muscles (Pinna), etc.
• "Survival of the Fittest" phrase belongs to Herbert Spencer
• Spencer used this phrase after reading Charles Darwin's 'On the Origin of Species' in his book 'Principles of Biology' (1864)

8. Animal Kingdom

8.1 Porifera (Sponges)

• Obelia is an organism showing Metagenesis (alternation of generations)
• It belongs to Phylum Nideria and is found mainly in shallow water on rocky shores
• Nideria phylum: No bilateral symmetry - radially symmetrical, soft-bodied animals - Jellyfish, Coral, Hydra
• Jellyfish belongs to Phylum Nideria (Cnidaria)
• Modern name of Phylum Coelentrata is Phylum Nideria
• Sponge (Porifera) main organisms: Euspongia, Spongilla, Sycon, Hyalonema, etc.

8.2 Platyhelminthes (Flatworms)

• Platyhelminthes (flat worms) have unsegmented, bilaterally symmetrical, soft bodies
• They have a triploblastic structure (three layers of cells)
• Devoid of any anus, skeleton and kidney
• Flame cell in Platyhelminthes works like a kidney and removes waste through pulsation
• Phylum Prithukrumi (Platyhelminthes) organisms are also called Flatworms
• Mismatched pair: Ankylostomal is related to Roundworm (not Pinworm)

8.3 Annelida

• Animals found in freshwater ponds, lakes and wetlands where setae or parapodia for locomotion belong to Phylum Annelida
• Also known as segmented worms
• A large phylum including Ringworms, Earthworms and Leeches with more than 22,000 species
• Gizzard (Pakwashay) is a structure in red earthworms that helps in grinding food

8.4 Arthropoda

• In Arthropoda phylum, body is divided into Head, Thorax and Abdomen
• It is the largest phylum in the animal kingdom
• Arthropoda shows bilateral symmetry
• Scorpion is an example of Arthropod
• Examples: Cockroach, Shrimp, Crab, Scorpion, Housefly, Centipede, Mite
• Honeybee has 5 eyes - 2 large compound eyes and 3 small occelli eyes
• Life cycle of butterfly: Egg → Larva → Pupa → Adult
• Grasshopper's ears are located on its Abdomen

8.5 Mollusca

• Snail (Ghongha) is a non-vertebrate animal (belongs to Mollusca)
• Birds, mammals and fish are all vertebrates (Chordata)
• Snail belongs to Phylum Mollusca - second largest phylum of invertebrates
• Their soft body is covered with a shell

8.6 Echinodermata

• Animals of this group named because of spiny skin and have a specialized water canal system for locomotion
• They have calcium-based internal skeleton
• Echinodermata (spiny-skinned animal) - water vascular system is a specialty
• Examples: Starfish, Sea Urchin, Sea Cucumber

8.7 Chordata

• In Chordates - they have a dorsal nerve cord (notochord)
• Heart is located at the ventral/lower part
• Tail is present behind the anus
• Frog is an egg-laying (oviparous) animal
• Egg-laying animals: Snake, Birds, Fish, Turtle
• Crocodiles have a four-chambered heart
• Humans belong to family Hominidae
• Scientific name of domestic dog: Canis lupus familiaris
• Marsupials carry young in a pouch - Example: Kangaroo

9. Human Body

9.1 Digestive System

• Lipase enzyme in digestion - breaks down emulsified fat
• Lipase is secreted by the pancreas
• It hydrolyzes triglycerides (fats) into fatty acids and glycerol
• An adult human has 4 Canine teeth
• Human tooth types:
  • Incisors: 8 (cutting)
  • Canines: 4 (tearing)
  • Pre-molars: 8 (chewing and grinding)
  • Molars: 12 (chewing and grinding)

9.2 Blood Circulatory System

• Iron is required for formation of Haemoglobin in blood
• It is found in Red Blood Cells (RBCs)
• Haemoglobin helps in transport of Oxygen and Carbon Dioxide
• White Blood Cells (WBCs) are called Soldiers of the Human Body
• WBCs protect us from infectious diseases and external diseases
• Also known as Leukocytes
• Adults have 6,000 to 8,000 WBCs per cubic millilitre
• Blood is produced in the Bone Marrow
• Red Bone Marrow produces RBCs; Yellow Bone Marrow produces WBCs
• Iron is also needed for Myoglobin formation (along with Haemoglobin)

9.3 Respiratory System

• Respiration of one molecule of Glucose produces 38 ATP molecules

9.4 Excretory System

• Creatinine is a chemical waste found normally in human urine
• Produced from metabolism of muscles in the human body
• About 2% of Creatine in human body converts to Creatinine daily
• Excreted from kidneys through urine
• Yellow colour of human urine is due to Urochrome (produced from decomposition of Haemoglobin)
• Normal urine is slightly acidic (pH = 6.00)
• Normal human produces 100-1800 ml of urine in 24 hours

9.5 Nervous System

• The amount of light entering the eye is controlled and regulated by the Pupil
• Pinna (karnpallav) is NOT a part of brain - it is the outer part of ear
• Pinna collects sound waves and sends them to the ear canal
• Brain parts: Thalamus, Pons, Medulla Oblongata, Cerebrum, Cerebellum
• Eustachian tube equalizes pressure on both sides of the eardrum
• Cerebellum (Anu Mastishk) plays an important role in motor control
• It also maintains balance and controls other physical activities
• Called Chota Mastishk (small brain)
• Mebomian gland is located in the eye
• It is a special type of sebaceous gland around the eyelids
• It secretes a fatty substance that prevents evaporation from eyes
• Upper eyelid has 50 and lower eyelid has 25 Mebomian glands

9.6 Skeletal System

• Adult human body has 206 bones
• Femur (Urvasthi) is the longest and strongest bone (thigh bone)
• Stapes, Malleus and Incus are ear bones - connected to each other through the eardrum

9.7 Endocrine System

• During breastfeeding, milk comes out due to hormone Prolactin
• Prolactin: Promotes breast growth during pregnancy and stimulates milk secretion after birth
• Oxytocin: Helps in labour pain at end of pregnancy and milk ejection afterward
• Estrogen: Responsible for development of secondary characteristics in females
• Progesterone: Its secretion from corpus luteum is responsible for signs related to pregnancy
• The gland that controls other endocrine glands is the Pituitary Gland
• Pituitary Gland is located in the Sella Turcica cavity in the brain
• Connected to hypothalamus by a stalk
• Size like a pea and weighs about 0.6 grams
• Also called Master Gland
• Insulin is secreted from the Pancreas
• Pancreas is a gland organ of digestion and endocrine system
• It produces Insulin, Glucagon, Somatostatin and other necessary hormones
• Thymus gland is located between the lungs
• It is pink, flat, bilobed gland that secretes Thymosin and Thymin hormones
• These help produce lymphocyte cells in the body that build antibodies creating immune system

9.8 Reproductive System

• Ovary is the primary reproductive organ of females

10. Vitamins and Nutrition

• Thiamine (Vitamin B₁) was the first B vitamin discovered in 1897 - deficiency causes Beri-Beri disease
• Vitamin K deficiency causes excessive bleeding from wounds - called anti-haemorrhagic vitamin
• Deficiency of Vitamin K causes Haemophilia

Nutrient-Example Matching:

• Vitamins and Minerals are helpful for metabolic reactions in our body
• RDA (Recommended Dietary Allowance) for cholesterol intake for healthy adults and children over 4 years: 300 mg/day

Vitamin Deficiency Diseases:

• Ascorbic Acid is the popular name for Vitamin C (C₆H₈O₆) - deficiency causes Scurvy

11. Human Diseases, Symptoms and Treatments

11.1 Diseases and Symptoms

• Malaria is NOT a genetic disease - caused by parasite Plasmodium spread by infected female Anopheles mosquito
• Acromegaly is a hormonal disorder (excess Growth Hormone from pituitary) - abnormal growth of hands, feet and face
• Correct disease-hormone pair: Diabetes - Insulin; Goitre - Thyroxine; Cushing Syndrome - Cortisol (NOT Adrenaline)

Disease-Organ Match:

• Glaucoma is NOT a form of cancer - it is an eye disease that damages the optic nerve
• According to WHO, glaucoma is the second largest cause of blindness in the world
• Cholera is caused by drinking contaminated water - caused by bacteria Vibrio cholerae (intestinal disease)
• Rickets: bone disease, mainly in children
• Anaemia: decrease in Haemoglobin in Red Blood Cells
• Tuberculosis (White Plague) is also known as Kshay Rog (Consumption/TB)
• Gout disease is caused mainly by malfunction of metabolism of Purin protein - excess Uric Acid accumulates in joints causing pain
• Epilepsy is a disorder where abnormal electrical discharge from brain cells causes seizures
• Cirrhosis is NOT communicable - it is a liver disease from excessive alcohol consumption
• Communicable diseases: AIDS, Hepatitis B, Syphilis
• Chicken Pox is caused by Varicella-Zoster virus - blisters and red spots appear on body
• Typhoid fever identified by Widal Test
• Typhoid caused by bacteria Salmonella Typhi through contaminated water and food
• Haemophobia is fear of Blood
  • Fear of darkness: Nyctophobia
  • Fear of heights: Acrophobia
  • Fear of water: Aquaphobia
• Measles (Khasra) is a communicable disease caused by Morbilli virus
• Goitre (Ghengha) is caused by deficiency of Iodine - Thyroid gland swells
• Weil's Disease affects Kidney - caused by Leptospira bacteria
• AIDS virus affects growth of T-cells in blood - HIV virus destroys T4 lymphocyte's ability to produce interleukins
• Leptospirosis is caused by bacteria (Leptospira Interrogans) - spreads from contaminated urine of infected animals

11.2 Treatment

• BCG vaccine (Bacillus Calmette-Guerin) is a vaccine for Tuberculosis (TB)
• Discovered by two French bacteriologists Albert Calmette and Camille Guérin - first used in 1921
• Penicillin antibiotic is obtained from Fungi (Penicillium notatum)
• Discovered by Alexander Fleming in 1928 - received Nobel Prize in 1945
• Other antibiotics from fungi: Neomycin, Terramycin
• DPT vaccine (Diphtheria, Pertussis, Tetanus) is a combined vaccine - protects against 3 infectious diseases
• Also known as Triple Antigen

12. Plant Kingdom

12.1 Fungi

• Fungal enzymes can break down waste into simple inorganic materials (catabolism)
• This process happens through catabolism - breaking large molecules into smaller units
• Rhizopus, Aspergillus, Mucor belong to Kingdom Fungi
• Euglena belongs to Phylum Protozoa (NOT Fungi)
• Yeast is a Fungus (saprophyte)
• Single-celled fungus with Chitin cell wall
• Used in wine/beer making and bakery industry
• Yeast ferments Shira (molasses) and flour making it soft

12.2 Algae

• F. E. Fritsch in 1935 explained the structure and reproduction system of algae
• Study of algae is called Phycology

Algae Classes:

• Lichen is a relationship between Algae and Fungi (symbiotic relationship)
• Algae component: Phycobiont; Fungi component: Mycobiont
• Lichens are good indicators of air pollution - they disappear in polluted areas

12.3 Bryophyta

• Plants in the Thallophyta group do not have clear body structure - generally called algae and are mainly aquatic

12.4 Gymnosperm

• Cycas is a plant of Gymnosperm class (NOT Pteridophyta)
• Gymnosperms have naked seeds (not enclosed in fruit wall)
• They are always naked both before and after fertilization

13. Plant Morphology

13.1 Stem

• Food in Onion is stored as Cellulose
• Cellulose was discovered by French scientist Anselme Payen in 1838
• Its chemical formula is (C₆H₁₀O₅)
• Garlic, lily and onion are examples of Bulb (Shalkakand)
• Potato is a Stem (Danthal/Tuber)
• Its botanical name is Solanum tuberosum
• Origin: Peru state of South America
• Other stem crops: Turmeric, Ginger, Onion

13.2 Flowers and Fruits

• Pedicel (Pushpa-vrunt) is NOT a part of a flower
• Parts of a flower: Calyx (Bahydal), Corolla (Dalapunj), Androecium (Punkesar/Pumang), Gynoecium (Streekesar/Jayaang)
• Development of fruit without fertilization is called Parthenocarpy
• Such fruits are seedless - Banana, Papaya, Orange, Grapes
• Gamete-ogamy: Process of producing male and female gametes through meiosis
• Apomixis: Formation of new plants through apomictic division and without fertilization - Sugarcane, Lemon
• Clove is obtained from the dried flower bud of the plant Eugenia caryophyllata (Myrtle family)

14. Plant Physiology

14.1 Photosynthesis

• Green light is the least effective in photosynthesis
• Photosynthesis happens most effectively in Red and Blue light and least effectively in Green light
• Reaction: 6CO₂ + 12H₂O → (with light and Chlorophyll) → C₆H₁₂O₆ + 6H₂O + 6O₂
• During photosynthesis, solar energy converts into chemical energy
• Green plants use energy from sunlight to synthesize Glucose from CO₂ and water

14.2 Respiration in Plants

• Fermentation is a type of Anaerobic Respiration - complex organic compounds breakdown with help of microorganisms - no Oxygen needed

14.3 Transport in Plants

• When water flows into Guard Cells, Stomata Opens

14.4 Nutrients

• Nitrogen Fixation is a process in which atmospheric Nitrogen is converted into Ammonia
• Biological Nitrogen Fixation discovered by German agricultural scientist Herman and Dutch scientist Martinus
• Symbiotic bacteria responsible for atmospheric nitrogen fixation found in Peas (Matar) - bacteria is Rhizobium
• Azolla increases soil fertility for Rice (Paddy) cultivation
• Azolla is a fern-like aquatic plant with blue-green algae Anabaena in its leaves
• This microbe works as fertilizer

14.5 Plant Diseases

• Blight is a type of plant disease caused by fungi or bacteria
• Crown Gall (Kireet Pitika) disease in plants is caused by bacteria Agrobacterium tumefaciens
• The bacteria inserts its DNA into plant cells causing excessive cell growth

14.6 Carnivorous Plants

• Drosera (Sundew) is a carnivorous plant
• Also known as Sundew plant
• It has red glandular hair with sticky fluid that traps insects
• Other carnivorous plants: Utricularia, Pitcher Plant, Dionaea (Venus Flytrap)
• Venus Flytrap is also a carnivorous plant

15. Reproduction in Plants

• Fertilization does not directly need light
• Ornithophily is pollination done by Birds
• Pollination by birds: Ornithophilous
• Pollination by wind: Anemophilous
• Pollination by insects: Entomophilous
• Pollination by water: Hydrophilous
• Pollination by snails: Malacophilous
• Fertilization in female flower occurs in the Ovary

16. Economical Importance of Flora and Fauna

• Silk worm feeds on Mulberry (Shahtut) leaves
• In life cycle of silk worm, commercial thread is produced in the Pupa stage
• Life cycle stages: Egg → Larva → Pupa → Adult insect (Imago)

17. Genetic Engineering and Biotechnology

• Credit for beginning Plant Tissue Culture work goes to Haberlandt
• Dolly, the first animal clone made at Roslin Institute in Scotland, was a Sheep

18. Major Biologists and Inventions

• Christian Barnard is famous for performing the world's first human heart transplant on December 3, 1967 in Cape Town, South Africa
• He transplanted the heart of 'Dennis Darvall' into 'Louis Washkansky's chest - Louis survived 18 days
• Edward Jenner discovered the first vaccine for Smallpox (Chechak)
• Alexander Fleming discovered Penicillin in 1928 - Nobel Prize 1945

19. Miscellaneous

Animal-Phylum Matching:

• Typhlops is a Blind Snake
• Numerical classification of plants is based on observable characteristics
• To control pest fish, predatory fish are used
• Cultivation of dwarf trees is called Bonsai
• Black Pepper plant is a creeper/vine (Bel)
• Alfalfa is a type of Grass - known as Rizka or Lucerne grass - used as animal fodder worldwide
• Bariatric surgery brings changes in the digestive system - reduces obesity
• Hibernation: Some animals like polar bears, turtles, frogs and snakes hide underground during winters in reduced metabolic state - sleep for 3-4 months continuously
• Body odour from sweat during humid heat is due to action of Bacteria on sweat
• Fungi (Fungi) does NOT appear in F-diagram (transmission of diseases through faeces)

20. Biology - Important One-Liners for SSC CGL

1. Viticulture = Grape cultivation
2. Apiculture = Honeybee rearing
3. Sericulture = Silkworm rearing
4. Entomology = Study of insects' relationship with humans and environment
5. Pedology = Science of Soil
6. Anton van Leeuwenhoek discovered single-celled organisms in 1674
7. Robert Hooke discovered the cell in 1665
8. Ribosome = made of ribosomal RNA + Protein; site of protein synthesis
9. Mitochondria = Power House of the cell
10. Cell Wall is found only in Plant cells
11. Pectin is in Middle Lamella between cell walls in plants
12. Xylem = Water transport; Phloem = Food transport in plants
13. DNA double helix discovered by Watson and Crick in 1953 (Nobel 1962)
14. DNA is mainly stored in the Nucleus
15. Protein = Bodybuilding Food
16. Soybean has highest protein per gram (38-40%)
17. Casein is the main protein in milk
18. Amylase enzyme present in all animals (except Protozoa)
19. Amylum = another name for Starch; found in maize, potato, wheat, rice
20. Fructose and Glucose are Monosaccharides; Sucrose and Starch are NOT
21. Webbed neck = symptom of Turner Syndrome
22. Human chromosomes: 2n = 46 (established by Joe Hin Tjio in 1956)
23. Wilson's Disease = genetic disease due to excess Copper accumulation
24. Isograft = transplantation between genetically identical (twin) individuals
25. Luis Alvarez = theory of dinosaur extinction by meteorite impact
26. Appendix = vestigial organ in humans
27. "Survival of the Fittest" = phrase by Herbert Spencer
28. Jellyfish = Phylum Nideria (Cnidaria)
29. Platyhelminthes = Flatworms; have triploblastic structure
30. Arthropoda = largest phylum; body divided into Head, Thorax, Abdomen
31. Honeybee has 5 eyes (2 compound + 3 occelli)
32. Butterfly life cycle: Egg → Larva → Pupa → Adult
33. Grasshopper's ears on its Abdomen
34. Snail = Mollusca (invertebrate)
35. Echinodermata = spiny-skinned animals; have water vascular system
36. Crocodile has 4-chambered heart
37. Humans belong to family Hominidae
38. Scientific name of domestic dog = Canis lupus familiaris
39. Marsupials carry young in pouch (e.g., Kangaroo)
40. Human tooth types: 8 Incisors, 4 Canines, 8 Pre-molars, 12 Molars
41. Iron needed for Haemoglobin formation
42. WBCs = Soldiers of Human Body = Leukocytes (6,000-8,000/mm³)
43. Blood produced in Bone Marrow (RBCs from Red Bone Marrow)
44. 1 molecule of Glucose → 38 ATP in respiration
45. Creatinine = chemical waste in urine
46. Yellow urine colour = Urochrome (from Haemoglobin decomposition)
47. Pupil controls amount of light entering the eye
48. Cerebellum = motor control and balance (called small brain)
49. Mebomian gland = in the eye (prevents tear evaporation)
50. Adult human = 206 bones
51. Femur (Thigh bone) = longest and strongest bone
52. Prolactin = hormone for milk secretion during breastfeeding
53. Pituitary Gland = Master Gland (controls other endocrine glands)
54. Insulin secreted from Pancreas
55. Thymus gland = between lungs; helps build immune system
56. Ovary = primary reproductive organ of females
57. Thiamine (B₁) = first B vitamin discovered in 1897; deficiency = Beri-Beri
58. Vitamin K deficiency = excessive bleeding; anti-haemorrhagic vitamin
59. Ascorbic Acid = Vitamin C; deficiency = Scurvy
60. Malaria = NOT genetic disease; caused by Plasmodium via Anopheles mosquito
61. Goitre (Ghengha) = deficiency of Iodine
62. Typhoid identified by Widal Test; caused by Salmonella Typhi
63. Chicken Pox = caused by Varicella-Zoster virus
64. Haemophobia = fear of Blood
65. Wilson's Disease = excess Copper in body
66. Epilepsy = abnormal electrical discharge from brain = seizures
67. Cirrhosis = liver disease; NOT communicable
68. BCG vaccine = for Tuberculosis; discovered by Calmette and Guérin (1921)
69. Penicillin obtained from fungi; discovered by Alexander Fleming in 1928
70. DPT vaccine = combined vaccine for Diphtheria, Pertussis, Tetanus
71. Yeast is a Fungus (saprophyte); used in wine and bakery industry
72. Lichen = symbiosis between Algae and Fungi; indicator of air pollution
73. Algae classes: Chlorophyceae (green), Phaeophyceae (brown), Rhodophyceae (red), Cyanophyceae (blue-green)
74. Potato is a Stem (tuber), NOT a root
75. Photosynthesis most effective in Red and Blue light; least in Green light
76. Fermentation = type of Anaerobic Respiration
77. Guard Cells fill with water → Stomata Opens
78. Nitrogen Fixation = atmospheric N₂ → Ammonia; bacteria Rhizobium in Pea roots
79. Azolla = increases fertility for rice/paddy cultivation
80. Blight = plant disease (fungal/bacterial)
81. Crown Gall = caused by Agrobacterium tumefaciens
82. Drosera = carnivorous plant (Sundew)
83. Venus Flytrap = carnivorous plant
84. Ornithophily = pollination by Birds
85. Silk worm feeds on Mulberry leaves; commercial thread in Pupa stage
86. Dolly = first cloned animal; a Sheep
87. Christian Barnard = first human heart transplant (1967)
88. Edward Jenner = first vaccine for Smallpox
89. Alexander Fleming = discovered Penicillin (1928)
90. Typhlops = Blind Snake
91. Bonsai = cultivation of dwarf trees
92. Alfalfa = type of Grass (used as animal fodder)
93. Bariatric surgery = changes in digestive system (treats obesity)
94. Hibernation = reduced metabolic state in winters (bears, turtles, frogs, snakes)
95. Body odour from sweat = due to Bacteria acting on sweat