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All questions of Evidence for Evolution for Year 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.
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Which of the following is the relatively most accurate method for dating of fossils?
[2005]
- a)Electron Spin Resonance method
- b)Potassium-argon method
- c)Radio-carbon method
- d)Uranium-lead method
Correct answer is option 'A'. Can you explain this answer?
Which of the following is the relatively most accurate method for dating of fossils?
[2005]
a)
Electron Spin Resonance method
b)
Potassium-argon method
c)
Radio-carbon method
d)
Uranium-lead method
|
Megha Joshi answered |
Electron Spin Resonance Method for Dating Fossils
The most accurate method for dating fossils is the Electron Spin Resonance (ESR) method. Let's understand the method in detail:
What is Electron Spin Resonance Method?
Electron Spin Resonance (ESR) dating is a method that is used to date materials containing atoms with unpaired electrons, such as organic and inorganic materials, tooth enamel, and fossil bones. This method is based on the fact that electrons become trapped in the mineral's crystalline structure over time due to exposure to natural radiation. The trapped electrons then accumulate over time, and their number can be measured to determine the age of the fossil.
Advantages of ESR Method:
1. Accurate: The ESR method is relatively more accurate than other dating methods.
2. Wide Range of Application: The ESR method can be used to date materials that are millions of years old.
3. Non-destructive: The ESR method is a non-destructive method, which means that the fossil can be preserved after the testing is done.
Limitations of ESR Method:
1. Requires Large Sample: The ESR method requires a relatively large sample size, which may not always be possible in the case of fossils.
2. Limited Availability: The ESR method is not widely available, and only a few laboratories are equipped to perform the testing.
3. Complex Process: The ESR method is a complex process that requires specialized equipment and trained personnel.
Conclusion:
In conclusion, the ESR method is considered the most accurate method for dating fossils. Although it has some limitations, the ESR method provides valuable information about the age of fossils and their evolutionary history.
The most accurate method for dating fossils is the Electron Spin Resonance (ESR) method. Let's understand the method in detail:
What is Electron Spin Resonance Method?
Electron Spin Resonance (ESR) dating is a method that is used to date materials containing atoms with unpaired electrons, such as organic and inorganic materials, tooth enamel, and fossil bones. This method is based on the fact that electrons become trapped in the mineral's crystalline structure over time due to exposure to natural radiation. The trapped electrons then accumulate over time, and their number can be measured to determine the age of the fossil.
Advantages of ESR Method:
1. Accurate: The ESR method is relatively more accurate than other dating methods.
2. Wide Range of Application: The ESR method can be used to date materials that are millions of years old.
3. Non-destructive: The ESR method is a non-destructive method, which means that the fossil can be preserved after the testing is done.
Limitations of ESR Method:
1. Requires Large Sample: The ESR method requires a relatively large sample size, which may not always be possible in the case of fossils.
2. Limited Availability: The ESR method is not widely available, and only a few laboratories are equipped to perform the testing.
3. Complex Process: The ESR method is a complex process that requires specialized equipment and trained personnel.
Conclusion:
In conclusion, the ESR method is considered the most accurate method for dating fossils. Although it has some limitations, the ESR method provides valuable information about the age of fossils and their evolutionary history.
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
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the abiogenic origin of life?
a)They were partially isolated from the surroundingb)They could separate combinations of molecules from the surroundingsc)They could maintain an internal environmentd)They were able to reproduceCorrect answer is option 'B'. Can you explain this answer?
|
Vijay Bansal answered |
The answer is b.
They could maintain an internal environment
Homoeostasis is keeping the internal environment of the body constant. It is necessary for normal life processes. Microspheres are molecular aggregates of proteinoids. Oparin and Sydney Fox held that large organic molecules synthesized abiotically on primitive earth formed large colloidal aggregates due to the intermolecular attraction. These colloidal particles were called coacervates. Oparin called giant nucleoprotein poid molecules as protobionts. These reproduce either by budding a binary fission but do not exhibit homoeostasis.
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the biogenic origin of life?[2008]- a)They were able to reproduce
- b)They could separate combinations of molecules from the surroundings
- c)They were partially isolated from the surroundings
- d)They could maintain an internal environment
Correct answer is option 'B'. Can you explain this answer?
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the biogenic origin of life?
[2008]
a)
They were able to reproduce
b)
They could separate combinations of molecules from the surroundings
c)
They were partially isolated from the surroundings
d)
They could maintain an internal environment
|
Dipanjan Mehta answered |
Coacervate is an aggregate of macromolecules such as proteins, lipids and membrane and contain enzymes that are capable of converting such substance as glucose into more complex molecules, such as starch. Coacervate droplets arise spontaneously under appropriate conditions and may have been the prebiological systems from which living organisms originated.
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.
Hardy-Weinberg operates in the absence of:- a)Mutations
- b)Natural selection
- c)Recombination
- d)All of these
Correct answer is option 'D'. Can you explain this answer?
Hardy-Weinberg operates in the absence of:
a)
Mutations
b)
Natural selection
c)
Recombination
d)
All of these
|
|
Manisha Choudhury answered |
Hardy-Weinberg equilibrium is a mathematical model that describes the relationship between allele frequencies and genotype frequencies in a population. The equilibrium operates under certain assumptions, which include the absence of mutations, natural selection, migration, and genetic drift. However, the equilibrium can be disrupted by any of these factors, leading to changes in allele and genotype frequencies over time.
Explanation:
Assumptions of Hardy-Weinberg equilibrium:
The Hardy-Weinberg equilibrium assumes the following conditions:
1. Large population size: The population is large enough to prevent genetic drift, which is the random fluctuation of allele frequencies due to chance events.
2. Random mating: The individuals in the population mate randomly, without any preference for certain traits or genetic backgrounds.
3. No migration: There is no movement of individuals into or out of the population, which could introduce new alleles or remove existing ones.
4. No mutations: There are no new mutations arising in the population, which could alter the genetic code and create new alleles.
5. No natural selection: There is no differential survival or reproduction of individuals based on their genotype, which could favor certain alleles over others.
Consequences of violating the assumptions:
If any of these assumptions is violated, the equilibrium will be disrupted, and the allele and genotype frequencies will change over time. For instance:
1. Small population size: In a small population, genetic drift can have a significant effect on allele frequencies, leading to the loss or fixation of alleles.
2. Non-random mating: If individuals mate preferentially based on certain traits or genetic backgrounds, it can create non-random associations between alleles and increase the frequency of certain genotypes.
3. Migration: If individuals move into or out of the population, it can introduce new alleles or remove existing ones, altering the genetic makeup of the population.
4. Mutations: If new mutations arise, they can create new alleles or alter existing ones, leading to changes in allele frequencies.
5. Natural selection: If certain genotypes have a higher fitness than others, they will be more likely to survive and reproduce, leading to changes in allele frequencies.
Conclusion:
In summary, the Hardy-Weinberg equilibrium is a useful tool for understanding how allele and genotype frequencies are related in a population, but it operates under certain assumptions that may not always be true in real-world populations. By violating these assumptions, various factors can disrupt the equilibrium and cause changes in the genetic makeup of a population over time.
Explanation:
Assumptions of Hardy-Weinberg equilibrium:
The Hardy-Weinberg equilibrium assumes the following conditions:
1. Large population size: The population is large enough to prevent genetic drift, which is the random fluctuation of allele frequencies due to chance events.
2. Random mating: The individuals in the population mate randomly, without any preference for certain traits or genetic backgrounds.
3. No migration: There is no movement of individuals into or out of the population, which could introduce new alleles or remove existing ones.
4. No mutations: There are no new mutations arising in the population, which could alter the genetic code and create new alleles.
5. No natural selection: There is no differential survival or reproduction of individuals based on their genotype, which could favor certain alleles over others.
Consequences of violating the assumptions:
If any of these assumptions is violated, the equilibrium will be disrupted, and the allele and genotype frequencies will change over time. For instance:
1. Small population size: In a small population, genetic drift can have a significant effect on allele frequencies, leading to the loss or fixation of alleles.
2. Non-random mating: If individuals mate preferentially based on certain traits or genetic backgrounds, it can create non-random associations between alleles and increase the frequency of certain genotypes.
3. Migration: If individuals move into or out of the population, it can introduce new alleles or remove existing ones, altering the genetic makeup of the population.
4. Mutations: If new mutations arise, they can create new alleles or alter existing ones, leading to changes in allele frequencies.
5. Natural selection: If certain genotypes have a higher fitness than others, they will be more likely to survive and reproduce, leading to changes in allele frequencies.
Conclusion:
In summary, the Hardy-Weinberg equilibrium is a useful tool for understanding how allele and genotype frequencies are related in a population, but it operates under certain assumptions that may not always be true in real-world populations. By violating these assumptions, various factors can disrupt the equilibrium and cause changes in the genetic makeup of a population over time.
Industrial melanism is an example of:- a)Drug resistance
- b)Darkening of skin due to smoke from industries
- c)Defensive adaptation of skin against UV-rays
- d)Protective resemblance with the surrounding
Correct answer is 'D'. Can you explain this answer?
Industrial melanism is an example of:
a)
Drug resistance
b)
Darkening of skin due to smoke from industries
c)
Defensive adaptation of skin against UV-rays
d)
Protective resemblance with the surrounding
|
Nikita Singh answered |
- Industrial melanism is an adaptation where the moths living in industrial areas develop melanin pigments to match their body to the soot covered surroundings.
- In this case, moths with dark coloured will be selected by nature and hence they will be reproductively successful as compared to moths of light colour. Hence it is an example of protective colouration.
There is no life on moon due to the absence of[2002]- a)O2
- b)water
- c)light
- d)temperature
Correct answer is option 'B'. Can you explain this answer?
There is no life on moon due to the absence of
[2002]
a)
O2
b)
water
c)
light
d)
temperature
|
|
Naina Dey answered |
Explanation:
The moon is a lifeless celestial body and there are several factors that contribute to the absence of life on the moon. Out of these factors, the absence of water is the most significant reason. Let us discuss this in detail:
1. Absence of Water:
Water is an essential requirement for life to exist. It is a vital component for the survival of most living organisms, including humans. The moon's surface is dry and barren and there is no evidence of liquid water on the moon. Although there is some water on the moon in the form of ice, it is not sufficient to support life.
2. Lack of Atmosphere:
The moon has a very thin and weak atmosphere. It does not have a protective ozone layer like the Earth, which shields us from harmful radiation from the sun. This means that the moon's surface is constantly exposed to harmful radiation and solar winds, making it a hostile environment for life.
3. Extreme Temperatures:
The moon's surface experiences extreme temperatures ranging from -173°C to 127°C. These extreme temperatures make it impossible for any living organism to survive on the moon.
4. Lack of Organic Matter:
Organic matter is a vital component for the existence of life. It is the building block of all living organisms. The moon's surface does not contain any organic matter, which makes it impossible for life to exist.
Conclusion:
In conclusion, the absence of water is the most significant reason why life cannot exist on the moon. The lack of atmosphere, extreme temperatures, and absence of organic matter are also contributing factors.
The moon is a lifeless celestial body and there are several factors that contribute to the absence of life on the moon. Out of these factors, the absence of water is the most significant reason. Let us discuss this in detail:
1. Absence of Water:
Water is an essential requirement for life to exist. It is a vital component for the survival of most living organisms, including humans. The moon's surface is dry and barren and there is no evidence of liquid water on the moon. Although there is some water on the moon in the form of ice, it is not sufficient to support life.
2. Lack of Atmosphere:
The moon has a very thin and weak atmosphere. It does not have a protective ozone layer like the Earth, which shields us from harmful radiation from the sun. This means that the moon's surface is constantly exposed to harmful radiation and solar winds, making it a hostile environment for life.
3. Extreme Temperatures:
The moon's surface experiences extreme temperatures ranging from -173°C to 127°C. These extreme temperatures make it impossible for any living organism to survive on the moon.
4. Lack of Organic Matter:
Organic matter is a vital component for the existence of life. It is the building block of all living organisms. The moon's surface does not contain any organic matter, which makes it impossible for life to exist.
Conclusion:
In conclusion, the absence of water is the most significant reason why life cannot exist on the moon. The lack of atmosphere, extreme temperatures, and absence of organic matter are also contributing factors.
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
Convergent evolution is illustrated by[2003]- a)dogfish and whale
- b)rat and dog
- c)bacterium and protozoan
- d)starfish and cuttle fish
Correct answer is option 'A'. Can you explain this answer?
Convergent evolution is illustrated by
[2003]
a)
dogfish and whale
b)
rat and dog
c)
bacterium and protozoan
d)
starfish and cuttle fish
|
Ritika Khanna answered |
Independent formation of functionally similar structures by unrelated organism is called convergent evolution.
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
|
Aditi Priya answered |
Bcoz epiglottis helps in obstructing the entry of bolous into the trachea
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.
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 one of the following statement is correct?[2007]- a)There is no evidence of the existence of gills during embryogenesis of mammals
- b)All plant and animal cells are totipotent
- c)Ontogeny repeats phylogeny
- d)Stem cells are specialize cells.
Correct answer is option 'C'. Can you explain this answer?
Which one of the following statement is correct?
[2007]
a)
There is no evidence of the existence of gills during embryogenesis of mammals
b)
All plant and animal cells are totipotent
c)
Ontogeny repeats phylogeny
d)
Stem cells are specialize cells.
|
Gowri Nair answered |
Ontogeny repeats phylogeny.
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).
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
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.
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.
Which of the following are homologous organs?[2002]- a)Wings of birds and locust
- b)Wings of birds (sparrow) and pectoral fins of fish
- c)Wings of bat and butterfly
- d)Legs of frog and cockroach
Correct answer is option 'B'. Can you explain this answer?
Which of the following are homologous organs?
[2002]
a)
Wings of birds and locust
b)
Wings of birds (sparrow) and pectoral fins of fish
c)
Wings of bat and butterfly
d)
Legs of frog and cockroach
|
|
Anshu Saha answered |
Homologous organs are those organs, which have the same origin and similar basic structure but may differ in external appearance and function. Wings of birds and pectoral fins of fishes are an example of the homologous organs.
Geographic and reproductive isolations are most closely associated with:- a)Speciation
- b)Succession
- c)Competition
- d)Extinction
Correct answer is option 'A'. Can you explain this answer?
Geographic and reproductive isolations are most closely associated with:
a)
Speciation
b)
Succession
c)
Competition
d)
Extinction
|
|
Sreemoyee Pillai answered |
Geographic and reproductive isolation are two important factors that can lead to speciation, which is the formation of new species. Let's explore each of these isolations in detail:
Geographic isolation:
This type of isolation refers to the physical separation of populations of a species due to some geographic barrier such as a mountain range, river, or ocean. When populations are separated in this way, they are no longer able to interbreed with each other. Over time, genetic differences can accumulate in each population due to natural selection, genetic drift, and mutation. Eventually, these differences can become so great that the two populations can no longer produce viable offspring if they were to come back into contact. This can lead to the formation of two distinct species.
Reproductive isolation:
This type of isolation occurs when two populations of a species are geographically close to each other but cannot interbreed due to some barrier to reproduction. The barriers can be prezygotic or postzygotic. Prezygotic barriers prevent mating or fertilization from occurring, while postzygotic barriers prevent the development of viable offspring. Some examples of prezygotic barriers include different mating behaviors, incompatible genitalia, or different flowering times. Examples of postzygotic barriers include hybrid inviability or hybrid sterility. Over time, the accumulation of genetic differences due to these barriers can also lead to the formation of new species.
In conclusion, geographic and reproductive isolations are both important factors that can lead to speciation, which is the formation of new species. These isolations prevent gene flow between populations, allowing for genetic divergence and the accumulation of differences that can eventually lead to the formation of new species.
Geographic isolation:
This type of isolation refers to the physical separation of populations of a species due to some geographic barrier such as a mountain range, river, or ocean. When populations are separated in this way, they are no longer able to interbreed with each other. Over time, genetic differences can accumulate in each population due to natural selection, genetic drift, and mutation. Eventually, these differences can become so great that the two populations can no longer produce viable offspring if they were to come back into contact. This can lead to the formation of two distinct species.
Reproductive isolation:
This type of isolation occurs when two populations of a species are geographically close to each other but cannot interbreed due to some barrier to reproduction. The barriers can be prezygotic or postzygotic. Prezygotic barriers prevent mating or fertilization from occurring, while postzygotic barriers prevent the development of viable offspring. Some examples of prezygotic barriers include different mating behaviors, incompatible genitalia, or different flowering times. Examples of postzygotic barriers include hybrid inviability or hybrid sterility. Over time, the accumulation of genetic differences due to these barriers can also lead to the formation of new species.
In conclusion, geographic and reproductive isolations are both important factors that can lead to speciation, which is the formation of new species. These isolations prevent gene flow between populations, allowing for genetic divergence and the accumulation of differences that can eventually lead to the formation of new species.
Sequence of which of the followings is used to know the phylogeny?[2002]- a)mRNA
- b)rRNA
- c)tRNA
- d)DNA
Correct answer is option 'B'. Can you explain this answer?
Sequence of which of the followings is used to know the phylogeny?
[2002]
a)
mRNA
b)
rRNA
c)
tRNA
d)
DNA
|
Ruchi Chakraborty answered |
rRNA occurs in side ribosomes and involved in protein synthesis, mRNA brings coded information from DNA to form polypeptides. tRNA takes part in transferring amino acids from cellular pool to episomes for polymerization to form polypeptides.
Carl Woese gave the theory of life based on his discovery that the genes encoding ribosomal RNA are ancient and distributed over all lineages of life with little or no gene transfer. Therefore rRNA are commonly used to infer phylogeny.
Carl Woese gave the theory of life based on his discovery that the genes encoding ribosomal RNA are ancient and distributed over all lineages of life with little or no gene transfer. Therefore rRNA are commonly used to infer phylogeny.
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.
Oxygen in atmosphere has been formed by :- a)Evporation of water
- b)Photosynthesis of plants
- c)Metabolism of microorganisms
- d)Decaying organisms
Correct answer is option 'B'. Can you explain this answer?
Oxygen in atmosphere has been formed by :
a)
Evporation of water
b)
Photosynthesis of plants
c)
Metabolism of microorganisms
d)
Decaying organisms
|
Abdul Saleem4367 answered |
Today phytoplankton and terrestrial green plants maintain a steady balance in the amount of the earth's atmospheric oxygen....a mature forest takes in carbon dioxide from the atmosphere during photosynthesis and converts it to oxygen to support new growth.....
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
What is common between parrot, platypus and kangaroo?[2007]- a)Toothless jaws
- b)Functional post-end tail
- c)Ovoparity
- d)Homeothermy
Correct answer is option 'D'. Can you explain this answer?
What is common between parrot, platypus and kangaroo?
[2007]
a)
Toothless jaws
b)
Functional post-end tail
c)
Ovoparity
d)
Homeothermy
|
Ayush Sengupta answered |
Only birds and mammals are homeothermous.
Evolutionary history of an organism is known as[2006]- a)Ancestry
- b)Paleontology
- c)Ontogeny
- d)Phylogeny
Correct answer is option 'D'. Can you explain this answer?
Evolutionary history of an organism is known as
[2006]
a)
Ancestry
b)
Paleontology
c)
Ontogeny
d)
Phylogeny
|
Mahi Shah answered |
Paleontolog y is the study of fossils. Ontogeny is the process of development of organism in the embryo stage and phylogeny is known as the history of an organism through ages during evolution.
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.
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.
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...
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.
Thorn of Bougainvillea and tendril of cucurbita are example of[2008]- a)analogous organs
- b)homologous organs
- c)vestigial organs
- d)retrogressive evolution
Correct answer is option 'B'. Can you explain this answer?
Thorn of Bougainvillea and tendril of cucurbita are example of
[2008]
a)
analogous organs
b)
homologous organs
c)
vestigial organs
d)
retrogressive evolution
|
Devansh Mehra answered |
Thorn of Bougainvillea and tendril of Cucurbita are example of homologous chromosomes.
Age of fossils in the past was generally determined by radio-carbon method and other methods involving radioactive elements found in the rocks. More precise methods, which were used recently and led to the revision of the evolutionary periods for different groups of organisms, includes[2004]- a)study of carbohydrates / proteins in fossils
- b)study of the conditions of fossilization
- c)electron spin resonance (ESR) and fossil DNA
- d)study of carbohydrates / proteins in rocks
Correct answer is option 'C'. Can you explain this answer?
Age of fossils in the past was generally determined by radio-carbon method and other methods involving radioactive elements found in the rocks. More precise methods, which were used recently and led to the revision of the evolutionary periods for different groups of organisms, includes
[2004]
a)
study of carbohydrates / proteins in fossils
b)
study of the conditions of fossilization
c)
electron spin resonance (ESR) and fossil DNA
d)
study of carbohydrates / proteins in rocks
|
|
Ruchi Chakraborty answered |
ESR, Electron Spin Resonance measures number of charges occupying deep traps in crystal band gap.
Electron Paramagnetic Resonance (EPR) or Electron Spin Resonance (ESR) is a spectroscopic technique which detects species that have unpaired electrons, generally meaning that the molecule in question is a free radical if it is an organic molecule, or that it has transition metal ions if it is an inorganic complex. Because most stable molecules have a closed-shell configuration without a suitable unpaired spin, the technique is less widely used than nuclear magnetic resonance (NMR). The EPR was first discovered in Kazan State University by Soviet physicist Yevgeniy Zavoyskiy in 1944
Electron Paramagnetic Resonance (EPR) or Electron Spin Resonance (ESR) is a spectroscopic technique which detects species that have unpaired electrons, generally meaning that the molecule in question is a free radical if it is an organic molecule, or that it has transition metal ions if it is an inorganic complex. Because most stable molecules have a closed-shell configuration without a suitable unpaired spin, the technique is less widely used than nuclear magnetic resonance (NMR). The EPR was first discovered in Kazan State University by Soviet physicist Yevgeniy Zavoyskiy in 1944
- 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.
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.........
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.
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.
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.
Animals have the innate ability to escape from predation. Examples for the same are given below. Select the incorrect example.[2005]- a)Colour change in Chameleon
- b)Enlargement of body size by swallowing air in puffer fish
- c)Poison fangs in snakes
- d)Melanism in moths
Correct answer is option 'C'. Can you explain this answer?
Animals have the innate ability to escape from predation. Examples for the same are given below. Select the incorrect example.
[2005]
a)
Colour change in Chameleon
b)
Enlargement of body size by swallowing air in puffer fish
c)
Poison fangs in snakes
d)
Melanism in moths
|
|
Ritika Khanna answered |
Animals resist predation by cryptic coloration deceptive marking, behavioural defenses and possession of mechanical or chemical defenses. Examples are colour change in Chameleon Enlargement of body size by swallowing air in potter fish, Melanism in moths.
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.
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.
An important evidence in favour of organic evolution is the occurrence of- a)Analogous and vestigial organs
- b)Homologous organs only
- c)Homologous and analogous organs
- d)Homologous and vestigial organs
Correct answer is option 'D'. Can you explain this answer?
An important evidence in favour of organic evolution is the occurrence of
a)
Analogous and vestigial organs
b)
Homologous organs only
c)
Homologous and analogous organs
d)
Homologous and vestigial organs
|
|
Ankita Khaire answered |
D) Homologous and vestigial organs because Homologous organs show that the organism on Earth are related to its ancestors.
Vestigial organs are those organs which are functioning in ancestors but not now in there next generation for example, In ancestors of human beings
vestigial organs like vermiform appendix is in function but not in there next generation that is in today's human beings but this organ are present in there body.
Vestigial organs are those organs which are functioning in ancestors but not now in there next generation for example, In ancestors of human beings
vestigial organs like vermiform appendix is in function but not in there next generation that is in today's human beings but this organ are present in there body.
Life cannot originate from inorganic materials at present because : [CBSE 98]- a)High degree of environmental pollution
- b)A very high amount of oxygen in the atmosphere
- c)Very high atmospheric temperature
- d)Absence of raw materials
Correct answer is option 'B'. Can you explain this answer?
Life cannot originate from inorganic materials at present because : [CBSE 98]
a)
High degree of environmental pollution
b)
A very high amount of oxygen in the atmosphere
c)
Very high atmospheric temperature
d)
Absence of raw materials
|
|
Nikita Singh answered |
Oxidising atmosphere is the region that life cannot originate from inorganic materials at present. Today's atmosphere is not conducive to the spontaneous synthesis of complex molecules because the oxygen attacks chemical bonds, extracting electrons. Hence, the correct option is b.
During the course of origin of life what wa the sequence of substances which appeared on earth : [CBMT 96]- a)Water, oxygen, nucleic acids. enzymes
- b)Amino acids, ammonia, phosphates,nucleic acids
- c)Glucose, amino acids, nucleic acids, proteins
- d)Ammonia, Amino acids, proteins, nucleic acids
Correct answer is option 'D'. Can you explain this answer?
During the course of origin of life what wa the sequence of substances which appeared on earth :
[CBMT 96]
a)
Water, oxygen, nucleic acids. enzymes
b)
Amino acids, ammonia, phosphates,nucleic acids
c)
Glucose, amino acids, nucleic acids, proteins
d)
Ammonia, Amino acids, proteins, nucleic acids
|
Mayank Chavan answered |
< b="" />Sequence of Substances During the Origin of Life on Earth< />
The origin of life on Earth is still a topic of scientific investigation and debate. However, several theories propose a sequence of substances that appeared during this process. The correct answer to the given question is option 'D', which includes the sequence of substances as ammonia, amino acids, proteins, and nucleic acids. Let's explore this answer in detail:
< b="" />1. Ammonia< />
Ammonia (NH3) is a compound that consists of one nitrogen atom bonded with three hydrogen atoms. It is believed to have been present on early Earth due to volcanic activity and the presence of nitrogen gas in the atmosphere. Ammonia could have played a role in the formation of organic molecules necessary for life.
< b="" />2. Amino Acids< />
Amino acids are the building blocks of proteins. They contain both an amino group (-NH2) and a carboxyl group (-COOH) attached to a central carbon atom. Amino acids can spontaneously form under certain conditions, such as the presence of energy sources like lightning or UV radiation, and the availability of organic compounds. These organic compounds could have been synthesized from the primordial soup of ammonia, water, and other simple molecules.
< b="" />3. Proteins< />
Proteins are complex macromolecules composed of chains of amino acids. They play crucial roles in various cellular functions and are essential for life as we know it. The formation of proteins requires the linking of amino acids through peptide bonds, which can be facilitated by the presence of certain catalysts like clay minerals or iron-sulfur clusters. These catalysts could have assisted in the assembly of amino acids into proteins.
< b="" />4. Nucleic Acids< />
Nucleic acids, such as DNA and RNA, store and transmit genetic information. They are composed of nucleotide units, which consist of a sugar molecule (ribose or deoxyribose), a phosphate group, and a nitrogenous base. It is believed that nucleotides could have formed from simple organic molecules present on early Earth, such as sugars, phosphates, and nitrogenous bases. The assembly of nucleotides into nucleic acids could have occurred through various chemical reactions.
< b="" />Conclusion< />
In summary, the correct sequence of substances that appeared during the origin of life on Earth is ammonia, amino acids, proteins, and nucleic acids. While this sequence is the most widely accepted, it is important to note that the exact processes and conditions leading to the origin of life are still under investigation and subject to ongoing research and debate.
The origin of life on Earth is still a topic of scientific investigation and debate. However, several theories propose a sequence of substances that appeared during this process. The correct answer to the given question is option 'D', which includes the sequence of substances as ammonia, amino acids, proteins, and nucleic acids. Let's explore this answer in detail:
< b="" />1. Ammonia< />
Ammonia (NH3) is a compound that consists of one nitrogen atom bonded with three hydrogen atoms. It is believed to have been present on early Earth due to volcanic activity and the presence of nitrogen gas in the atmosphere. Ammonia could have played a role in the formation of organic molecules necessary for life.
< b="" />2. Amino Acids< />
Amino acids are the building blocks of proteins. They contain both an amino group (-NH2) and a carboxyl group (-COOH) attached to a central carbon atom. Amino acids can spontaneously form under certain conditions, such as the presence of energy sources like lightning or UV radiation, and the availability of organic compounds. These organic compounds could have been synthesized from the primordial soup of ammonia, water, and other simple molecules.
< b="" />3. Proteins< />
Proteins are complex macromolecules composed of chains of amino acids. They play crucial roles in various cellular functions and are essential for life as we know it. The formation of proteins requires the linking of amino acids through peptide bonds, which can be facilitated by the presence of certain catalysts like clay minerals or iron-sulfur clusters. These catalysts could have assisted in the assembly of amino acids into proteins.
< b="" />4. Nucleic Acids< />
Nucleic acids, such as DNA and RNA, store and transmit genetic information. They are composed of nucleotide units, which consist of a sugar molecule (ribose or deoxyribose), a phosphate group, and a nitrogenous base. It is believed that nucleotides could have formed from simple organic molecules present on early Earth, such as sugars, phosphates, and nitrogenous bases. The assembly of nucleotides into nucleic acids could have occurred through various chemical reactions.
< b="" />Conclusion< />
In summary, the correct sequence of substances that appeared during the origin of life on Earth is ammonia, amino acids, proteins, and nucleic acids. While this sequence is the most widely accepted, it is important to note that the exact processes and conditions leading to the origin of life are still under investigation and subject to ongoing research and debate.
Industrial melanism is an example of:- a)Drug resistance
- b)Darkening of skin due to smoke from industries
- c)Defensive adaptation of skin against UV-rays
- d)Protective resemblance with the surrounding
Correct answer is option 'D'. Can you explain this answer?
Industrial melanism is an example of:
a)
Drug resistance
b)
Darkening of skin due to smoke from industries
c)
Defensive adaptation of skin against UV-rays
d)
Protective resemblance with the surrounding
|
|
Shreya Gupta answered |
Industrial melanism is an adaptation where the moths living in the industrial areas develop melanin pigments to match their body to the soot covered surroundings.
What is common to whale, seal and shark?[2007]- a)Thick subcutaneous fat
- b)Convergent evolution
- c)Homoiothermy
- d)Seasonal migration.
Correct answer is option 'B'. Can you explain this answer?
What is common to whale, seal and shark?
[2007]
a)
Thick subcutaneous fat
b)
Convergent evolution
c)
Homoiothermy
d)
Seasonal migration.
|
Sarthak Saini answered |
The analogous organs show convergent evolution due to similar adaptation. They do not support organic evolution. Whale, seal and shark shows convergent evolution due to similar habitats.
According to Oparin, which one of the following was not present in the primitive atmosphere of the earth[2004]- a)Methane
- b)Oxygen
- c)Hydrogen
- d)Water vapour
Correct answer is option 'B'. Can you explain this answer?
According to Oparin, which one of the following was not present in the primitive atmosphere of the earth
[2004]
a)
Methane
b)
Oxygen
c)
Hydrogen
d)
Water vapour
|
Snehal Shah answered |
According to Oparin, the atmosphere of calmative earth was reducing because its atoms were most numerous and most reactive. Free oxygen was not present in significant amount.
Large quantities of H2, N2, water vapour, CO2, CH4 and NH3 were present.
Large quantities of H2, N2, water vapour, CO2, CH4 and NH3 were present.
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