Biology G8 Past Paper PDF

Biology 1. What is the powerhouse of the cell? Answer: Mitochondria 2. Female reproductive organ of a flower? Answer: Pistil 3. Male reproductive organ of a flower? Answer: Stamen 4. What is the term for the process by which green plants make their food using sunligh...

Biology 1. What is the powerhouse of the cell? Answer: Mitochondria 2. Female reproductive organ of a flower? Answer: Pistil 3. Male reproductive organ of a flower? Answer: Stamen 4. What is the term for the process by which green plants make their food using sunlight? Answer: Photosynthesis 5. What is the basic unit of heredity? Answer: Gene 6. What is the primary function of red blood cells? Answer: To carry oxygen 7. What is Mendel's Law of Segregation? Answer: During the formation of gametes, the alleles for a trait separate, so each gamete receives only one allele. Proponent: Gregor Mendel 8. What is Darwin's theory of natural selection? Answer: The process by which organisms better adapted to their environment tend to survive and produce more offspring. Proponent: Charles Darwin 9. What is the process of cell division called in somatic cells? Answer: Mitosis 10. What are the four nitrogenous bases in DNA? Answer: Adenine, Thymine, Cytosine, Guanine 11. What is the function of ribosomes? Answer: Protein synthesis 12. What is the term for organisms that can make their own food? Answer: Autotrophs 13. What is the process by which organisms maintain a stable internal environment? Answer: Homeostasis 14. What is the function of the chloroplast in plant cells? Answer: To conduct photosynthesis 15. What is the function of the enzyme DNA polymerase? Answer: It synthesizes DNA by adding nucleotides to the growing DNA strand. 16. What is the basic unit of life? Answer: The cell. 17. What is the powerhouse of the cell? Answer: Mitochondria. 18. What is the process by which plants make their own food? Answer: Photosynthesis. 19. What are the two stages of photosynthesis? Answer: Light-dependent reactions and the Calvin cycle. 20. What is the law of independent assortment? Answer: Genes for different traits segregate independently of each other during gamete formation. Proponent: Gregor Mendel 21. What is the double-helix structure of DNA? Answer: The shape of DNA, consisting of two intertwined strands. Proponent: James Watson and Francis Crick 22. What is the central dogma of molecular biology? Answer: DNA → RNA → Protein. 23. What is a mutation? Answer: A change in the DNA sequence. 24. What is the difference between mitosis and meiosis? Answer: Mitosis is cell division resulting in two identical daughter cells, while meiosis results in four genetically different gametes. 25. What is natural selection? Answer: The process where organisms better adapted to their environment tend to survive and reproduce. Proponent: Charles Darwin 26. What is an enzyme? Answer: A protein that speeds up chemical reactions in the body. 27. What are the four bases of DNA? Answer: Adenine, Thymine, Cytosine, and Guanine. 28. What is the function of ribosomes? Answer: To synthesize proteins. 29. What is homeostasis? Answer: The ability of an organism to maintain a stable internal environment. 30. What is osmosis? Answer: The diffusion of water through a selectively permeable membrane. 31. What is the function of the chloroplast? Answer: To conduct photosynthesis in plant cells. 32. What is the Krebs cycle? Answer: A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA. 33. What is the difference between aerobic and anaerobic respiration? Answer: Aerobic respiration requires oxygen, while anaerobic respiration does not. 34. What is a gene? Answer: A sequence of DNA that codes for a protein and thus determines a trait. 35. What is the Hardy-Weinberg principle? Answer: Allele frequencies in a population will remain constant in the absence of evolutionary influences. Proponent: Godfrey Hardy and Wilhelm Weinberg 36. What is the primary function of white blood cells? Answer: To defend the body against infections. 37. What is a zygote? Answer: A fertilized egg. 38. What is an allele? Answer: One of two or more versions of a gene. 39. What is the difference between genotype and phenotype? Answer: Genotype refers to the genetic makeup, while phenotype refers to the physical characteristics. 40. What are the three types of symbiotic relationships? Answer: Mutualism, commensalism, and parasitism. 41. What is genetic drift? Answer: A change in allele frequencies due to random events. 42. What are the components of the cell theory? Answer: All living organisms are made of cells, the cell is the basic unit of life, and cells arise from pre-existing cells. Proponents: Matthias Schleiden and Theodor Schwann 43. What is the function of the Golgi apparatus? Answer: To modify, sort, and package proteins for secretion. 44. What is the difference between prokaryotic and eukaryotic cells? Answer: Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have both. 45. What is apoptosis? Answer: Programmed cell death. 46. What is RNA transcription? Answer: The process of copying a segment of DNA into RNA. 47. What is the function of lysosomes? Answer: To break down waste materials and cellular debris. 48. What is an ecosystem? Answer: A community of interacting organisms and their physical environment. 49. What is a trophic level? Answer: A position in a food chain or ecological pyramid. 50. What is the function of red blood cells? Answer: To carry oxygen from the lungs to the body’s tissues. 51. What is a keystone species? Answer: A species on which other species in an ecosystem largely depend, such that its removal would drastically change the ecosystem. 52. What is adaptive radiation? Answer: The diversification of a group of organisms into forms filling different ecological niches. 53. What are the five kingdoms of life? Answer: Monera, Protista, Fungi, Plantae, and Animalia. 54. What is the difference between autotrophs and heterotrophs? Answer: Autotrophs produce their own food, while heterotrophs consume other organisms for food. 55. What is the function of the plasma membrane? Answer: To regulate the movement of substances in and out of the cell. 56. What are the four types of biomolecules? Answer: Carbohydrates, proteins, lipids, and nucleic acids. 57. What is the endoplasmic reticulum? Answer: An organelle involved in protein and lipid synthesis. 58. What is meiosis? Answer: The process of cell division that reduces the chromosome number by half, resulting in four gametes. 59. What is a codon? Answer: A three-nucleotide sequence on mRNA that codes for a single amino acid. 60. What is an antigen? Answer: A substance that triggers an immune response. 61. What is the difference between innate and adaptive immunity? Answer: Innate immunity is the first line of defense and is non-specific, while adaptive immunity is specific and involves memory cells. 62. What is the function of hemoglobin? Answer: To transport oxygen in the blood. 63. What is a species? Answer: A group of organisms that can interbreed and produce fertile offspring. 64. What is a biome? Answer: A large community of plants and animals that occupy a distinct region. 65. What is the nitrogen cycle? Answer: The process by which nitrogen is converted between its various chemical forms in the environment. 66. What does DNA stand for? Answer: Deoxyribonucleic acid 67. It is the blueprint of life; carries the genetic instructions for the development, functioning, growth, and reproduction of all living organisms? Answer: Deoxyribonucleic acid 68. What does DNA stand for? Answer: Deoxyribonucleic acid 69. Unit of heredity; specific segment of DNA that contains the instructions to make a particular protein or RNA molecule Answer: Gene 70. thread-like structures located inside the nucleus of animal and plant cells Answer: Chromosomes 71. How many chromosomes does a haploid cell have? Answer: 23 72. How many chromosomes does a diploid cell have? Answer: 46 73. How many pairs of chromosomes do humans normally have? Answer: 23 74. How many chromosomes in total do humans have? Answer: 46 75. In prokaryotes, the circular chromosome is contained in the ________ Answer: Cytoplasm 76. In eukaryotes, the chromosomes is contained in the ________ Answer: Nucleus 77. Genotypes: set of genes ; Phenotype: _______ Answer: observable traits 78. Genotypes: ______ ; Phenotype: observable traits Answer: set of genes 79. 2 types of alleles: Answer: Dominant & Recessive 80. Graphical representation for predicting all possible resulting genotype combinations of a specific cross or breeding experiment Answer: Punnett square 81. The conversion of glucose & oxygen to usable energy Answer: Respiration 82. The usable energy produced from cellular respiration is known as ____ Answer: Adenosine Triphosphate (ATP) 83. 2 stages of respiration: Answer: Breathing & Cellular respiration 84. Photosynthesis equation Answer:6CO2 + 6H2O → C6H12O6 + 6O2 A FEW PROMINENT FIGURES UNDER BIOLOGY: Who is the father of Evolution; proponent of the theory of evolution by Natural selection Answer: Charles Darwin Father of Genetics; proponent of the laws of inheritance Answer: Gregor Mendel Proponent of the Germ theory of disease and development of vaccines Answer: Louis Pasteur Coined the term "cell" after observing cork cells under a microscope. Answer: Robert Hooke