Read and download free pdf of CBSE Class 10 Biology Heredity And Evolution Worksheet Set D. Students and teachers of Class 10 Biology can get free printable Worksheets for Class 10 Biology in PDF format prepared as per the latest syllabus and examination pattern in your schools. Standard 10 students should practice questions and answers given here for Biology in Grade 10 which will help them to improve your knowledge of all important chapters and its topics. Students should also download free pdf of Class 10 Biology Worksheets prepared by school teachers as per the latest NCERT, CBSE, KVS books and syllabus issued this academic year and solve important problems provided here with solutions on daily basis to get more score in school exams and tests
Heredity And Evolution Class 10 Biology Worksheet Pdf
Class 10 Biology students should refer to the following printable worksheet in Pdf for Heredity And Evolution in standard 10. This test paper with questions and answers for Grade 10 Biology will be very useful for exams and help you to score good marks
Class 10 Biology Worksheet for Heredity And Evolution
Question : Define speciation.
Answer : Speciation means origin of new species from the existing one.
Question : How are characters or traits controlled?
Answer : Characters or traits of an organism are controlled by the genes /DNA.
Question : In a beetle population, the number of green beetles is more than blue and red beetles. Give a reason behind this situation.
Answer : Variation/Natural selection.
Question : What is genetic drift?
Answer : The change in the frequency of certain genes in a population over generations.
Question : What is heredity?
Answer : Transmission of characters and traits from one generation to the next.
Question : How many pairs of chromosomes are present in human beings?
Answer : 23 pairs.
Question : Give the respective scientific terms used for studying:
a. the mechanism by which variations are created and inherited, and
b. the development of new type of organisms from the existing ones.
Answer :
a. Heredity
b. Species
Question : Why is the progeny always tall when a tall pea plant is crossed with a short pea plant?
Answer : The trait which represents the tallness in a pea plant is dominant over the another trait, shortness (dwarf).
Question : Human have evolved from chimpanzee. Is it true?
Answer : No, the two species have evolved in separate ways from a common ancestor.
Question : Why is it that asexual reproduction produces exact copies but sometimes minor variations are also seen in next progeny?
Answer : Since no biochemical reaction is reliable, therefore, in copying of DNA, it may cause slight difference which causes these variations.
Question : How can the chromosomes be identified?
Answer : In human beings, the individual chromosomes are identified by their lengths, position of centromere and banding pattern on staining.
Question : No two individuals are absolutely alike in a population. Why?
Answer : All individuals have different kind of DNA. So all individuals are not alike to each other.
Question : What is a gene?
Answer : It is a functional piece of DNA that is responsible for expression of a trait in the organisms.
Question : What indication do we get by reappearance of dwarf plant in F2 generation?
Answer : After obtaining progeny in F2 generation in a dihybrid cross, Mendel concluded that when two pairs of traits are combined in a hybrid, one pair of character segregates independently of the other pair of character.
Question : Name the term used for the traits that are exhibited externally.
Answer : Phenotype.
Question : An organism which is a worm, has very simple ‘eyes’, that are really eye spots which detect light. Name that organism.
Answer : Planaria.
Question : What are fossils? What is their significance in the study of evolution?
Answer : Fossils are impressions of the body/ body parts or the remains of organisms living in the past, which got preserved in sediments of earth.
a. Study of fossils helps in working out evolutionary relationships.
b. Fossils provide one of the most acceptable evidences in support of evolution, because we can study the evolutionary past of individuals in the form of their fossils.
c. Age of fossils can also be found by time dating using isotopes of carbon! carbon dating.
d. By studying fossils occurring in different strata of rocks, geologists are able to reconstruct the time course of evolutionary events.
Question : Write the sex of the baby that inherits Y-chromosomes from the father.
Answer : Male.
Question : What is the phenotypic ratio of a dihybrid cross in F2 generation?
Answer : 9 : 3 : 3 : 1.
Question : When a tall and dwarf pea plant were crossed, Fx showed only tall plants but in F2 generation, some plants were dwarf. What does it mean?
Answer : It means reappearance of the dwarf character, a recessive trait in B’2 generation shows that the dwarf trait/ character was present in individuals of F* but it did not express (due to the present of tallness, a dominant trait / character)
Question : Mendel observed a contrasting trait in relation to position of flowers. Mention the trait.
Answer : Axial flower position (dominant), terminal flower position (recessive).
Question : What is the effect of DNA copying which is not perfectly accurate on the reproduction process?
Answer : It will result in less variations which may further lead to less adaptation to changing environment, thus, giving less chances of survival.
Question : What are the basic events in evolution?
Answer : The changes in DNA during reproduction are the basic events in evolution.
Question : All the variations in a species do not have equal chances of survival. Why?
Answer : Some variations are caused by environmental changes and they do not bring out any change in DNA.Therefore, all the variations do not have equal chances of survival.
Question : What are fossils?
Answer : Preserved traces of living organisms.
Question : How can the chromosomes be identified?
Answer : In human beings, the individual chromosomes are identified by their lengths, position of centromere and banding pattern on staining.
Question : What are analogous organs?
Answer : The organs which have similar functions but different structures are called analogous organs.
Question : How is the age of fossil determined?
Answer : The age of fossil fuels is determined through carbondating or time dating method.
Question : A Mendelian experiment consisted of breeding pea plants bearing violet flowers with pea plants bearing white flowers. What will be the result in Fj progeny?
Answer : All will bear violet flowers.
Question : What is evolution?
Answer : Gradual unfolding of organisms from pre-existing organisms through change is called evolution
Question : Name the plant on which Mendel performed his experiments.
Answer : Garden pea (Pisum sativum).
Question : Give an example where sex determination is regulated by environmental factors.
Answer : In snail, sex is determined by environmental factors (temperature).
Question : When does the process of gene flow take place?
Answer : Gene flow or gene migration takes place in between the populations that are partly but not completely separated.
Question : (a) On what rules inheritance is based?
(b) Is each trait influenced by both paternal and maternal DNA?
Answer :
a. The rules of inheritance is based on the fact that the traits in the progeny are carried out by DNA’s of both the parents (mother and father). These rules are known s ‘Mendel’s Laws of Inheritance’.
The rules are:
(i) Law of dominance,
(ii) Law of segregation, and
(iii) Law of independent assortment.
b. Yes, it is true that each trait is influenced by both paternal and maternal DNA.
Question : The human hand, cat paw and the horse foot, when studied in detail show the same structure of bones and point towards a common origin.
a. What do you conclude from this?
b. What is the term given to such structures?
Answer :
a. They have common origin/ancestory.
b. Homologous organs.
Answer : Mendel observed seven contrasting characters is pea plant. For Ex- flower positionaxial and terminal. seed shape- round and wrinkled.
Answer :
Answer : The idea of tracing the evolutionary relationships is presently known as molecular phylogeny, which focus on identifying the changes occuring in DNA during reproduction. Evolution does not occur because of a single change in DNA or mutation. Organs are complex both structurally and functionally; and are genetically regulated by many genes working together. Evolution occurs in many stages by slow changes in DNA or mutation that accumalate over time. The stages occurring during evolution can thus be identified by different structures formed from common ancestors.
More Question
Q1)Who is known as father of genetics?
Q2)Write the scientific name of the plant on which Mendel carried out his experiment.
Q3)How many chromosomes are present inhuman beings?
Q4)What is the genetic material?what is its importance?
Q5)What are recessive genes?
Q6)What are dominant genes?
Q7)Name the cells which possess half the number of chromosomes in human beings? (hint-germ or reproductive cells)
Q8)State the advantages of sexual reproduction?
Q9)Name any two contrasting characters noticed by Mendel in the garden pea plants.
Q10)State the ratio of plants produced in the monohybrid cross in the F1 and F2 generation?
Q11)Where are genes located? What is the chemicals nature of genes?
Q12)How is the sex of a newborn child determined inhumans?
Q13)Why did Mendel choose pea plant for his experiment?
14)Give reasons why acquired characters are not inherited.
Q15)What are the functions played by DNA?
Q16)What observations did Mendel make during his experiments?
Please click the below link to access CBSE Class 10 Biology Heredity And Evolution Worksheet Set D
Click for more Biology Study Material ›
CBSE Class 10 Science Carbon and its Compounds Worksheet |
CBSE Class 10 Biology Our Environment Management Of Natural Resources Worksheet Set A |
CBSE Class 10 Biology Our Environment Management Of Natural Resources Worksheet Set B |
CBSE Class 10 Biology Management Of Natural Resources Worksheet Set A |
CBSE Class 10 Biology Management Of Natural Resources Worksheet Set B |