ORIGIN-AND-EVOLUTION-OF-LIFE-QUIZ-5

BIOLOGY ORIGIN AND EVOLUTION OF LIFE QUIZ-5

Dear Readers,

NEET is the most famous and important medical entrance examination held in our country. This exam is an objective type, an offline test which includes 4 sections namely– Physics, Chemistry, Botany, and Zoology. The maximum marks that can be scored are 720 marks and have 180 questions. About half of the paper consists of questions from Biology, as the NEET exam essentially focuses on capacitating students to go for seats in medical courses. One of the most significant and crucial sections in the NEET exam is of Biology. It comprises of theories, descriptions, discoveries, diagrams, definitions, explanations of differences, and relations. The majority of the topics covered in the NEET syllabus are from the NCERT syllabus of Class 11 & 12 and other related sources become part of the rest of the syllabus. Clear Exam curates a list of articles selected by professionals who recommend the highly vital topics for NEET exams. The table below takes you directly to the respective topic where the in-depth article and the MCQs are available for an easy and productive learning experience. Prior to solving NEET question papers or practicing mock tests, you must ensure to study the basic concepts in NEET and practice a few sample questions related to this exam. Students will be covered for all their studies as the topics are available from basics to even the most advanced..

Q1. An evolutionary process, giving rise to new species adapting to new habitat and ways of life is called

•  Adaptive radiation
•  Adaptation
•  Convergent evolution
•  Microevolution

Solution
(a) When a group of organisms shares a homologous structure, which is specialized to perform a varity of different functions, it shows adaptive radiation, which represents evolution of new forms in several directions from the common ancestral type (divergence).

Q2.Genetic equilibrium means

•  Gene pool remains constant
•  Phenotypes remains constant
•  Migration of a species into new area
•  Immigration of species

Solution
(a) Gene pool remain constant. Hardy-Weinberg Principle It was proposed by GH Hardy an English mathematician and W Weinberg a German physician independently in 1908 (i) It describes a theoretical situation in which a population is undergoing no evolutionary change. This is called genetic or Hardy-Weinberg equilibrium (ii) It can be expressed as p^2+2pq+q^2=1 or(p+q)^2=1 (iii) Evolution occurs when the genetic equilibrium is up set (evolution is a departure from Hardy-Weinberg equilibrium principle) The sum of total of Allelic frequency (p+q)is=1 p^2+2pq+q^2or (p+q)^2 Where, p^2=% homozygous dominant individuals p= frequency of dominant allele q^2=% homozygous recessive individuals q= frequency of recessive allele 2pq=% heterozygous individuals Realize that (p+q)^2=1 (three are only 2 alleles) p^2+2pq+q^2=1 (these are the only genotypes)

Q3.  Which of the following sets contain only homologous organs?

•  Whale’s flipper, horse’s forelimb, Human hand
•  Wings of butterfly, crow and insect
•  Horse’s forelimb, insect wing, human hand
•  Vermiform appendix, body hair and patella

Solution
(a) Organs that have developed from the same embryonic cell and thus have similar internal organization are called homologous organs. These organs may or may not have similar functions, e.g., whale’s flipper, forelimb of horse, human hand.

Q4. The age of fossils or dating of fossils can be best estimated by

•  Radioactive carbon (C¹⁴) dating method
•  Radioactive nitrogen method
•  Radioactive clock method
•  None of the above

Solution
(a) Radioactive carbon (C^14) dating method is used to study the age of fossils or dating of fossils.

Q5.If frequency, of ‘A’ allele is 0.4 than, find out the frequency of ‘B’ allele and heterozygous genotype in a random mating population at equilibria

•  0.6 and 0.24
•  0.6 and 0.96
•  0.6 and 0.48
•  0.6 and 0.50

Solution
(c) HW Principle = p + q =1 p^2+2pq+q^2=1 Here, p = A and q is = B Allele frequency of B = 1-0.4 = 0.6 Allele frequency of heterozygous is = 2×0.6×0.4 =0.48

Q6. ‘Population tends to increase geometrically, while food supply increases arithmatically’. This concept was put forward by

•  TR Malthus
•  Struart Mill
•  Charles Darwin
•  Adam Smith

Solution
(a) Population tends to increase geometrically while food supply increases arithmetically. This concept was put forward by TR Malthus

Q7.Which one is linked to evolution?

• Extinction
•  Competition
•  Variation
•  Reproduction

Solution
(c) It is difficult to find out any of the two individuals alike. Even the progeny of the same parents are not exactly alike in all respects. These differences are known as variations. Without variations changes could not occur and there will be no possibility of evolution to occur certain variations, which once appeared in the parent generation, continue to appear in the progeny generation after generation.

Q8.Weismann cut off tails of mice generation after generation but tails neither disappeared nor shortened showing that

• Lamarck’s theory was wrong
•  Darwin’s theory was wrong
•  Synthetic theory was wrong
•  Mutational theory was wrong

Solution
(a) Theory of continuity of germplasm was give by August Weismann (1834-1914). Theory of continuity of germplasm by August Weismann (1834-1914). A German biologist, was the main opposer of the inheritance of acquired characters. He put forward the theory of continuity of germplasm. According to Weismann, the characters influencing the germ cells are only inherited. There is a continuity of germplasm (protoplasm of germ cells) but the somatoplams (protoplasm of somatic cells) is not transmitted to the next generation. Hence, it do not carry characters to the next generation. Weismann cut off the tails of rats for as many as 22 generations and allowed them to breed, but tailless rats were never born

Q9.Amoug the human ancestors, the brain size was more than 1000 cc in

•  Homoneanderthalensis
•  Homoerectus
•  Ramapithecus
•  Homo habilis

Solution
(a) The cranial capacity of Homoneanderthalensis was about 1450 cc. roughly equal to that of Modern man.

Q10. In plants like Acacia, the leaves are compound but their seedlings possess simple leaves. This phenomenon can be explained by

•  Adaptive radiation concept by Darwin
•  Theory of inheritance of acquired characters by Lamarck
•  Recapitulation concept by von Baer
•  Mutation theory by de Vries

Solution
(b) Embryological Evidences in Plants Plants like Acacia, the leaves are compound but their seedling have simple leaves. This suggest their evolutionary relationship (biogenetic law), Haeckel’s biogenetic law states that ontogeny repeats phylogeny. Ontogeny is the life history of an organism, while phylogeny is the evolutionary history of the race of that organism. In other words an organism repeats its ancestral history during its development