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Table of Content Page No. Biology 1-72 1. Cell, Genetics & Evolution……………………....………………………………………………………………...

Table of Content Page No. Biology 1-72 1. Cell, Genetics & Evolution……………………....……………………………………………………………… 1-6 2. Tissue……………………………………………………………………………………………………………… 7-11 3. Biomolecules……………………………………………………………………………………………………... 12-14 4. Zoology………………………………………………………………………………………………………..….. 15-22 (Zoology, Animal Kingdom) 5. Botany…………………………………………………………………………………………………………….. 23-33 (Botany, Plant Kingdom) 6. Human Body……………………………………………………………………………………………………... 34-53 (Nervous System, Sensory Organs, Skeletal System, Digestive System, Respiratory System, Circulatory System, Excretory System, Endocrine System, Reproductive System) 7. Discoveries and Scientific Development……………………....………………………………………... 54-57 8. Human Diseases……………………....……………………………………………………………..………… 58-66 9. Scientific Names……………………....…………………………………………………………………...…... 67-68 10. Biology in Everyday Life……………………....…………………………………………………………..… 69-72 Chemistry 73-162 11. Basic Concepts of Chemistry……………………....………………………………………………………. 73-76 12. Atoms and Molecules……………………....……………………………………………………………........ 77-81 13. Properties of Elements & Compounds……………………....…………………………………………... 82-95 14. Periodic Table……………………....……………………………………………………………….…………. 96-108 15. Chemical Bond……………………....……………………………………………………………..…………... 109-112 16. Carbon & its Compounds……………………....…………………………………………………..………... 113-117 17. Acid, Base & Salts……………………....……………………………………………………………………... 118-125 18. Solutions……………………....……………………………………………………………………….………... 126-131 19. Gases & its Laws……………………....………………………………………………………………….…..... 132-136 20. Chemical Reaction……………………....…………………………………………………………………..... 137-143 21. Metals & Non-Metals……………………....…………………………………………………………..……... 144-150 22. Chemistry in Everyday Life……………………....…………………………………………………….…… 151-162 Physics 163-292 23. Units, Dimensions & Formula……………………....……………………………………………………..… 163-169 24. Motion……………………....………………………………………………………………………………..…... 170-178 25. Forces……………………....…………………………………………………………………………...………... 179-188 26. Work, Energy & Power……………………....……………………………………………………………….. 189-204 27. Gravity……………………....…………………………………………………………………………………..... 205-212 28. Wave & Optics……………………....………………………………………………………………..………... 213-249 (Wave, Optics) 29. Heat and Temperature……………………....……………………………………………………..………... 250-256 30. Electricity & Magnetism……………………....……………………………………………………….……... 257-288 (Current Electricity, Magnetism) 31. Laws & Principles……………………....………………………………………………………………….…... 289-290 32. Measuring Instruments……………………....…………………………………………………………..…... 291-292 CHAPTER WISE WEIGHTAGE ANALYSIS CHAPTER꞉ 1 CELL, GENETICS & EVOLUTION 1. The smallest unit of the life capable of independent A) Nuclear membrane B) Ribosome existence is꞉ [RRB NTPC 2021] C) Cell wall D) Cytoplasm A) Protoplasm B) Cytoplasm 14. Name the process that causes living cells to expand in size C) Cell D) Vacuoles and shape when placed in a hypotonic solution. 2. CSIR scientists have conducted a genetic study for the first [RRB Group D 2022] time in India. Where has the study been conducted? A) Diffusion B) Osmosis [RRB NTPC 2021] C) Transpiration D) Photosynthesis A) Hyderabad B) Lakshwadeep 15. How many pairs of sex chromosomes are present in C) Kochi D) Andaman humans? [RRB Group D 2022] 3. In the respiration process, complex organic compounds A) 2 pairs B) 1 pair such as glucose are broken down to provide energy in the C) 3 pairs D) 4 pairs form of ________ [RRB NTPC 2021] 16. Name the process through which gaseous exchange takes A) PTA B) NAC place across the cell membrane. C) CAL D) ATP A) Diffusion B) Osmosis 4. The branch of science that studies cells is called ________. C) Endocytosis D) Absorption A) Cytology B) Entomology 17. Which molecule is known as the 'Energy Currency' of the C) Homoplastic D) Hormonology cell [RRB Group D 2022] 5. The other term for genetic engineering is꞉ [RRB NTPC 2016] A) Pyruvic acid B) Glucose A) DNA fingerprinting B) DNA editing C) ADP D) ATP C) Recombinant DNA D) Gene therapy 18. A basic event in protein synthesis is the creation of a/an technology ____. [RRB Group D 2018] 6. ________ are a kind of waste disposal system of the cell. A) DNA copy B) RNA copy They help to keep the cell clean by digesting any foreign C) mRNA copy D) DNA and RNA copy materials as well as worn-out cell organelles. [RRB NTPC 2021] 19. ______ mutation is NOT hereditary. [RRB Group D 2018] A) Mitochondria B) Plastids A) Deletion B) Insertion C) Lysosomes D) Golgi C) Somatic D) Duplication 7. Alignment of chromosomes in the center of the cell at the 20. Cells of ______ and ______ tissues are living cells. equatorial plate constitutes which stage of mitosis? [RRB NTPC 2021] [RRB Group D 2018] A) Telophase B) Anaphase A) Parenchyma and B) Sclerenchyma and sclerenchyma tracheids C) Prophase D) Metaphase C) Collenchyma and D) Parenchyma and 8. Which of the following organelle of the eukaryotic cells are sclerenchyma collenchyma also called suicidal bags? [RRB NTPC 2022] 21. __________ character predominates and is clearly seen in A) Golgi body B) Mitochondria FI Generation. [RRB Group D 2018] C) Lysosomes D) Chloroplast A) Inherited B) Allele 9. How many pairs of autosomes does a normal human have? C) Dominated D) Recessive [RRB NTPC 2022] A) 22 B) 44 22. ______ promote(s) cell division. [RRB Group D 2018] A) Abscisic acid B) Cytokinins C) 23 D) 1 C) Gibberellins D) Auxin 10. Which of the following is called the 'powerhouse of the cell'? 23. _______Theory of Evolution tells us how life evolved from A) Red blood cells B) Mitochondria simple to more complex forms. [RRB Group D 2018] A) Darwin's B) Wallace C) White blood cells D) Plasma membrane C) Mendel's D) Lamarck's 11. The transformation of silkworms and frog larvae into adults through drastic changes is called __________. 24. Sclerenchyma is composed of ______. [RRB Group D 2018] [RRB NTPC 2022] A) WBC B) complex cell A) mutation B) metamorphosis C) non-living cell D) RBC C) diversification D) transfiguration 25. ________ is the sequence of gradual changes that take 12. In Mendel's experiment, when F1 generation plants were place in the primitive organisms over millions of years, self-pollinated, what was the genotypic ratio? resulting in the formation of new species. [RRB Group D 2018] [RRB Group D 2022] A) Evolution B) Fossils A) 1 ꞉ 2 ꞉ 3 B) 1 ꞉ 2 ꞉ 1 C) Analogous organs D) Homologous organs C) 2 ꞉ 2 ꞉ 1 D) 3 ꞉ 2 ꞉ 1 26. The organs that have different basic structure (or different 13. Which of the following cellular components is absent in basic design) but have similar appearance and perform most of the prokaryotes? [RRB Group D 2022] similar functions are called꞉ [RRB Group D 2018] 1 A) fossils B) homologous organs 40. In a cell that is NOT dividing, DNA is present as part of the C) analogous organs D) biogenetic law ______. [RRB Group D 2022] A) chromosome B) nucleoplasm 27. Human genetics can be traced back to꞉ [RRB Group D 2018] C) gene D) chromatin material A) African origin B) American origin C) South Asian origin D) East Asian origin 41. Which one of these is found in human Females only? A) XX chromosome B) X-chromosome 28. The fungal cell wall is made up of hard complex sugars C) XYY chromosome D) Y-chromosome called _______. [RRB Group D 2018] A) Chitin B) Lignin 42. What is the full form of RNA? C) Pectin D) Cellulose A) Ribo nucleic acid B) Ribo nuclear acid 29. In a Mendelian test, tall pea plants with violet flowers and C) Retinal nucleic acid D) Robert nuclear acid short flowers with white flowers were used for breeding. All the 43. Differentiation in organisms leads to _____. flowers of their progeny were violet in color but about half of [RRB Group D 2018] the plants were small in stature. This shows that the genetic A) Origin and Development of B) Choose the most desirable composition of tall plants can be represented as__________. Diversity properties [RRB Group D 2018] C) Survival of organism D) Complex form of origin A) TtWW B) TTww 44. Which of the following molecules govern the inheritance C) TtWw D) TTWW of a trait by the offspring? [RRB Group D 2022] 30. On what basis did Mendel give the law of purity of A) Only maternal DNA B) Paternal and maternal DNA gametes? [RRB Group D 2018] C) Proteins D) Only paternal DNA A) Bank Cross B) Dihybrid Cross 45. Every germ cell will take one chromosome from each pair C) Test Cross D) Monohybrid Cross and these may be of either maternal or paternal origin. When 31. The phenotypic ratio in the F2 generation is ________. two germ cells combine, they will restore the normal number [RRB Group D 2018] of chromosomes in the progeny, ensuring the stability of the A) 1 ꞉ 2 ꞉ 3 B) 9 ꞉ 3 ꞉ 3 ꞉ 1 DNA of the species. C) 1 ꞉ 3 ꞉ 3 ꞉ 9 D) 1 ꞉ 2 ꞉ 5 Such a mechanism of inheritance is explained in 32. Which of the following is a unicellular green algae? _______________. [RRB Group D 2018] [RRB Group D 2022] A) Chara B) Ulothrix A) mutation in species B) variation in chromosomal C) Spirogyra D) Chlamydomonas number C) speciation of organisms D) the results of the Mendel's 33. Mendel's laws apply only when꞉ [RRB Group D 2018] experiments A) Parents are pure breeding B) Parent is codominant 46. The breakdown of glucose to pyruvate takes place in the C) Characters are recessive D) Characters are linked ________ during energy production. [RRB ALP 2018] 34. In which kingdom would you place all organisms, which A) mitochondria B) cytoplasm are multicellular eucentric with a cell wall? [RRB Group D 2018] C) nucleus D) endoplasmic reticulum A) protista B) plantea 47. Chlorophyll pigment is present in which of the following C) monera D) animalia components of a cell? [RRB Group D 2022] 35. Gene mutation is caused by which of the following? A) Ribosomes B) Mitochondria [RRB Group D 2018] C) Lysosomes D) Chloroplasts A) Reproduction B) Change in protein sequence 48. Which of the following statement(s) is/are incorrect? C) Change in the sequence of D) Secretion of enzymes of A. The full name of DNA is deoxyribo-nucleic acid. nitrogenous bases hormones B. It is the chemical element present in the chromosome which carries the genetic property. 36. The basic source of biological diversity is ________- C. DNA is a polynucleotide, nucleo-tide is the basic structural [RRB Group D 2018] A) mutation B) cosmic evolution unit of DNA, which is made up of two components. [RRB Group D 2018] C) inheritance D) fermentative action A) C and B B) A and C 37. _________ is a part of DNA, which provides information for C) Only C D) Only A a protein. [RRB Group D 2018] A) Chromosome B) Nucleus 49. A girl child has which of the following combinations of chromosomes in her cells? [RRB ALP 2018] C) Trait D) Gene A) 44 autosomes + XX B) 22 autosomes + XX 38. Alleles are꞉ [RRB Group D 2018] C) 44 autosomes + XY D) 22 autosomes + XY A) Alternative forms of B) Gene variant enzymes 50. Which of the following statements is NOT true of Meiosis? C) Alternate form of D) Form of imperfect [RRB ALP 2018] chromosome predominance A) As a consequence of B) Meiosis takes place in Meiosis, the number of gonads for production of 39. The sex of the children is determined by the hereditary chromosomes is doubled in gametes. chromosome inherited from [RRB Group D 2018] the resulting cells. A) Father B) Nature C) Meiosis takes place in two D) During Meiosis, the genes C) Mother and Father D) Mother phases. of the parent cells are mixed in the resulting cells. 2 51. What is the main difference observed between a slide of A) Because they contain B) Because they are the human cheek cells and a slide of onion peel when viewed ribosomes and DNA power-house of the cell under a compound microscope? [RRB Group D 2022] C) Because they are the store D) Because they can digest A) Presence of cell wall in B) Presence of plastids in of cellular contents microorganisms human cheek cells cheek cells 56. How many autosomes will be present in a sexually C) Presence of mitochondria D) Presence of cell wall in reproducing organism with the chromosome number 2n = 18? in onion peel cells onion peel cells [RRB Group D 2022] 52. Which of the following statements is true? [RRB ALP 2018] A) 18 B) 16 A) The term 'Genetics’ was B) In human beings, there are C) 15 D) 17 coined by J. D. Watson in 46 chromosomes. Of these, 42 1906. (21 pairs) are autosomes and 4 57. The process of division of a cell into two identical daughter (2 pairs) are sex chromosomes. cells is called? [RRB Group D 2018] C) Mendel was the first D) A DNA molecule is made A) Multiple fragmentation B) Bifurcation scientist to visualise a gene as up of two long polynucleotide C) Revival D) Spore formation an inheritance in 1886. strands forming a double 58. In which of the following processes, the cell is involved in helical structure (double helix) the generation of an exact copy of another living part or a just like a spiral staircase. complete organism? [RRB Group D 2018] 53. Which of the following statements is FALSE? A) Cloning B) In vitro fertilization (IVF) [RRB Group D 2022] C) Fructification D) Regeneration A) Each gene controls one B) The two alleles are brought character. together at the time of 59. Ancient hominids who are placed in the category of homo gamete formation sapiens were - C) Every germ cell will take D) Genes are located on A. Ergaster line one chromosome from each chromosomes. B. Cro - Magnon pair. C. Neanderthal 54. Some features of a prokaryotic cell are mentioned below. D. Proconsuls Select the INCORRECT option. [RRB Group D 2022] [RRB NTPC 2016] A) Very small in size B) Membrane-bound cell A) D B) B organelles present C) C D) A C) Single chromosome D) Nuclear region known as 60. ______ affects the atoms in living cells and thereby nucleoid damages their genetic material (DNA). [RRB ALP 2019] 55. Why are mitochondria considered as a 'weird' organelle? A) Chlorinated water B) Chloroform [RRB Group D 2022] C) Benzene vapours D) Ionising radiation ANSWER KEY Q. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Ans C B D A C C D C A B B B A B Q. 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Ans B A D C C D C B A C A C A A Q. 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Ans A D B D A B C A D B A D A A Q. 43 44 45 46 47 48 49 50 51 52 53 54 55 56 Ans D B D B D C A A D D B B A B Q. 57 58 59 60 Ans B A B D 3. ATP stands for Adenosine Triphosphate. ATP is the energy- SOLUTIONS carrying molecule used in cells. In the respiration process, 1. A cell is the smallest unit capable of independent existence complex organic compounds such as glucose are broken which can reproduce itself. All living organisms, except for down to provide energy in the form of ATP. Mitochondria viruses, are composed of one or more cells. Single-cell produces ATP molecules, which is why it is known as the cell organisms; such as, bacteria, protozoa, and other micro- powerhouse. In mitochondria, energy is stored in the form of organisms are termed unicellular, while plants and animals ATP. ATP acts as the energy currency of the cell. that contain many cells are termed multicellular. 4. Branch of science that studies cells is called Cytology. All 2. CSIR scientists have conducted a genetic study for the first living organisms are made up of cells. The cell was discovered in 1665. The first cells from an organism were observed by time in Lakshwadeep, India. A team of researchers led by K Robert Hooke. Thangaraj at the Council of Scientific and Industrial Research (CSIR)-Centre for Cellular and Molecular Biology, Hyderabad 5. Genetic engineering, a practice used to modify an have performed a genetic study on the Lakshadweep organism's DNA, is synonymously known as Recombinant DNA islanders. The genetic study on the Lakshadweep islanders technology. This process involves manipulating an organism's took place for the first time and the results were published in genes by introducing, removing, or altering genetic material. It scientific reports on 6 May 2019. differs from DNA fingerprinting, which identifies genetic sequences; DNA editing, focusing on specific gene 3 modifications; and gene therapy, aimed at treating diseases of low concentration to one of high concentration. It is by altering genes. Recombinant DNA technology a passive process that takes place without using any energy. encompasses a broader range of genetic manipulation In a hypotonic solution, a cell will gradually inflate and grow techniques. until it bursts. It can occur in any solvent, including gases and 6. Lysosomes are a kind of waste disposal system of the cell. supercritical liquids. They help to keep the cell clean by digesting any foreign 15. A total of 46 chromosomes make up a human, including materials as well as worn-out cell organelles. one pair of XX or XY chromosomes and 22 pairs of numbered 7. Mitosis is a kind of cell division in which one cell (the chromosomes called autosomes. Sex chromosomes, the 23rd mother) divides to generate two genetically identical new cells pair, are different in males and females. In contrast to males, (the daughters). Mitosis is the stage of the cell cycle's division who have one X and one Y chromosome, females have two process in which the DNA of the cell's nucleus is split into two copies of the X chromosome. By size, the 22 autosomes are equal sets of chromosomes. In Metaphase the chromosomes numbered. are perfectly lined up end-to-end along the cell's equator. The 16. An essential mechanism by which gases are exchanged in mitotic spindle threads extend from the centrioles, which are a cell is diffusion. The difference in concentration pressure is now at opposing poles of the cell. what primarily controls this process. As a result, the gases shift 8. Lysosomes are membrane-bound vesicular structures from a place of high concentration to one of low formed by the process of packaging in the Golgi concentration. The main time that diffusion occurs in plant apparatus. These are also called ''Suicidal bags'' because of cells is during photosynthesis when carbon dioxide diffuses their phagocytic activity. Lysosome keeps the cell clean by into plant cells through the stomata on the leaf. digesting any foreign material as well as worn-out cell 17. Cells use and store energy in the form of ATP. It is organelles. commonly referred to as the energy currency since it readily 9. There are 46 chromosomes in all, divided into 23 pairs in releases energy in the bond that joins the second and third humans.These 22 which are the same for both males and phosphate groups. Three serially connected phosphate females are referred to as the autosomes.There are differences groups, a ribose sugar, and a nitrogenous base (adenine) between the sexes in the 23rd pair of chromosomes, or make up the nucleoside triphosphate (ATP) structure. allosomes, which is the sex chromosome.When compared to 18. The mRNA provides the template for the Genetic Code. A females, who have two copies of the chromosome (44A + XX), gene is used to build a protein using the following two step males only have one and one chromosome (44A+ XY). process i.e. Transcription and Translation. Transcription꞉ It is 10. The proteins synthesized by the proteins in mitochondria the process by which DNA is copied to mRNA, which carries are utilized to generate adenosine triphosphate (ATP) from the the information needed for protein synthesis. Translation꞉ It is food. This ATP acts as the energy currency of the cell, because the process that takes the information passed from DNA as of which the whole cell and body get energy. Thus, messenger RNA and turns it into a series of amino acids. mitochondria are called the powerhouse of the cells. This 19. Somatic Mutation is defined as the alteration in DNA that happens by breaking down food substances such as occurs after conception. It can occur in any of the cell body carbohydrates and fats in the presence of oxygen. The except the germ cells and therefore is not hereditary. ribosomes are non-membrane-bound organelles that help in the synthesis of proteins. 20. The cells of Parenchyma tissue are living and have thin cell walls. It mainly acts as a packing tissue. Collenchyma cells 11. The transformation of the larva into an adult through are also living cells. Its main function is to provide flexibility to drastic changes is called metamorphosis. It is a biological the plants. process that involves sudden and abrupt changes in the body structure of the animal by cell growth and differentiation. It is 21. Mendel's law of dominance states that when parents with generally observed in amphibians and insects. Complete pure contrasting traits are crossed together, only one form of metamorphosis is seen in butterflies. Complete trait appears in the next generation. The hybrid off springs will metamorphosis consists of a very active, ravenously eating exhibit only the dominant trait in the phenotype. larval stage and an inactive pupa stage while the incomplete 22. Cytokinin is a plant hormone. It promotes cell division in metamorphosis has a nymph, which very closely resembles plants. Gibberellins is a plant hormone. It promotes stem the adult. elongation in plants. Auxin is a plant hormone. It promotes 12. In Mendel's experiment, the F1 generation results from the cell elongation in plants. cross-pollination of two-parent (P) plants and contains all 23. Darwin's theory of evolution tells us how life evolved from purple flowers. The F2 generation results from the Self- simple to more complex form. Evolution is a process of change pollination of F1 plants and contains 75% purple flowers and happening over generations. Darwin published his theory of 25% white flowers (PHENOTYPE). The GENOTYPE was 25% evolution with evidence in his book 'On the Origin of Species' pure purple flower, 50% hybrid purple flower, and 25% pure in 1859. The book introduced the scientific theory of evolution white flower. PHENOTYPIC RATIO - 3꞉1 GENOTYPIC RATIO - over the course of generations through the process of Natural 1꞉2꞉1 Selection. 13. The nuclear envelope or nuclear membrane is a two- 24. Sclerenchyma is a simple permanent plant tissue. It layered membrane that wraps around and covers each provides mechanical stiffness and strength to the plants. It is nucleus. It separates the cytoplasm from the nucleoplasm, composed of dead cells i.e non-living cells. which is the fluid in the nucleus. Both plant and animal cells 25. Evolution in its contemporary meaning in biology typically contain the nuclear membrane. Numerous functions are carried out by cells, including the creation of proteins, the refers to the changes in the proportions of biological types in transformation of molecules into energy, and the elimination a population over time. Evolution is the change in of waste products. the characteristics of a species over several generations and relies on the process of natural selection. Evolution relies on 14. Osmosis is the process by which solvent molecules there being genetic variation? in a population which affects move through a semi-permeable membrane from a solution the physical characteristics (phenotype) of an organism. 4 26. Analogous organs have similar functions but different Dominance, Law of Segregation, Law of Independent origins. These are developed in widely different organisms Assortment phylogenetically due to similar habitats and modes of life, 34. Plantae is a taxonomic group that includes land plants e.g., wings of insects, birds and bats, eyes of octopus and and green algae. Kingdom Plantae includes multicellular, mammals. (mostly) autotrophic eukaryotes that (usually) 27. Human genetics can be traced back conduct photosynthesis. to African origin. Paleontological and genetic 35. Gene mutation is caused by the change in the sequence of evidence indicates that modern humans originated in Africa nitrogenous bases. Gene Mutation is a change in one or more within the past 300 thousand years and spread across the genes. It is caused by the change in one or more nucleotides globe within the last 100 thousand years. Therefore, modern of DNA. humans have continuously inhabited the African continent 36. Mutation is a change in a DNA sequence. It can be a result longer than any other region. of DNA copying mistakes made during cell division, exposure 28. The cell wall is a characteristic structure of fungi and is to chemicals called mutagens, exposure to ionizing composed mainly of glucans, chitin, and glycoproteins. As the radiation, or infection by viruses. It is the basic source components of the fungal cell wall are not present in humans, of biological diversity. this structure is an excellent target for antifungal therapy. 37. Genes are functional units of heredity as they are made of 29. DNA. The chromosome is made of DNA containing many If a cross is carried out between a tall parent with violet genes. Every gene comprises a particular set of instructions for flowers (TtWW) and a short parent with white flowers (ttww), a particular function or protein-coding. Speaking in usual the progeny obtained is TtWw (8) ꞉ ttWw (8). terms, genes are responsible for heredity. There are about 30000 genes in each cell of the human body. DNA present in the gene comprises only 2 percent of the genome. 38. A variant form of a gene is known as an allele. Some genes exist in several distinct versions, all of which are found at the same genetic locus on a chromosome. 39. Men determine the sex of a baby depending on whether 30. their sperm is carrying an X or Y chromosome. An X To understand the idea of the purity of gametes, a chromosome combines with the mother's X chromosome to monohybrid cross is taken. A monohybrid cross between pea make a baby girl (XX) and a Y chromosome will combine with plant-bearing axial flowers (AA) and plant-bearing terminal the mother's to make a boy (XY). flowers (aa). In hybrid F1, two types of male and female 40. Chromatin Material is a complex of DNA, histones, and gametes are formed in equal quantity. non-histone proteins that make up the genetic material in the nucleus of a non-dividing cell. It is organized into two types of chromatin꞉ Euchromatin is less condensed and contains actively transcribed genes. Heterochromatin is highly condensed and contains inactive genes. 41. Males have a single X and a single Y chromosome. Females can have only XX. Females will have defects related to the only X chromosome. 42. Ribonucleic acid is a polymer of nucleotides that is made up of a ribose sugar, a phosphate, and bases such as adenine (A), guanine (G), cytosine (C), and uracil (U). It has various biological roles in coding, decoding, regulation, and expression of genes. 31. The phenotypic ratio in the F2 generation is 9 ꞉ 3 ꞉ 3 ꞉ 1. In the F2 generation of Mendels dihybrid cross, the phenotypic 43. Differentiation in organisms leads to a more complex ratio is 9꞉3꞉3꞉1 but here 9 and 1 represent the parental types origin, involving the transformation of cells into a more i.e., they show the parental phenotype but 3 and 3 represent specialized type during the development of multicellular the recombinants i.e., showing one character of one parent organisms. This process is driven by factors like adult stem and the other character of another parent. So, the phenotypic cells and antigen exposure, resulting in fully differentiated ratio of recombinants is 3꞉3 i.e., 1꞉1. daughter cells. Terminal differentiation, where precursor cells cease division, and dedifferentiation, the integration of 32. Chlamydomonas reinhardtii, a unicellular, photosynthetic cellular processes, are also pivotal aspects of this biological green alga in the Chlamydomonadaceae, has never had a phenomenon. multicellular ancestor yet is closely related to the volvocine algae, which express multicellularity in colonies of up to 44. Genes carry the information that determines your traits 50,000 cells. (say꞉ trates), which are features or characteristics that are passed on to you — or inherited — from your parents. Each 33. Gregor Mendel, through his experiments on pea plants, cell in the human body contains about 25,000 to 35,000 discovered the fundamental laws of inheritance. He genes. DNA, or deoxyribonucleic acid, is the hereditary deduced three laws from his experiments and these laws are material in humans and almost all other organisms. Nearly applicable when parents are pure breeding. The three laws of every cell in a person's body has the same DNA. inheritance proposed by Mendel include꞉Law of 45. The mechanism of inheritance where germ cells take one chromosome from each pair and combine to restore the 5 normal number of chromosomes in the progeny is explained in 54. The main difference between human cheek cells and the results of Mendel's experiments. Genes are present as onion peel cells under a microscope is the presence of a cell units in chromosomes and a germ cell chooses one wall in onion cells, as they are plant cells. Cheek cells, being chromosome from each parent to make a single gene. animal cells, lack a cell wall and plastids, which are present in Mutation, variation in chromosomal number, and speciation plant cells. Both cell types have common organelles like cell can also occur due to environmental factors or genetic membranes, endoplasmic reticulum, and nuclei. Plant cells changes. have a large central vacuole and store starch, while animal 46. Cytoplasm is a rich fluid containing water, enzymes, salts, cells have smaller vacuoles and store glycogen. and proteins, filling cells and enclosed by the cell membrane. 55. The main difference between human cheek cells and It's found in both eukaryotic (organisms with a nucleus) and onion peel cells under a microscope is the presence of a cell prokaryotic (organisms without a nucleus) cells. Glycolysis, the wall in onion peel cells, as they are plant cells. Cheek cells, breakdown of glucose (C6 H12 O6) to pyruvate releasing ATP, being animal cells, lack a cell wall and plastids but share occurs in the cytoplasm. Additionally, cytoplasm holds cell common cell organelles like membranes and nuclei with plant organelles and is crucial for cellular processes, distinguishing it cells. Notably, plant cells have a large central vacuole and as a vital cellular component. storage material as starch, whereas animal cells have smaller 47. Chlorophyll is a green pigment that is responsible for vacuoles and store glycogen. photosynthesis in plants. Chloroplasts are organelles found in 56. A sexually reproducing organism with chromosome plant cells that contain chlorophyll and are responsible for number 2n=18 will have 16 autosomes. During meiosis, photosynthesis. chromosomes divide into exact halves, resulting in 8 48. Genetic material, either DNA or RNA, contains all autosomes and 1 sex chromosome in each gamete. Thus, the information specific to an organism. DNA, found in the diploid cell will have 16 autosomes and 2 sex chromosomes in nucleus, forms chromosomes and has a double-stranded total. structure made of deoxyribonucleotides. A nucleotide consists 57. Bifurcation is the division of a cell into two identical of pentose sugar, nitrogen bases, and a phosphate group. The daughter cells. Bifurcation theory explains how minor changes statement that DNA is a polynucleotide made of two in a parameter can lead to significant changes in system components is false because a nucleotide has three behavior, crucial for organism function and common in components. biological networks like cell cycle switches. In contrast, 49. A girl child has combination of 44 autosomes + XX fragmentation involves an organism breaking off and chromosomes. XX denotes the sex chromosomes of the girl regrowing into new organisms, while regeneration allows an child. Typically, human females have two X chromosomes organism to regrow lost body parts, such as octopi regrowing while males possess an XY pairing. Human females are arms. homogametic i.e., they produce same type of gametes with 58. Cloning is the process of generating a genetically identical one X chromosome. copy of a cell or an organism, involving the generation of an 50. During Meiosis, the chromosome count in the daughter exact copy of another living part or a complete organism. It cell is halved, making it a Reduction division. JB Farmer and occurs naturally when a cell replicates itself asexually without Moore introduced the term Meiosis in 1905, occurring genetic alteration or recombination. IVF, on the other hand, is exclusively in reproductive cells. A diploid cell divides into four an assistive reproductive technology involving egg and sperm haploid cells through two phases꞉ Meiosis-I, where to create an embryo. Fructification and regeneration involve chromosomes are halved, and Meiosis-II, where there's no fructifying and restoring damaged or missing parts, reduction in chromosome number. respectively. 51. The main difference between human cheek cells and onion 59. Cro-Magnon, recognized as belonging to Homo sapiens, peel cells under a microscope is the presence of a cell wall in was discovered in 1868 at a rock shelter site near Les Eyzies, onion peel cells, as they are plant cells. Cheek cells, being France. This significant fossil represents one of the first to be animal cells, lack a cell wall and plastids, which are present in identified within our species. In contrast, Homo Ergaster is an plant cells. Both cell types share common organelles like cell extinct archaic human species from the Early Pleistocene in membranes, endoplasmic reticulum, and nuclei. Cheek cells Africa, and Neanderthals, another extinct archaic human appear irregular in shape, while onion peel cells are generally species or subspecies, inhabited Eurasia until about 40,000 rectangular. years ago. 52. 60. Ionising radiation damages the genetic material (DNA) in A DNA molecule is made up of two long polynucleotide living cells by affecting atoms, posing health risks through strands forming a double helical structure (double helix) just tissue and DNA damage. This occurs through direct action, like a spiral staircase. where alpha particles, beta particles, or x-rays break DNA's base pairs, and indirect action. DNA, discovered by James 53. Two alleles are brought together during gamete formation꞉ Watson and Francis Crick, is vital for organism development This is incorrect as per the law of segregation, which states and function, structured as a double helix of polynucleotide that a pair of alleles separate during meiosis resulting in each chains. gamete containing only one copy of an allele. This ensures genetic diversity and maintains the stability of the species' DNA. 6