Students can refer to the following solutions given below for Class 10 Nature and Science Textbook Genetics and Evolution based on the latest syllabus and exam pattern issued by Maharashtra Board. Our subject experts have prepared these questions and answers for grade 10 students. It covers all the topics in the textbook so that students can self-assess all the important topics and be well prepared for the exam.
Below we have provided the Lesson 10 Genetics and Evolution Science Notes and Answers which will help the students to complete the entire syllabus and practice the textbook questions and answers given here along with the answers. You can download it in PDF format and score high on the exam. You should go through all the 10th class heredity and evolution answers given below thoroughly so that you can score higher in the exam.
Points to Remember About Inheritance and Evolution:
- Inheritance is the passing of biological traits from one generation to another through genes.
- Johann Gregor Mendel was the forerunner of modern genetics. From about 1886, it took him a long time to understand the conclusions of his research on heredity.
- In 1901, the reasons behind sudden changes were understood thanks to Hugo de Vries' catastrophe theory.
- Meanwhile, in 1902, Walter and Sutton observed paired chromosomes in grasshopper cells; until then no one knew.
- When it was proved that genes were passed on through chromosomes, research began to move in the direction of finding the nature of the genetic material.
- In 1944, a trio of scientists Ostwald Avery, Mclyn McCarthy, and Colin MacLeod used it to demonstrate that all living organisms, except viruses, have DNA as their genetic material.
- In 1961, French geneticists Francois Jacob and Jack Monad proposed a model for the process of protein synthesis from DNA in bacterial cells. He helped discover the genetic code hidden in DNA.
- Recombinant DNA technology appears and is widely used in the field of genetic engineering.
- The science of genetics can be used in the diagnosis, treatment and prevention of inherited diseases, in the production of plant and animal hybrids, and in industrial processes using microorganisms.
Maharashtra Class 10 Solutions Chapter 2 Chapter 1 Genetics and Evolution
Question 1: Complete the diagram below
Question 2. Read the following statements and justify them in your own words with appropriate examples.
a. Human evolution began about 7 million years ago.
- Human evolution, or humanization, is a slow and gradual process of biological change from the most primitive human ancestors to the emergence of the species we know today, Homo sapiens.
- The process began on the African continent about 5 to 7 million years ago, when a common ancestor emerged between humans and chimpanzees.
- Before humans came along, there were many species that are now extinct, yet they shared many physical, biological, and behavioral similarities.
- Human evolution began when primate populations in northwestern Africa split into two independently evolving lineages: one stayed in the trees while the other migrated to the plains.
- As a result of environmental stress, descendants of this last lineage learned to stand on the front legs, freeing the hind legs, which later became gripping hands.
- Thanks to Charles Darwin's research and the emergence of the theory of the origin of species, it replaced creationism, or spontaneous generation, as the greatest explanation of human origins.
b. Geographic and reproductive isolation of organisms gradually leads to speciation.
answer: The emergence of new species and animals is the result of evolution. A species is a group of organisms that can produce fertile individuals through natural reproduction. Each species grows under specific geographical conditions. They vary in food, habitat, reproductive capacity and time of day. However, genetic variation is what causes new species to emerge from previous ones. In addition, geographic and reproductive changes are also responsible. Likewise, geographic or reproductive isolation can lead to speciation.
Speciation is the process by which groups of organisms that are geographically or ecologically separated from their original population are isolated and differentiated enough to become new species. The gene pool of each species maintains its integrity due to the presence of biological barriers that ensure reproductive isolation. Mechanisms of reproductive isolation (MAR) prevent gene flow between populations belonging to different species. Pregothic segregation mechanisms are time, space, behavioral or other limitations that prevent the formation of fertilized eggs
c. The study of fossils is an important aspect of the study of evolution.
answer:Fossils provide paleontological evidence for evolutionary processes.Due to some natural disasters, living things were buried in ancient times.Imprints and remains of these creatures are still preserved underground. Hot lava can also trap some mobs or their imprints. All of these strata formed fossils.Studying fossils helps researchers understand the characteristics of organisms that existed in the past.Carbon dating also helps determine the exact age of the fossil. Fossils are obtained at certain depths according to the structure of the Earth's crust.The oldest are acquired at depth, while the relatively new ones occupy the upper surface. Thus, invertebrate fossils have been found in the very old Paleozoic era. Later, fossils of fish, amphibians and reptiles were seen. The Mesozoic was dominated by reptiles, and the Cenozoic was dominated by reptilesAge indicates the presence of mammals.research in this wayFossils reveal secrets of evolution.
d. There is evidence that there is a deadly science among chordates.
answer:Fetal science or embryology is used as evidence for evolution. Comparative studies of vertebrate/chordate embryos have shown that they share many similarities at an initial stage that gradually decreases. This similarity in embryonic development represents a common origin of organisms
3. Complete the statement by selecting the correct option from the brackets. (gene, mutation, translocation, transcription, stepwise evolution, addition)
a. The cause-and-effect relationships behind sudden changes are understood thanks to the principle of Hugo de Vries.
b. George Beadle and Edward Tatum provided evidence for the fact that protein synthesis occurs via -.
c. The transfer of information from the DNA molecule to the mRNA is called the ----- process.
d. Evolution means—————.
e. Existence of vestigial organs in the human body—evidence of evolution.
a. Understand the cause-and-effect relationships behind sudden changes due tomutationPrinciples of Hugo de Vries.
b. Evidence for the fact that protein synthesis occursrootCourtesy of George Biddle and Edward Tatum.
c. The transfer of information from DNA molecule to mRNA is calledtranscriptionprogram.d. means of evolutiongradually develop.
e. Residual organsAdd toExistence in humans is evidence of evolution.
4. Write short notes based on information you know.
answer:Lamarck proposed that the activities of living organisms are responsible for theirevolution. Additionally, he said the giraffe's neck becomesDue to browsing the leaves of tall plants are too longlengthened the necks of generations; as,The blacksmith's shoulders became very strong, becauseFrequent hammering movements. bird wings likeOstriches and emus are weakened by uselessness. legFrom birds such as swans and ducks have become usefulSwimming is for living in water, and snakes are losing themLegs modify their bodies for digging habits.All these examples are of the "acquired sign" type,Passed down from generation to generation. This isthe theory of inheritance known as acquired traits orLamarckism.
b. Darwin's theory of natural selection.
answer:Darwin published aA book called The Origin of Species. In explaining this concept, Darwin said everythingBiomass multiplication. All living things compete with each other in life—- threatening manner. Only those exhibited creatures will participate in this contestChanges necessary to win the competition. In addition, however, natural selectionIt also plays an important role as nature selects only those organisms that are capable of livingThe rest perish. Maintained and selected organisms can reproduce, therebylead to new species with their own specific characteristics. Darwin's theory of natureChoice has long been widely accepted.
answer:Embryology is the study of the formation and development of embryos and fetuses. Embryology is used as one of the evidences of evolution. Comparative studies of vertebrate embryos have shown that they have a great similarity in the initial stage, which gradually decreases. This similarity in embryonic development represents a common origin of organisms.
answer:Evolution is a gradual change in an organism over a long period of time. This isA very slow process of achieving the development of an organism. all stagesIn the changes that occur in various components, from stars and planets in space toThe Earth's biosphere should be included in the study of evolution. formation of new manSpecies change due to a particular property of an organism over several generations, e.g.Response to natural selection is called evolution
e. Affiliate Links.
answer:Some plants and animals exhibit some morphological traits that allow them to be identifiedRefers to two distinct groups; hence they are called "connecting links". For example in PeripatusFeatures such as segmented body, thin cuticle, and accessory pods are present.Likewise, these animals exhibit tracheal breathing and a similar open vasculaturearthropods. This suggests that Peripatus was the link between annelids and arthropods
Likewise, the platypus lays eggs like reptiles but shows a relationship with mammalsAlso due to the presence of mammary glands and hair
5. Define inheritance. Mechanisms that explain genetic change.
answer:Inheritance is the passing of biological traits from one generation to another through genes. This genetic information is stored in a molecule called DNA. During reproduction, a child receives genetic information in the form of DNA from both parents. 50% of the genetic information comes from the father's DNA, and the other 50% comes from the mother's DNA. Because of this, the child is very similar to his parents and has features similar to both of them. Common inherited traits are curly hair, special types of earlobes, ear hair, etc.
6. Define residual organs. write namehuman remainscorpses and write down the names of thoseanimals with the same organsfunctional.
answer:Useless organs that are degenerated or underdeveloped in organisms are called degenerative organsorgan. In an organism, the sudden development of new tissues or organs for lifeEnvironmental change is impossible. Instead, existing organs change gradually.The appendix, which is useless to humans, is also usefulA fully functional organ of a ruminant. Similarly, musclesearlobe useless to humansThe monkey moved its ears. various cluesCoccyx, wisdom teeth, and body organsHair exists in the human body.
7. Answer the following questions.
a. How genetically changedResponsible for evolution?
answer:Inheritance is the passing of biological traits from one generation to another through genes.Inheritance causes variations in offspring that may or may not be beneficial to the organism. Useful attributes help them survive and reproduce. So it's a form of natural selection. – Natural selection of genetic variation contributes to the evolution of species.
b. Explain the creative processcomplex protein.
answer:These proteins are synthesized from DNA via RNA. This is calledas "central dogma". mRNA is produced based on the nucleotide sequence on DNA. only oneTwo strands of DNA are used in this process. They are the three steps in protein production
- Transcript:Nucleotide sequence in mRNA seIt is always complementary to the DNA strand used for synthesis. Beside this there isUracil in RNA replaces thymine in DNA. This RNA synthesis process is called transcription.
- mRNA produced in the nucleus enters the cytoplasm. It brings encoded information from DNA. The message contains the amino acid code. Each amino acid consists of three nucleotides. It's called a "triple codon".
- translate:Each mRNA consists of thousands of triplet codons. According to the information on the mRNA, amino acids are acquired by tRNA. To do this, the tRNA has an "anticodon", which has a complementary sequence to the codon on the mRNA. This is called "translation".
- Translocation:The amino acids brought in by tRNA are linked together by peptide bonds with the help of rRNA. During this process, the ribosome continues to move a distance of one triplet codon from one end of the mRNA to the other. This is called "translocation". So many chains come together to form complex proteins.
c. explain evolution andProvide evidence to support this.
answer:According to the theory of evolution, the earliest living matter was protoplasm originating from the ocean.Single-celled organisms gradually emerged from it. These single-celled organisms change, causing them to evolve into larger, more complex organisms.All evolutionary changes are very slow and gradual, taking about 300 million years.Different types of organisms have evolved as changes and development in organisms have been driven holistically and multidimensionally.Hence, this whole evolutionary process is called organized and gradual.The diversity of plants and animals arises from ancestors with different structural and functional organizations during evolution.
The evidence here refers to the evidence of evolution.The evidence for this is as follows:
- Morphological evidence
- anatomical evidence
- residual organs
- pathological evidence
- connection link
- Embryological Evidence
d. Explain the importance with suitable examplesfrom anatomicalevidence of evolution.
answer:anySuperficial similarities between peopleA hand, a cat's front leg, a whale's finand bat patagium. Similarly, useEach of these structures is different
the corresponding animal. However, there are
Similarities in bone structure and
Bone joints in the organs of each of them
animal. This similarity suggests
these animals can have something in common
e. Define fossils. Explain the importanceFossils as evidence of evolution.
answer:The remains and footprints of buried organisms are still preserved underground. They are called fossils. The study of fossils is an important aspect of the study of evolution.
- Carbon consumption in animals and plants stops after death, only the C-14 decomposition process continues.
- In the case of plant and animal carcasses, the ratio between C-14 and C-12 does not remain constant but changes because C-12 is not radioactive.
- The time after a plant or animal dies can be calculated by measuring the radioactivity of C-14 and the ratio of C-14 to C-12 present in their body.This is carbon dating. It is used to determine the age of human fossils and manuscripts.
- Once the age of a fossil is determined, it is easy to extrapolate information about other pre-organisms.Vertebrates appear to have slowly evolved from invertebrates.
F. writing evolutionary historymodern man.
answer:Evolutionary history of modern humans:
- About 7 million years ago, dinosaurs disappeared completely. At that time, monkey-like animals appeared, more or less similar to modern lemurs.
- The tails of these monkey-like animals disappeared about 4 million years ago. Due to enlarged brains and improved hands, ape-like animals emerged, which later evolved into gibbons and orangutans.
- Gorillas and chimpanzees evolved from gibbons and orangutans about 2.5 million years ago.
- About 2 million years ago, the first human-like animals had an upright posture and the use of both hands.
- The monkey Ramapithecus was recorded as the first humanoid. Later the monkey grew up and became smarter.
- About 2 million years ago, skilled humans evolved, and about 1.5 million years ago, humans evolved an upright posture and gait.
- Neanderthals are believed to be the first sapiens.
- The Cro-Magnons evolved about 50,000 years ago, and the subsequent evolution was even faster than the previous one.
1. Introduce the person
Evolution using a different computer
software and schedule a group
discuss in class
Answer: answer yourself
(i) Evolutiion is defined as the gradual changes occuring in living organisms over a long duration. (ii) It is a slow-going process through which development of organisms is achieved. (ii) Evolution is thus the formation of new species due to changes in specific characters of living organisms.What are the important topics in heredity and evolution class 10? ›
- Mendel's pea experiment.
- Sex determination.
- Acquired and Inherited traits.
- Homologous and Analogous organs.
- Human evolution.
Genetics is the branch of biological sciences which deals with the study of genes, genetic variation, and heredity in living organisms. Heredity is the transfer of characters from one generation to the other.What are the topics of genetics and evolution? ›
Evolutionary genetics is the study of how genetic variation leads to evolutionary change. It includes topics such as the evolution of genome structure, the genetic basis of speciation and adaptation, and genetic change in response to selection within populations.