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All questions of Evolution for Grade 12 Exam
Fossils are generally found in:- a)Metamorphic rocks
- b)Igneous rocks
- c)Sedimentary rocks
- d)Any type of rock
Correct answer is option 'C'. Can you explain this answer?
Fossils are generally found in:
a)
Metamorphic rocks
b)
Igneous rocks
c)
Sedimentary rocks
d)
Any type of rock
|
Geetika Shah answered |
Fossils are generally found in sedimentary rocks.
What was the basic principle of Lamarckism :[CPMT 79, 82]- a)Inheritance of acquired character
- b)Survival of the fittest
- c)Natural selection
- d)Variations
Correct answer is option 'A'. Can you explain this answer?
What was the basic principle of Lamarckism :
[CPMT 79, 82]
a)
Inheritance of acquired character
b)
Survival of the fittest
c)
Natural selection
d)
Variations
|
|
Sadiya Siddique answered |
Lamarckism states that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime.its principle revolves around the fact that the characteristics inherited itself would be passed on. thus, op A.
Largest cranial capacity was found in :
[CPMT 86]
- a)Peking man
- b)Cro-magnon man
- c)Java man
- d)Neanderthal man
Correct answer is option 'D'. Can you explain this answer?
Largest cranial capacity was found in :
[CPMT 86]
a)
Peking man
b)
Cro-magnon man
c)
Java man
d)
Neanderthal man
|
Ritu Singh answered |
Largest cranial capacity was found in Neanderthal man.Cranial capacity of Peking man was 1000 cc to 1300 cc while that of Neanderthal man was 1350 to 1700 cm3. Java man and Cromagnon man had the cranial capacity of 900 cm3 and 1600 cm3 respectively.
Scientific name of man is :[CPMT 71, BHU 78]- a)Canis familiaris
- b)Homo habilis
- c)Homo erectus
- d)Homo sapiens
Correct answer is option 'D'. Can you explain this answer?
Scientific name of man is :
[CPMT 71, BHU 78]
a)
Canis familiaris
b)
Homo habilis
c)
Homo erectus
d)
Homo sapiens
|
Sathvika Tadri answered |
Scientific name of man is Homo sapiens
Tendrils in plants are an example of
- a)Adaptive radiation
- b)Convergent evolution
- c)Divergent evolution
- d)Co-evolution
Correct answer is option 'C'. Can you explain this answer?
Tendrils in plants are an example of
a)
Adaptive radiation
b)
Convergent evolution
c)
Divergent evolution
d)
Co-evolution
|
Ayush Singh answered |
Yes answer should be convergent because no thorns were asked in ques tendrils are many types originating from leaf,stem,stipule which are different in origin
Which of the following orgn in man is not vestigial[CPMT 801]- a)Vermiform appendix
- b)Nictitating membrane
- c)Ear muscles
- d)Epiglottis
Correct answer is option 'D'. Can you explain this answer?
Which of the following orgn in man is not vestigial
[CPMT 801]
a)
Vermiform appendix
b)
Nictitating membrane
c)
Ear muscles
d)
Epiglottis
|
Gowshik.g answered |
Epiglottis.it prevents the entry of food in larynx.
Mutation can be artificially induced by : - a) Radiations
- b)Chemicals
- c)None of them
- d)Both of them
Correct answer is option 'D'. Can you explain this answer?
Mutation can be artificially induced by :
a)
Radiations
b)
Chemicals
c)
None of them
d)
Both of them
|
|
Sadiya Siddique answered |
Mutations can be induced by radiations such as ultraviolet light and by chemical carcinogens (e.g., aflatoxin B1). thus, op D.
Which of the following has homologous organs :[NCERT 78]- a)Hands of man, monkey and kangaroo and trunk of elephant
- b)Wings of insects, birds and bats
- c)Hindi limbs of grasshopper,horse and bat
- d)Mouthparts of cockroach, mosquito and honey bee
Correct answer is option 'D'. Can you explain this answer?
Which of the following has homologous organs :
[NCERT 78]
a)
Hands of man, monkey and kangaroo and trunk of elephant
b)
Wings of insects, birds and bats
c)
Hindi limbs of grasshopper,horse and bat
d)
Mouthparts of cockroach, mosquito and honey bee
|
Preeti Iyer answered |
The insects the mouth parts comprise labrum,mandibles and maxilla (representing similar origin and structure) but they have different functions.
Function of mouth in-
Cockroaches - biting and chewing
Honey bee - chewing and lapping
Mosquito - piercing and sucking.
Evidently,the same structure is developed along different divergent evolution and these structures are Homologous.
Function of mouth in-
Cockroaches - biting and chewing
Honey bee - chewing and lapping
Mosquito - piercing and sucking.
Evidently,the same structure is developed along different divergent evolution and these structures are Homologous.
Evolution is- a)Progressive development of race
- b)History of race
- c)History and development of a race along with variations
- d)Development of race
Correct answer is 'C'. Can you explain this answer?
Evolution is
a)
Progressive development of race
b)
History of race
c)
History and development of a race along with variations
d)
Development of race
|
|
Pooja Mehta answered |
The term evolution was coined by Herbert Spencer, an English philosopher which means unrolling or unfolding of nature that brings about an orderly change from one form or condition to another resulting in descendants becoming different from ancestors. Thus, it is history and development of race along with variations.
The probable first prehistoric man was: [CPMT 79] - a)Ramapithecus
- b)Homo habilis
- c)Australopithecus
- d)Zinjanthropus
Correct answer is option 'B'. Can you explain this answer?
The probable first prehistoric man was:
[CPMT 79]
a)
Ramapithecus
b)
Homo habilis
c)
Australopithecus
d)
Zinjanthropus
|
Pankaj Kulkarni answered |
Homo habilis is a proposed archaic (early) species of Homo which lived between roughly 2.1 and 1.5 million years ago, during the Gelasian (earliest period) and early Calabrian (geologic time scale) stages of the Pleistocene geological epoch (this period lasted from about 2,580,000 to 11,700 years ago).
One major criticism of Darwin's theory is that : [CPMT 82, 83]- a)It presumes that environment upon earth has been changing through ages
- b)It does not explain variations with heredity
- c)It overestimates reproductive capacity of animals and plants
- d)It does not explain vestigial organs
Correct answer is option 'B'. Can you explain this answer?
One major criticism of Darwin's theory is that :
[CPMT 82, 83]
a)
It presumes that environment upon earth has been changing through ages
b)
It does not explain variations with heredity
c)
It overestimates reproductive capacity of animals and plants
d)
It does not explain vestigial organs
|
|
Geetika Shah answered |
Darwinism is an evolutionary theory proposed by Charles Robert Darwin, an English Naturalist. He believed that evolution is a gradual, rather than a sudden biological event. His theory was based on several facts, observations and inferences. They are 1) overproduction, 2) constancy in population, 3) struggle for existence, 4) natural selection.
The prodigality of production or overproduction: Every organism tends to increase its population in large proportions. For example, Paramecium divides by binary fission at the rate of three to four times a day. At this rate, the volume of all the paramecia equals to 10,000 times that of the earth at the end of the 9000th generation in the absence of any check.
Constancy in population: However, such an abnormal increase is not noticed in the population of any species in nature as the offspring die in large number before reaching the reproductive age. It is true that the food and the other sources do not increase in the same proportion as that of the population.
The prodigality of production or overproduction: Every organism tends to increase its population in large proportions. For example, Paramecium divides by binary fission at the rate of three to four times a day. At this rate, the volume of all the paramecia equals to 10,000 times that of the earth at the end of the 9000th generation in the absence of any check.
Constancy in population: However, such an abnormal increase is not noticed in the population of any species in nature as the offspring die in large number before reaching the reproductive age. It is true that the food and the other sources do not increase in the same proportion as that of the population.
Struggle for existence: As the food sources are limited, severe competition exists among the members of a population. Darwin called it a struggle for existence.
Natural selection: The organisms with less reproductive success are not represented in future generations, however, fit they may be in the struggle for existence. This is called the Natural selection. Herbert Spencer called this phenomenon Survival of the fittest.
Darwinism failed to explain the mechanism by which variations occur. Thus Darwin faced the criticism "DARWINISM EXPLAINS THE SURVIVAL OF THE FITTEST BUT NOT THE ARRIVAL OF THE FITTEST".
So, the correct option is 'It does not explain variations with heredity'
If a particular animal hs shelled eggs, hair and teats of the bodyand has cloaca, it may be a connecting link between- a)Reptiles and birds
- b)Birds and mammals
- c)Reptiles and mammals
- d)None of them
Correct answer is option 'C'. Can you explain this answer?
If a particular animal hs shelled eggs, hair and teats of the bodyand has cloaca, it may be a connecting link between
a)
Reptiles and birds
b)
Birds and mammals
c)
Reptiles and mammals
d)
None of them
|
|
Suresh Iyer answered |
Lycaenops was a mammal-like reptile. It is considered a missing link between reptiles and mammals. Laying shelled eggs is a characteristic of birds and reptiles. Having hair, teats on body and cloaca are characteristics of animals. So, particular animal has shelled eggs, hair and teats on the body and has cloaca, it may be a connecting link between reptiles and mammals. Thus, option C is correct and other options are wrong.
Which bird can not fly:[NCERT 77]- a)Stark
- b)penguins
- c)Duck
- d)Peacock
Correct answer is option 'B'. Can you explain this answer?
Which bird can not fly:
[NCERT 77]
a)
Stark
b)
penguins
c)
Duck
d)
Peacock
|
|
Palak Basu answered |
Penguins are birds that cannot fly, but are excellent swimmers, which is why they spend a lot of time in the water. Out of 18 penguin species, only 3 species live exclusively in Antarctica, while the rest are scattered in many places around the Southern Hemisphere
Darwin judged the fitness of an individual by- a)Dominance over other individual
- b)Strategy to obtain food
- c)Ability to defend itself
- d)Number of offspring
Correct answer is option 'D'. Can you explain this answer?
Darwin judged the fitness of an individual by
a)
Dominance over other individual
b)
Strategy to obtain food
c)
Ability to defend itself
d)
Number of offspring
|
|
Rajeev Saxena answered |
Darwin realised that under the intense competition of members in a population, any variation which favoured survival in a particular environment would increase the individuals ability to reproduce and leave fertile offsprings. While less favourable variations decrease the chance of successful reproduction. Hence, Darwin judged the fitness of an individual by reproducing ability and the number of offsprings.
In the population of a species chances of the spreading of a mutant gene increases when it is :[CPMT 78]- a)Recessive
- b)Natural selection occurs
- c)Dominant
- d)Neither dominant recessive
Correct answer is option 'B'. Can you explain this answer?
In the population of a species chances of the spreading of a mutant gene increases when it is :
[CPMT 78]
a)
Recessive
b)
Natural selection occurs
c)
Dominant
d)
Neither dominant recessive
|
Isha Mishra answered |
Natural Selection and Mutant Genes in Population
Natural selection is a process in which organisms that are better adapted to their environment tend to survive and produce more offspring. Mutant genes are new genetic variations that arise in a population due to genetic mutations. In the population of a species, chances of the spreading of a mutant gene increases when natural selection occurs.
Explanation:
- Recessive and Dominant Gene:
Recessive and dominant genes are terms used to describe the inheritance patterns of specific traits. A recessive gene is one that is only expressed when an individual has two copies of that gene. A dominant gene is one that is always expressed when an individual has at least one copy of the gene.
- Mutant Gene:
A mutant gene is a new genetic variation that arises in a population due to genetic mutations. Mutations are changes in the DNA sequence that can result in new traits or variations in existing traits.
- Natural Selection:
Natural selection is the process by which organisms that are better adapted to their environment tend to survive and produce more offspring. This results in the spread of favorable traits throughout the population.
- Chances of Spreading of Mutant Gene:
The chances of the spreading of a mutant gene increases when natural selection occurs. This is because if the mutant gene provides a survival advantage to the organism, then those organisms with the gene will be more likely to survive and reproduce. Over time, this will result in the spread of the mutant gene throughout the population.
- Dominant and Recessive Genes and Mutant Gene:
Dominant and recessive genes do not necessarily affect the chances of the spreading of a mutant gene. Whether a gene is dominant or recessive only determines how the trait is expressed in an individual. The effects of the mutant gene on the survival and reproduction of the organism are what determines whether it will spread throughout the population.
Conclusion:
In conclusion, the chances of the spreading of a mutant gene in the population of a species increases when natural selection occurs. The inheritance pattern of the gene, whether it is dominant or recessive, does not necessarily affect its spread. It is the effects of the gene on the survival and reproduction of the organism that determine its spread throughout the population.
Natural selection is a process in which organisms that are better adapted to their environment tend to survive and produce more offspring. Mutant genes are new genetic variations that arise in a population due to genetic mutations. In the population of a species, chances of the spreading of a mutant gene increases when natural selection occurs.
Explanation:
- Recessive and Dominant Gene:
Recessive and dominant genes are terms used to describe the inheritance patterns of specific traits. A recessive gene is one that is only expressed when an individual has two copies of that gene. A dominant gene is one that is always expressed when an individual has at least one copy of the gene.
- Mutant Gene:
A mutant gene is a new genetic variation that arises in a population due to genetic mutations. Mutations are changes in the DNA sequence that can result in new traits or variations in existing traits.
- Natural Selection:
Natural selection is the process by which organisms that are better adapted to their environment tend to survive and produce more offspring. This results in the spread of favorable traits throughout the population.
- Chances of Spreading of Mutant Gene:
The chances of the spreading of a mutant gene increases when natural selection occurs. This is because if the mutant gene provides a survival advantage to the organism, then those organisms with the gene will be more likely to survive and reproduce. Over time, this will result in the spread of the mutant gene throughout the population.
- Dominant and Recessive Genes and Mutant Gene:
Dominant and recessive genes do not necessarily affect the chances of the spreading of a mutant gene. Whether a gene is dominant or recessive only determines how the trait is expressed in an individual. The effects of the mutant gene on the survival and reproduction of the organism are what determines whether it will spread throughout the population.
Conclusion:
In conclusion, the chances of the spreading of a mutant gene in the population of a species increases when natural selection occurs. The inheritance pattern of the gene, whether it is dominant or recessive, does not necessarily affect its spread. It is the effects of the gene on the survival and reproduction of the organism that determine its spread throughout the population.
Life originated in which era : [CPMT 76]
- a)Proterozoic
- b)Mesozoic
- c)Precambrian
- d)Coenozoic
Correct answer is option 'C'. Can you explain this answer?
Life originated in which era : [CPMT 76]
a)
Proterozoic
b)
Mesozoic
c)
Precambrian
d)
Coenozoic
|
Sandy Naaz answered |
The earliest undisputed evidence of life on Earth dates at least from 3.5billion years ago, during the Eoarchean Era, after a geological crust started to solidify following the earlier molten Hadean Eon.
Connecting link between annelida and mollusca : - a)Cuttle fish
- b)Octopus
- c)Neopilina
- d)Nautilus
Correct answer is option 'C'. Can you explain this answer?
Connecting link between annelida and mollusca :
a)
Cuttle fish
b)
Octopus
c)
Neopilina
d)
Nautilus
|
|
Prisha Bajaj answered |
Neopilina is a connecting link between annelids and molluscans. It is the only segmented mollusc. It has a cup shaped shell like that of limpet. Its visceral mass is divided into five segments, each with a pair of shell muscles, gills, auricles, and nephidia.
According to abiogenesis life originates from ______.- a)Pre-exiting life
- b)Extra-terrestrial matter
- c)Non-living matter
- d)Chemicals
Correct answer is 'C'. Can you explain this answer?
According to abiogenesis life originates from ______.
a)
Pre-exiting life
b)
Extra-terrestrial matter
c)
Non-living matter
d)
Chemicals
|
Hansa Sharma answered |
According to abiogenesis theory of origin of life, life originated from non-living matter like gases, inorganic substance and water at particular temperature and pressure.
What is most important for origin of life
[AFMC 78]
- a)Water
- b)Oxygen
- c)Carbon
- d)Nitrogen
Correct answer is option 'C'. Can you explain this answer?
What is most important for origin of life
[AFMC 78]
a)
Water
b)
Oxygen
c)
Carbon
d)
Nitrogen
|
|
preeti answered |
All the life in evolution when originate origin in water so water is the most essential condition for origin of life.All life forms were in water environment only.
It is believed that the first organisms which inhabitated earth's surface were
[MP PMT 01]
- a)Autotrophs
- b)Mixotrophs
- c)Bacteria
- d)Chromatotrophs
Correct answer is option 'C'. Can you explain this answer?
It is believed that the first organisms which inhabitated earth's surface were
[MP PMT 01]
a)
Autotrophs
b)
Mixotrophs
c)
Bacteria
d)
Chromatotrophs
|
|
Srishti Shah answered |
The first organisms that inhabited Earth's surface were bacteria. This is supported by several lines of evidence.
Fossil Record:
The oldest fossils found on Earth are of bacteria-like organisms. These fossils date back to 3.5 billion years ago. These bacteria were anaerobic, which means that they did not require oxygen to survive.
Chemical Evidence:
The chemical composition of rocks that are 3.8 billion years old suggests that they were formed by bacteria. These rocks contain isotopes of carbon that are only produced by living organisms.
Evolutionary History:
Bacteria are the most ancient and diverse group of organisms on Earth. They have been evolving for billions of years and have adapted to almost every environment on the planet.
Autotrophs and Mixotrophs:
Autotrophs are organisms that can produce their own food using energy from the sun or from inorganic compounds. Mixotrophs are organisms that can switch between being autotrophic and heterotrophic (consuming other organisms for food). While these types of organisms are important in the history of life on Earth, they did not appear until much later in evolution.
Chromatotrophs:
Chromatotrophs are bacteria that use chemicals as their source of energy. While these types of bacteria are also ancient, they are not believed to be the first organisms on Earth.
In conclusion, the first organisms that inhabited Earth's surface were bacteria. They have been evolving for billions of years and have adapted to almost every environment on the planet.
Fossil Record:
The oldest fossils found on Earth are of bacteria-like organisms. These fossils date back to 3.5 billion years ago. These bacteria were anaerobic, which means that they did not require oxygen to survive.
Chemical Evidence:
The chemical composition of rocks that are 3.8 billion years old suggests that they were formed by bacteria. These rocks contain isotopes of carbon that are only produced by living organisms.
Evolutionary History:
Bacteria are the most ancient and diverse group of organisms on Earth. They have been evolving for billions of years and have adapted to almost every environment on the planet.
Autotrophs and Mixotrophs:
Autotrophs are organisms that can produce their own food using energy from the sun or from inorganic compounds. Mixotrophs are organisms that can switch between being autotrophic and heterotrophic (consuming other organisms for food). While these types of organisms are important in the history of life on Earth, they did not appear until much later in evolution.
Chromatotrophs:
Chromatotrophs are bacteria that use chemicals as their source of energy. While these types of bacteria are also ancient, they are not believed to be the first organisms on Earth.
In conclusion, the first organisms that inhabited Earth's surface were bacteria. They have been evolving for billions of years and have adapted to almost every environment on the planet.
Gene pool is[CPMT 88]- a)Genotype of an individual of a population
- b)Different genes of all individuals of a species found in an area
- c)Pool of artificially synthesized genes
- d)Genes of a genus
Correct answer is option 'B'. Can you explain this answer?
Gene pool is
[CPMT 88]
a)
Genotype of an individual of a population
b)
Different genes of all individuals of a species found in an area
c)
Pool of artificially synthesized genes
d)
Genes of a genus
|
|
Just Your answered |
A gene pool is the collection of different genes within an interbreeding population. The concept of a gene pool usually refers to the sum of all the alleles at all of the loci within the genes of a population of a single species.
Which scientist gave the 'Theory of Continuity of Germplasm' : [BHU 82]- a)Weismann
- b)Mendel
- c)Lamarck
- d)Darwin
Correct answer is option 'A'. Can you explain this answer?
Which scientist gave the 'Theory of Continuity of Germplasm' :
[BHU 82]
a)
Weismann
b)
Mendel
c)
Lamarck
d)
Darwin
|
Ahmed Hafeez answered |
This theory was propounded by the scientist named weismann. So the correct choice is A. According to this theory our body is composed of two different types of cells: somatic cells and germ cells and a change in a germ cell gets inherited in next generation.
If population of a species is transfered to more suitable environment then it will show[NCERT 72]- a)More individuals would survive
- b)Protection against enemies
- c)Rate of reproduction increases
- d)Unlimitied food would be available
Correct answer is option 'B'. Can you explain this answer?
If population of a species is transfered to more suitable environment then it will show
[NCERT 72]
a)
More individuals would survive
b)
Protection against enemies
c)
Rate of reproduction increases
d)
Unlimitied food would be available
|
Lalit Yadav answered |
If the population of a species is transferred to the more suitable environment, then it will show protection against enemies. Populations are groups of individuals belonging to the same species that live in the same region at the same time. Population density is a measure of the number of organisms that make up a population in a defined area. In the suitable environment, the species of the population becomes more strong to fight with enemies and protect themselves.
So, the correct answer is option B.
Which charcter applies to Homo sapiens : [CPMT 81]- a)Opposable toe
- b)Large canine
- c)Cranial capacity 1450 cc
- d)Chin prominence absent
Correct answer is option 'C'. Can you explain this answer?
Which charcter applies to Homo sapiens :
[CPMT 81]
a)
Opposable toe
b)
Large canine
c)
Cranial capacity 1450 cc
d)
Chin prominence absent
|
Akhil George answered |
Homo sapiens ( meaning wise human)is considered to have a cranial capacity of 1350-1500cc. Cranial capacity is defined as the cubic capacity of the brain measured in the living by formula based on head measurements and for the skull by filling it with particulate material and measuring the volume of the latter.
Greatest advantage of bipeadal movement :[NCERT 71]- a)Fore arms becoming free for carrying out order of brain
- b)Greater speed
- c)Supports the body properly
- d)Loss of weight
Correct answer is option 'A'. Can you explain this answer?
Greatest advantage of bipeadal movement :
[NCERT 71]
a)
Fore arms becoming free for carrying out order of brain
b)
Greater speed
c)
Supports the body properly
d)
Loss of weight
|
|
Hitakshi Tamta answered |
Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. The greatest advantage of bipedal movement is forearms becoming free for carrying out order of brain. It also raises the head, this allows a greater field of vision with improved detection of distant dangers or resources, access to deeper water for wading animals and allows the animals to reach higher food sources with their mouths. So, the correct answer is option A.
Dinosaurs are : [BHU 83]- a)Primitive amphinians
- b)Extinct reptiles
- c)Giant mammals
- d) Primitive mammals
Correct answer is option 'B'. Can you explain this answer?
Dinosaurs are :
[BHU 83]
a)
Primitive amphinians
b)
Extinct reptiles
c)
Giant mammals
d)
Primitive mammals
|
|
Kaneez Fatima answered |
Dinosaurs went extinct about 65 million years ago (at the end of the Cretaceous Period), after living on Earth for about 165 million years.
- a)Geographical evolution
- b)Convergent evolution
- c)Divergent evolution
- d)Adaptive radiation
Correct answer is 'D'. Can you explain this answer?
|
|
Rajat Kapoor answered |
The diversification of an ancestral group into two or more species in different habitats is called divergent evolution. When this involves large number of species to occupy different ritches, this is called adaptive radiation. Adaptive radiation is the process of evolution of different species in a given geographical area starting from a species of animals or plants and literally radiating to other areas of geography (habitats). Darwin's finches represent one of best examples of this phenomenon. Australian marsupials are another example of adaptive radiation.
Which of the following bird will be called most successfully evolved?- a)Lays 5 eggs, 5 hatch and 5 reproduce
- b)Lays 9 eggs, 9 hatch and 3 reproduce
- c)Lays 2 eggs, 2 hatch and 2 reproduce
- d)Lays 10 eggs, 5 hatch and 4 reproduce
Correct answer is option 'A'. Can you explain this answer?
Which of the following bird will be called most successfully evolved?
a)
Lays 5 eggs, 5 hatch and 5 reproduce
b)
Lays 9 eggs, 9 hatch and 3 reproduce
c)
Lays 2 eggs, 2 hatch and 2 reproduce
d)
Lays 10 eggs, 5 hatch and 4 reproduce
|
Rupesh Ganguli answered |
Correct answer is a because according to Darwin the who leaves more Number of reproducing individuals are more successful
Homo sapiens arose in Africa and moved across continents and developed into distinct races during?- a)Ice age between 75000-10,000 years ago
- b)Ice age between 5000-6000 years ago
- c)Stone age between 10,000 years ago
- d)Stone age between 2000-4000 years ago
Correct answer is option 'A'. Can you explain this answer?
Homo sapiens arose in Africa and moved across continents and developed into distinct races during?
a)
Ice age between 75000-10,000 years ago
b)
Ice age between 5000-6000 years ago
c)
Stone age between 10,000 years ago
d)
Stone age between 2000-4000 years ago
|
|
Kushagra Budhgaya answered |
Answer A is correct. why don't you go through the ncert once.
The weakest point of Darwinism wa that it had no explanation for :[NCERT 71]- a)Struggle for existence
- b)Survival of the fittest
- c)Variations
- d)Enormous rate of production
Correct answer is option 'C'. Can you explain this answer?
The weakest point of Darwinism wa that it had no explanation for :
[NCERT 71]
a)
Struggle for existence
b)
Survival of the fittest
c)
Variations
d)
Enormous rate of production
|
Manju Singh answered |
C) Darwin didn't have the knowledge of genetics and he couldn't tell about variations.
Mutations are generally :[CPMT 85]- a)Recessive
- b)Useful
- c)Harmful
- d)Dominant
Correct answer is option 'A'. Can you explain this answer?
Mutations are generally :
[CPMT 85]
a)
Recessive
b)
Useful
c)
Harmful
d)
Dominant
|
Neha Ghosh Roy answered |
There are two main reasons. 1st,there are introns and exons existed in eukaryotes. Introns do not contain the genetic information but are in large amount in chromosome . So, if the mutation occurs in the introns, it will be recessive.
second, one amino acid will corresponding to several base sequences. For example UUU and UUC all represent phe.This is called degeneracy. so, if the mutation did not change the amino acid, it is also recessive.
Which of the following organs in man is vestigial : [CPMT 77]- a)Pinna
- b)Wisdom tooth
- c)Fossa ovalis
- d)Ileum
Correct answer is option 'B'. Can you explain this answer?
Which of the following organs in man is vestigial : [CPMT 77]
a)
Pinna
b)
Wisdom tooth
c)
Fossa ovalis
d)
Ileum
|
Surya answered |
Vestigial organs means evidence for the evolution.. so as per the given option...wisdom teeth is the vestigial organ...so the option B is correct...
Dinosaurs originated : [CPMT 86]- a)After evolution of mammals
- b)With mammals
- c)Much before mammals
- d)Before mammals and they formed them
Correct answer is option 'B'. Can you explain this answer?
Dinosaurs originated : [CPMT 86]
a)
After evolution of mammals
b)
With mammals
c)
Much before mammals
d)
Before mammals and they formed them
|
|
Siddiq Zayeda answered |
Mammals appeared on the earth long before the extinction of the dinosaurs; in fact, dinosaurs and mammals originated within 10 million years of each other, in the late Triassic about 200 million years ago.........
Fossils are most commonly preserved in______.- a)Sedimentary rocks
- b)Igneous rocks
- c)Metamorphic rocks
- d)Any type of rock
Correct answer is option 'A'. Can you explain this answer?
Fossils are most commonly preserved in______.
a)
Sedimentary rocks
b)
Igneous rocks
c)
Metamorphic rocks
d)
Any type of rock
|
Prerana M N answered |
Sedimentary rocks are mostly involved in forming fossils, owing to the way in which they are formed.
Homologous organs have :[MP PMT 01]- a)Similar origin and similar or dissimilar functions
- b)Dissimilar origin and structure
- c)Dissimilar origin and function
- d)Dissimilar origin and similar functions
Correct answer is option 'A'. Can you explain this answer?
Homologous organs have :
[MP PMT 01]
a)
Similar origin and similar or dissimilar functions
b)
Dissimilar origin and structure
c)
Dissimilar origin and function
d)
Dissimilar origin and similar functions
|
|
Afifa Aaliya answered |
Organs such as bats of wings, wings of birds, seals of flippers, arms of humans have common underlying anatomy. That was present in last common Ancestors. forelimbs are homologous organs. homology refers to the traits inherited by two different organisms from common ancestry. so it has similar origin and different or similar functions.
So option " A " is correct answer.
So option " A " is correct answer.
An inter-breeding population of finches became separated geographically, forming two isolated groups. Each group then became subject to different selective pressures. One group was then introduced into the habitat of the other. Which one of the following would determine whether they now formed two distinct species?- a)They had been separated for more than three million years
- b)They failed to produce fertile F1 hybrids
- c)They showed marked differences in the shape of their beaks
- d)Their plumage had become markedly different
Correct answer is option 'B'. Can you explain this answer?
An inter-breeding population of finches became separated geographically, forming two isolated groups. Each group then became subject to different selective pressures. One group was then introduced into the habitat of the other. Which one of the following would determine whether they now formed two distinct species?
a)
They had been separated for more than three million years
b)
They failed to produce fertile F1 hybrids
c)
They showed marked differences in the shape of their beaks
d)
Their plumage had become markedly different
|
Mira Joshi answered |
Once inter-breeding population of finches, now have failed to produce fertile F1 hybrids, this means they have now formed two distinct species.
Darwin explained origin of species through : [NCERT 75]- a)Hybridization
- b)Mutation
- c)Acquired characters
- d)Natural selection
Correct answer is option 'D'. Can you explain this answer?
Darwin explained origin of species through :
[NCERT 75]
a)
Hybridization
b)
Mutation
c)
Acquired characters
d)
Natural selection
|
|
Vishal Kumar answered |
Darwin’s theory of natural selection states that nature selects organisms that have features favorable for their survival, while eliminating inferior species. Natural selection is a key to the origin of new species from the existing ones. The following article provides information about this theory.
Which of the following is responsible for evolution according to Neo-Darwinism : [CPMT 86]- a)Mutation
- b)Natural selection
- c)Mutation and Natural
- d)Either (1) or (2)
Correct answer is option 'C'. Can you explain this answer?
Which of the following is responsible for evolution according to Neo-Darwinism :
[CPMT 86]
a)
Mutation
b)
Natural selection
c)
Mutation and Natural
d)
Either (1) or (2)
|
|
Raza Great answered |
Natural selection is the core creative agent in evolution, mutations, variations, are also factors leading to the development of new species. Organisms more suited to the environmental conditions will survive empowering the forces of competition. The organism with beneficial mutations, stronger genotype will be the fittest and will survive. After successive generations, all the stronger gene pool leads to an evolution of new species
Who called humans as Homo sapiens wiseman?- a)Carolus Linnaeus
- b)Hugo de Vries
- c)Joseph Walter
- d)Charles Darwin
Correct answer is option 'A'. Can you explain this answer?
Who called humans as Homo sapiens wiseman?
a)
Carolus Linnaeus
b)
Hugo de Vries
c)
Joseph Walter
d)
Charles Darwin
|
|
Priya Menon answered |
The first scientific name of man was given by Carolus Linnaeus. He called them Homo sapiens wiseman. He added wiseman to the name as it was the only organism with high brain capacity.
Ancestor of man who first time showed bipedal movement [CPMT 80]- a)Cro-magnon
- b)Australopithecus
- c)Java apeman
- d)Peking man
Correct answer is option 'B'. Can you explain this answer?
Ancestor of man who first time showed bipedal movement
[CPMT 80]
a)
Cro-magnon
b)
Australopithecus
c)
Java apeman
d)
Peking man
|
Debolina Chopra answered |
Bipedal Movement in Human Ancestors: Australopithecus
Bipedalism, or the ability to walk upright on two legs, is one of the key characteristics that distinguish humans from other primates. The first evidence of bipedal movement in our human ancestors can be traced back to the Australopithecus genus. Australopithecus is a group of extinct hominins that lived in Africa between approximately 4.2 and 1.9 million years ago.
1. Cro-Magnon
Cro-Magnon refers to a group of early modern humans (Homo sapiens) who lived in Europe between approximately 40,000 and 10,000 years ago. They were not the first to exhibit bipedal movement, as bipedalism had already evolved much earlier in our evolutionary history.
2. Australopithecus
Australopithecus is the correct answer to the question. This genus includes several species, such as Australopithecus afarensis and Australopithecus africanus, which lived between 4.2 and 2 million years ago. These early hominins had a unique combination of ape-like and human-like features, including adaptations for bipedal locomotion.
3. Java Man
Java Man, also known as Homo erectus, is an extinct species of hominin that lived in Java, Indonesia, approximately 1.8 million years ago. While Homo erectus is an important species in human evolution, it is not the ancestor who first showed bipedal movement.
4. Peking Man
Peking Man, also known as Homo erectus pekinensis, is an extinct hominin species that lived in China approximately 700,000 to 200,000 years ago. Similar to Java Man, Peking Man is not the ancestor who first exhibited bipedal movement.
Conclusion
The correct answer to the question is Australopithecus. This genus of early hominins, which lived between 4.2 and 2 million years ago, was the first to exhibit bipedal movement. The bipedal adaptations seen in Australopithecus species laid the foundation for the evolution of modern humans and our unique ability to walk upright.
Bipedalism, or the ability to walk upright on two legs, is one of the key characteristics that distinguish humans from other primates. The first evidence of bipedal movement in our human ancestors can be traced back to the Australopithecus genus. Australopithecus is a group of extinct hominins that lived in Africa between approximately 4.2 and 1.9 million years ago.
1. Cro-Magnon
Cro-Magnon refers to a group of early modern humans (Homo sapiens) who lived in Europe between approximately 40,000 and 10,000 years ago. They were not the first to exhibit bipedal movement, as bipedalism had already evolved much earlier in our evolutionary history.
2. Australopithecus
Australopithecus is the correct answer to the question. This genus includes several species, such as Australopithecus afarensis and Australopithecus africanus, which lived between 4.2 and 2 million years ago. These early hominins had a unique combination of ape-like and human-like features, including adaptations for bipedal locomotion.
3. Java Man
Java Man, also known as Homo erectus, is an extinct species of hominin that lived in Java, Indonesia, approximately 1.8 million years ago. While Homo erectus is an important species in human evolution, it is not the ancestor who first showed bipedal movement.
4. Peking Man
Peking Man, also known as Homo erectus pekinensis, is an extinct hominin species that lived in China approximately 700,000 to 200,000 years ago. Similar to Java Man, Peking Man is not the ancestor who first exhibited bipedal movement.
Conclusion
The correct answer to the question is Australopithecus. This genus of early hominins, which lived between 4.2 and 2 million years ago, was the first to exhibit bipedal movement. The bipedal adaptations seen in Australopithecus species laid the foundation for the evolution of modern humans and our unique ability to walk upright.
There are no life in which era :[CPMT 80]- a)Messozoic era
- b)Palaeozoic era
- c)Coenozoic era
- d)Azoic era
Correct answer is option 'D'. Can you explain this answer?
There are no life in which era :
[CPMT 80]
a)
Messozoic era
b)
Palaeozoic era
c)
Coenozoic era
d)
Azoic era
|
|
Ayeshashreya Mishra answered |
During Azoic era, the earth was with out plants and animals. The rock layers which were formed soon after azoic era contains the remains of limy sea plants.The word "Azoic" is derived from the Greek, a- meaning without and zoon meaning animal (or living being), it was first used to mean without life.....
An era ''age of birds and mammals'' is : [CPMT 93]- a)Mesozoic
- b)Palaecozoic
- c)Coenozoic
- d)Cretaceous
Correct answer is option 'C'. Can you explain this answer?
An era ''age of birds and mammals'' is : [CPMT 93]
a)
Mesozoic
b)
Palaecozoic
c)
Coenozoic
d)
Cretaceous
|
|
Afifa Aaliya answered |
The Cenozoic era is the most recent of the three major sub division of the animal history. The other two are the Mesozoic and Peliozoic eras. The Cenozoic era only about 65 million years. From the end of the Cretaceous period and the extension of non avian dinosaurs to the present. The Cenozoic is sometimes called as age of mammals because the largest land animals have been mammals during that time.
So option " C " is correct answer.
So option " C " is correct answer.
Mortality in babies is an example of ______- a)Stabilizing selection
- b)Directional selection
- c)Disruptive selection
- d)Abortion selection
Correct answer is option 'A'. Can you explain this answer?
Mortality in babies is an example of ______
a)
Stabilizing selection
b)
Directional selection
c)
Disruptive selection
d)
Abortion selection
|
|
Dhruba Mukherjee answered |
Mortality in babies is an example of Stabilizing selection.
Stabilizing Selection:
Stabilizing selection, also known as normalizing selection or purifying selection, is a type of natural selection that favors the average individuals in a population while selecting against extreme phenotypes. This type of selection reduces genetic diversity and maintains the status quo, resulting in a stable population over time.
Explanation:
In the case of mortality in babies, stabilizing selection is at play. Stabilizing selection occurs when the average individuals in a population have a higher fitness compared to individuals with extreme phenotypes. In this context, babies with average characteristics have a higher chance of survival compared to those with extreme characteristics.
Factors that contribute to baby mortality can include genetic abnormalities, birth defects, premature birth, low birth weight, maternal health issues, and environmental factors. Babies with extreme phenotypes, such as severe genetic abnormalities or extremely low birth weight, may have a lower chance of survival due to the increased risks associated with these conditions.
By favoring babies with average characteristics, stabilizing selection helps to maintain a stable population over time. This is because extreme phenotypes are more likely to be less fit and less likely to survive to reproductive age, reducing their contribution to future generations.
Stabilizing selection in the context of baby mortality helps to ensure that the average characteristics of the population are maintained and that genetic diversity is not significantly reduced. It acts as a natural mechanism to maintain the health and stability of the population by selecting against extreme phenotypes that may have a higher risk of mortality.
In conclusion, mortality in babies is an example of stabilizing selection because it favors average individuals in a population while selecting against extreme phenotypes, helping to maintain a stable population over time.
Stabilizing Selection:
Stabilizing selection, also known as normalizing selection or purifying selection, is a type of natural selection that favors the average individuals in a population while selecting against extreme phenotypes. This type of selection reduces genetic diversity and maintains the status quo, resulting in a stable population over time.
Explanation:
In the case of mortality in babies, stabilizing selection is at play. Stabilizing selection occurs when the average individuals in a population have a higher fitness compared to individuals with extreme phenotypes. In this context, babies with average characteristics have a higher chance of survival compared to those with extreme characteristics.
Factors that contribute to baby mortality can include genetic abnormalities, birth defects, premature birth, low birth weight, maternal health issues, and environmental factors. Babies with extreme phenotypes, such as severe genetic abnormalities or extremely low birth weight, may have a lower chance of survival due to the increased risks associated with these conditions.
By favoring babies with average characteristics, stabilizing selection helps to maintain a stable population over time. This is because extreme phenotypes are more likely to be less fit and less likely to survive to reproductive age, reducing their contribution to future generations.
Stabilizing selection in the context of baby mortality helps to ensure that the average characteristics of the population are maintained and that genetic diversity is not significantly reduced. It acts as a natural mechanism to maintain the health and stability of the population by selecting against extreme phenotypes that may have a higher risk of mortality.
In conclusion, mortality in babies is an example of stabilizing selection because it favors average individuals in a population while selecting against extreme phenotypes, helping to maintain a stable population over time.
Links between organisms that show branching pattern of evolutionary relationships are shown by- a)Phylogenetic trees
- b)Living fossils
- c)Comparative embryology
- d)Two fossil layers
Correct answer is option 'A'. Can you explain this answer?
Links between organisms that show branching pattern of evolutionary relationships are shown by
a)
Phylogenetic trees
b)
Living fossils
c)
Comparative embryology
d)
Two fossil layers
|
|
Krithika Kumar answered |
Phylogenetic trees are diagrams that show the evolutionary relationships between different organisms. They are used to display the branching pattern of evolutionary relationships between organisms. The diagram looks like a tree with branches that represent different groups of organisms. These branches are called clades, and they represent groups of organisms that have descended from a common ancestor.
Phylogenetic trees are constructed based on a variety of data, including:
1. Morphological characteristics: The physical features of organisms, such as their shape, size, and structure.
2. Molecular data: DNA and RNA sequences are used to compare the genetic makeup of different organisms.
3. Fossil records: The study of fossils provides evidence of the evolutionary history of organisms.
Phylogenetic trees are an important tool for understanding the relationships between organisms and how they have evolved over time. They can be used to answer questions about the origins of different species and how they are related to one another.
In conclusion, phylogenetic trees are diagrams that show the branching pattern of evolutionary relationships between organisms. They are constructed based on a variety of data, including morphological characteristics, molecular data, and fossil records. They are an important tool for understanding the evolutionary history of organisms.
Phylogenetic trees are constructed based on a variety of data, including:
1. Morphological characteristics: The physical features of organisms, such as their shape, size, and structure.
2. Molecular data: DNA and RNA sequences are used to compare the genetic makeup of different organisms.
3. Fossil records: The study of fossils provides evidence of the evolutionary history of organisms.
Phylogenetic trees are an important tool for understanding the relationships between organisms and how they have evolved over time. They can be used to answer questions about the origins of different species and how they are related to one another.
In conclusion, phylogenetic trees are diagrams that show the branching pattern of evolutionary relationships between organisms. They are constructed based on a variety of data, including morphological characteristics, molecular data, and fossil records. They are an important tool for understanding the evolutionary history of organisms.
By studying analogous structures we look for ______.- a)Similarities in appearance but differences in functions
- b)Similarities in appearance and function but different in structure
- c)Similarities in organ structure
- d)Similarities in cell make up
Correct answer is option 'B'. Can you explain this answer?
By studying analogous structures we look for ______.
a)
Similarities in appearance but differences in functions
b)
Similarities in appearance and function but different in structure
c)
Similarities in organ structure
d)
Similarities in cell make up
|
|
Jaideep Chakraborty answered |
Introduction:
Studying analogous structures helps us understand the similarities and differences between organisms that have evolved independently. These structures may have similar functions but different evolutionary origins. By studying these structures, we can gain insights into convergent evolution and the adaptations that organisms have developed to fulfill similar roles in their environments.
Explanation:
Similarities in appearance and function:
Analogous structures refer to structures in different organisms that have similar functions but different evolutionary origins. These structures have evolved independently in response to similar environmental pressures, resulting in similar functions. For example, the wings of birds and bats are analogous structures because they serve the same purpose of enabling flight, but they have evolved from different ancestral structures.
Differences in structure:
While analogous structures may have similar functions, they often have different underlying structures. This is because they have evolved through convergent evolution, where different species independently develop similar traits. For example, the wings of birds are composed of feathers, while the wings of bats are formed by a thin membrane of skin stretched between elongated fingers.
Importance of studying analogous structures:
1. Understanding convergent evolution: By studying analogous structures, we can gain insights into how different organisms have independently evolved similar traits. This helps us understand the process of convergent evolution and how organisms adapt to similar environmental challenges.
2. Determining evolutionary relationships: Analogous structures can sometimes be misleading when trying to determine evolutionary relationships between organisms. For example, dolphins and sharks have similar streamlined body shapes, but they are not closely related. By studying analogous structures in conjunction with other evidence such as genetics, scientists can more accurately determine evolutionary relationships.
3. Identifying adaptive traits: Analogous structures often represent adaptations to similar ecological niches. By studying these structures, we can identify the key traits that enable organisms to thrive in specific environments. This knowledge can be applied to various fields, such as biomimicry, where engineers and designers draw inspiration from nature to create innovative solutions.
Conclusion:
Studying analogous structures allows us to explore the fascinating world of convergent evolution. By comparing the similarities and differences in appearance, function, and structure of these structures, we can gain a deeper understanding of how organisms adapt to their environments and the complex processes of evolution.
Studying analogous structures helps us understand the similarities and differences between organisms that have evolved independently. These structures may have similar functions but different evolutionary origins. By studying these structures, we can gain insights into convergent evolution and the adaptations that organisms have developed to fulfill similar roles in their environments.
Explanation:
Similarities in appearance and function:
Analogous structures refer to structures in different organisms that have similar functions but different evolutionary origins. These structures have evolved independently in response to similar environmental pressures, resulting in similar functions. For example, the wings of birds and bats are analogous structures because they serve the same purpose of enabling flight, but they have evolved from different ancestral structures.
Differences in structure:
While analogous structures may have similar functions, they often have different underlying structures. This is because they have evolved through convergent evolution, where different species independently develop similar traits. For example, the wings of birds are composed of feathers, while the wings of bats are formed by a thin membrane of skin stretched between elongated fingers.
Importance of studying analogous structures:
1. Understanding convergent evolution: By studying analogous structures, we can gain insights into how different organisms have independently evolved similar traits. This helps us understand the process of convergent evolution and how organisms adapt to similar environmental challenges.
2. Determining evolutionary relationships: Analogous structures can sometimes be misleading when trying to determine evolutionary relationships between organisms. For example, dolphins and sharks have similar streamlined body shapes, but they are not closely related. By studying analogous structures in conjunction with other evidence such as genetics, scientists can more accurately determine evolutionary relationships.
3. Identifying adaptive traits: Analogous structures often represent adaptations to similar ecological niches. By studying these structures, we can identify the key traits that enable organisms to thrive in specific environments. This knowledge can be applied to various fields, such as biomimicry, where engineers and designers draw inspiration from nature to create innovative solutions.
Conclusion:
Studying analogous structures allows us to explore the fascinating world of convergent evolution. By comparing the similarities and differences in appearance, function, and structure of these structures, we can gain a deeper understanding of how organisms adapt to their environments and the complex processes of evolution.
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