Genetics and Evolution - long answer questions

Evolution (NEET Syllabus): Origin of life; Biological Evolution and Evidences for Biological Evolution from Paleontology, Comparative Anatomy, Embryology and Molecular Evidence; Darwin’s Contribution, Modern Synthetic theory of Evolution; Mechanism of Evolution-Variation (Mutation and Recombination) and Natural Selection with examples, types of Natural Selection; Gene Flow and Genetic Drift; Hardy-Weinberg’s Principle; Adaptive Radiation; Human Evolution. 

EVOLUTION (Genetics and Evolution)

Theoretical Questions - TQ 2 (Q. No. 7-11)
Long Answer Type Questions
Question.7: How does industrial brownish explain Darwin's theory of Natural Selection?
Question.8: What are fossils? Mention any two way in which the study of fossils support biological evolution of an organism.

Very Long Answer Type Questions
Question.9: Explain Darwinism and criticism.
Question.10: Explain in brief regarding origin of source of variation.
Question.11: Explain in brief regarding human evolution.

Answer 7: In England, it was observed before industrialization that white-winged moth (Biston betularia) were more in number than dark-winged moth. But the situation became reversed after industrialization. It was argued that predator will spot and pick a moth (Biston betularia) against a contrasting background. In pre-industrialization, the tree trunk was covered by white lichens and on white background dark colour moth can be picked up. The situation changed during industrialization, the tree was covered by dar, dust, coal particles and become dark on which white moth can easily be picked up. Thus, it is a case of natural selection which built pressure on population and some members are selected for evolution.

Answer 8: The remains or evidences of pre-historic life is called fossil.
Two ways in which study of fossils support biological evolution:
(i) The study of Archaeopteryx reveals that birds have evolved from reptile, so fossil provide evidence for evolution.
(ii) Phylogeny can be reconstructed from the fossils.
(iii) The habitat and behaviour of extinct organisms can be inferred from well preserved fossils.

Answer 9: The Great criticizer Hugo De Vries criticized Darwinism by the following points:
1. Great weakness: He was unable to explain the cause, origin and inheritance of variations.
2. Raw Material for evolution: He regarded all small and continuous variations, which may be acquired by organism during their life time due to environmental effect but somatic ones never play this role.
3. Theory of pangenesis: As it is cleared that Darwin was failed to explain the origin of variations at genetic level as well their transmission to next generation. In 1868, Darwin put forward his own theory of inheritance, the Theory of pangenesis. According to this theory, every organ of the body produce minute hereditary particles, called Pangenesis or Gemmules e.g., live Gemmules from liver, leg Gemmules from leg, and so forth. He thought the Gemmules were carried through the blood form every organ of the body and were collected together into the gametes.
4. Certain useful or harmful variations are brought about by mutation (Sudden changes in genetic material) and Darwin knew about these sudden changes (Mutation) and called these sports, but Darwin either ignored these observations or kept silence.
5. The variations of Darwin originated by natural selection are gradual (not in single step) and certain variations such as electric organ of Torpedoes, light producing organs of luminescent organism (Glow worm) etc., are functional and useful only in their perfected state (in fully developed state not in under developed state) and could not be originate through natural selection while only possible through mutation.
6. There are some examples of overgrowth of useful cousins beyond the limit of usefulness and bring down extinction of some species rather than evolution, and it is said clearly that it is not possible through adaptation and natural selection e.g., Antlers of Iris elk, teeth of Sweedolon.
7. Darwin was also unable to explain how does set of coordinated organ evolved through natural selection.

Answer 10: Five factors regarding origin of source of variation are as follows:
1. Gene migration or Gene flow
If the migrating individuals breed within the new population, the immigrants will add new alleles to the local gene pool of the host population called gene migration
(Gene flow).Sometimes two populations of a species which were separated, come close due to migration. The genes of two populations mix through breeding and the result causes variations in the offspring. The random introduction of alleles into the recipient population and their removal from donor population affects the allelic frequencies of both the populations. Gene flow decreases the genetic differences between populations.
2. Genetic Drift
The random changes in the allele frequency occurring by chance alone are called genetic drift.
3. Mutation
According to Hugo De Vries, it is a sudden heritable changes. Single step large mutation (saltation) brings speciation.
4. Genetic Recombination
Crossing over or independent segregation during meiosis followed by random fertilisation are referred to as genetic recombination.
5. Natural Selection
Organisms which are better adapted to the environment survive and reproduce. It is of 3 types:
(a) Stabilizing Selection (centripetal selection)
This selection operates in stable environment. In this process extreme individuals from the two ends of the phenotypic distribution are eliminated. Stabilizing selection does not promote evolutionary change that leads to speciation, but tends to maintain phenotypic stability within the population over generations. It removes deleterious genotypes from the population.
(b) Disruptive selection
This selection operates in response to gradual changes in environmental conditions. It works by constantly removing individuals from one end of the phenotypic distribution. Therefore, average value of fitness is coherently shifting towards the other end of the phenotypic distribution.
(c) Disruptive selection (centrifugal selection)
This is a rare selection, but very important in bringing about evolutionary change. This process operates in the changing conditions within an environment (heterogeneous environment) which increases the competition in the population. This can split the population into two or more sub populations called Species populations. It is also called as Adaptive radiation.

Answer 11: Humans were developed from ape like ancestors. Human beings belong to order Primates, sub order Anthropoidea, super family hominoidea, family Hominidae and sub family Homininae.
The term "anthropoid apes" is used for common ancestors of humans, apes and monkeys.
Humans, apes are their common immediate ancestors.
Human ancestry:
www.indiastudysolution.com - image showing Human Ancestry

About 15 million years ago, primates called Dryopithecus and Ramapithecus were lived on earth.
Dryopithecus was more ape-like. Ramapithecus was more man-like.
It is believed that most of the human evolution occurred in Ethiopia, Kenya, Tanzania (East Africa). Fossils of man like bones were discovered in Ethiopia and Tanzania, based on these fossils it is believed that man like primates walked in Eastern Africa about 3-4 million years ago. These were approximately four feet tall and walked up right.

Genetics and Evolution - More Practice and Sample Questions with Answers 
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Genetics and Evolution - short answer questions

Evolution (NEET Syllabus): Origin of life; Biological Evolution and Evidences for Biological Evolution from Paleontology, Comparative Anatomy, Embryology and Molecular Evidence; Darwin’s Contribution, Modern Synthetic theory of Evolution; Mechanism of Evolution-Variation (Mutation and Recombination) and Natural Selection with examples, types of Natural Selection; Gene Flow and Genetic Drift; Hardy-Weinberg’s Principle; Adaptive Radiation; Human Evolution.  

EVOLUTION (Genetics and Evolution)

Theoretical Questions - TQ 1 (Q. No. 1-6)

Very Short Answer Type Questions

Question.1: Define fossils.
Question.2: Write name of two Vestigial organ of human.
Question.3: Define Genetic Drift.
                   Or,
The random changes in the allele frequency occurring by chance alone are genetic drift.

Short Answer Type Questions

Question.4: What is meant by analogous organ? Taking a suitable example, explain how they support the theory of organic evolution.
Question.5: What is speciation?
Question.6: Explain Disruptive Nature of selection?

Answer 1: Fossils are preserved remains, traces or prints of organism that lived in past.

Answer 2:
(i) Vermiform appendix, (ii) Tail vertebrae.

Answer 3:
Genetic Drift: (Sewall Wright effect)
"Drift is a binomial sampling errors of the gene pool." Sampling errors (error in gene pool of next generation mean gametic error) by chance often lead to the elimination of certain alleles and fixation of other and it ultimately cause the loss of genetic diversity.
                 Or,
The random changes in the allele frequency occurring by chance alone are called genetic drift.

Answer 4: The organs which have different developmental origin and structural design but perform similar functions are called analogous organs. The wings of birds and insects are analogous organs indicating that they have different ancestors but show a convergent evolution.

Answer 5:
Speciation is formation of one or more new species from pre-existing species. It can be of two types:

Allopatric speciation
When a population formerly continuous in a range, splits into two or more geographically isolated population and form new species. Eg. Darwin finches, Marsupial radiation.

Sympatric speciation
When a population reproductively isolated in midst of its parent population and form new species. Sympatric speciation is the formation of a species within a single population without geographical isolation. Ex. Quated example of sympatric speciation comes from polyploidy (when chromosome fails to segregate at meiosis or replicate without undergoing mitosis).

Answer 6:
Disruptive Nature of Selection

Natural selection that favours the extremes of a phenotype in a population. It often operates when an environmental factor shows distinct variations, for example high temperatures in summer and low temperatures in winter with no intermediate forms. In this case the population will be variously adapted to withstand both high and low temperatures.



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NEET, IITJEE, AIPMT, AIEEE, NAT, BITSAT, AFMC, OJEE, KIITEE, COMEDK, JIPMER Practice Questions and Test Series - Physics - Gravitation

 
Physics >> Gravitation

Physics MCQ test series and practice questions from the chapter “Gravitation”. Prepare for IITJEE, NEET, AIPMT, AFMC, MBBS Admission Tests such as Tripura Joint Entrance Exam (TJEE), AIEEE, BITSAT, KEAM - CEE Kerala, AIPVT - All India Pre-Veterinary Test, West Bengal Joint Entrance (WBJEE), Manipal University MBBS Admission Test, Odisha Joint Entrance (OJEE), Bihar PMT, KIITEE, COMEDK - UPCAT, JIPMER MBBS Entrance Exam, Punjab Engineering and Medical Entrance Test, UPCMET, KCET, SRM EEE (SRM Engineering Entrance Exam), Rajasthan Pre Veterinary Test (RPVT), EAMCET, IMS - BHU PMT (Banaras Hindu University Pre Medical Test), UPCPMT, AEEE (Amrita Engineering Entrance), Amrita MBBS & BDS Entrance Exam, VITEEE, AMU MBBS, AP JEE, CMC Vellore Medical Entrance Exam, NAT (National Aptitude Test), ISAT (IIST Admission Test), all national and state level joint entrance tests.

Physics MCQ Test Series and Practice Questions on Gravitation


Syllabus: Kepler’s laws of planetary motion. Laws of Gravitation - the universal law of gravitation. Acceleration due to gravity and its variation with altitude and depth. Gravitational Forces. Gravitational potential energy and Field; Escape velocity, orbital velocity of a satellite. Geostationary satellites. Motion of planets and satellites in circular orbits.

Physics Practice Questions MCQs: Gravitation
Multiple Choice Questions (MCQs) – Set 2 (Q. No. 11 - 20)

Question 11: If a planet consists of a satellite whose mass and radius were both half that of the earth, the acceleration due to gravity at its surface would be:




Question 12: Which of the following graphs between the square of the time period and cube of the distance of the planet from the sun is correct?

www.indiastudysolution.com image


Question 13: Force of gravity is least at
a. The equator                                      
b. The poles
c. A point in between equator and any pole  
d. None of these

Question 14: Which of the following is the evidence to show that there must be a force acting on earth and directed towards the sun?
a. Deviation of falling bodies towards east
b. Revolution of the earth around the sun
c. Apparent motion of the sun round the earth
d. Phenomenon of day and night

Question 15: A particle of mass ‘m’ is kept at rest at a height 3R from the surface of earth, where ‘R’ is radius of earth and ‘M’ is mass of earth. The minimum speed with which it should be projected, so that it does not return back, is -
(g is acceleration due to gravity on the surface of earth)




Question 16: For a satellite in elliptical orbit which of the following quantities does not remain constant:
a. Angular momentum    b. Momentum    c. Areal velocity    d. Total energy







Question 18: The acceleration due to gravity at pole and equator can be related as –
India Study Solution - Free online physics MCQ on Gravitation image


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Units, Dimensions, Measurements and Error Analysis - Physics MCQ test series and practice questions for BTech, MBBS, BDS admission tests

Physics > Units Dimensions Measurements and Error Analysis
Physics MCQ test series and practice questions with solutions on “Units, Dimensions, Measurements and Error Analysis” to prepare for IITJEE, AIPMT other national and state level engineering and medical Joint Entrance Exams, BTech, MBBS, BDS Admission Tests ISAT (IIST Admission Test) and other competitive examinations.

Units, Dimensions, Measurements and Error Analysis for Medical, Engineering Joint Entrance Tests

Syllabus: Units and Dimensions. International System of Units - SI, Fundamental and Derived Units. Dimensional Formulae and Dimensional Equations. Dimensional Analysis and its Applications. Significant figures and rounding off the numbers. Measurement of length, mass, and time. Accuracy, Precision of Instruments and error analysis. 

Physics: Units, Dimensions, Measurements and Error Analysis
Multiple Choice Questions – Set 2 (Q No 11-20)
Question 11: A new unit of length is chosen such that the speed of light in vacuum is unity. What is the distance between the sun and the earth in terms of the new unit, if light takes 8 min and 20 s to cover this distance?
a. 300    b. 400    c. 500    d. 600

Question 12: The dimensional formula for relative refractive index is
a. [M1L1T1]    b. [M0L0T0]
c. [M1L0T0]    d. [MLT-1]

Question 13: The pitch of a screw gauge having 50 divisions on its circular scale is 1 mm. When the two jaws of the screw gauge are in contact with each other, the zero of the circular scale lies 6 division below the line of graduation. When a wire is placed between the jaws, 3 linear scale divisions are clearly visible while 31st division on the circular scale coincide with the reference line. The diameter of the wire is:
a. 3.62 mm    b. 3.50 mm     c. 3.5 mm   d. 3.74 mm

Question 14: Which of the following has the dimensions of pressure?
a. [MLT2]     b. [ML-1T-2]
c. [ML-2T-2]  d. [M-1L-1]

Question 15: Unit of pressure in S.I. system is
a. atmosphere    b. dynes per square cm
c. pascal             d. bar

Question 16: Which of the following is not the unit of surface tension:
a. N/m       b. J/m2
c. kg/s2         d. none of these

Question 17: The focal power of a lens has the dimensions
a. [L]    b. [ML2T-3]
c. [L-1]  d. [MLT-3]

Question 18: A student measures the distance traversed in free fall of a body, initially at rest, in a given time. He uses this data to estimate g, the acceleration due to gravity. If the maximum percentage errors in measurement of the distance and the time are e1 and e2 respectively, the percentage error in the estimation of g is
a. e2 – e1    b. e1 + 2e2            
c. e1 + e2  d. e1 – 2e2                         

Question 19: The density of a cube is measured by measuring its mass and length of its sides. If the maximum error in the measurement of mass and lengths are 3% and 2% respectively, the maximum error in the measurement of density would be
a.12%    b. 14%
c.7%      d. 9%

Question 20: The M.K.S.A. system was first introduced by
a. Archimedes    b. Galileo
c. Newton           d. Giorgi

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