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All questions of Evolution for ACT Exam

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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 surrounding
b)They could separate combinations of molecules from the surroundings
c)They could maintain an internal environment
d)They were able to reproduce
Correct 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.

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?

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 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?

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.

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?

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?

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

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?

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).

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?

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?

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.

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?

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.

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?

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.....

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?

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.

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?

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?

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.

The process of evolution of different species in a given geographical area starting from a point and radiating to other geographical area is called?

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. 

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?

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.

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?

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 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?

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.........

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?

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.

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?

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.

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?

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.

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?

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?

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 mesozoic era of earth is called the :    [CPMT 84]
  • a)
    Age of amphibians
  • b)
    Age of armoured fishes 
  • c)
    Age of primitive man
  • d)
    Age of ruling reptiles 
Correct answer is option 'D'. Can you explain this answer?

Yamuna Mani answered
Mesozoic era or middle life era is the life diversified rapidly and giant reptiles,dinosaurs and other monstrous beads roamed the earth. so it is called as age of reptiles era.

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?

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.

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?

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?

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.

Theory of evolution is mainly concerend with :                           [CPMT 73]
  • a)
    Spontaneous generation
  • b)
    Theory of special creation  
  • c)
    Gradual change
  • d)
    Conditions of environment
Correct answer is option 'C'. Can you explain this answer?

Priyanka Sharma answered
Evolution is the gradual changes occurring over generations after generations, during which different species of plants, animals, birds and insects gradually change some of their physical characteristics. These changes include the different aspects of life like genetic drift, mutation, natural selection, thought and technology.The main factors responsible for the evolutionary changes are certain environmental changes and predation pressures.

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?

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.

Now the basis of origin of life is :
 [NCERT 71]
  • a)
    Spontaneous generation  
  • b)
    God's desire
  • c)
    Sunlight on mud
  • d)
    None of them
Correct answer is option 'D'. Can you explain this answer?

Surendra Bishnoi answered
Option d is correct bcz according to ncert chemicals evolution is given by oparin and Halden is most acceptable and Miller also prove this

Evolution of different species in a given area starting from a point and spreading to other geographical areas is known as
  • a)
    Migration
  • b)
    Divergent evolution
  • c)
    Adaptive radiation
  • d)
    Natural selection
Correct answer is option 'C'. Can you explain this answer?

Mansi Deshpande answered
Adaptive Radiation:

Adaptive radiation is the evolution of different species in a given area starting from a point and spreading to other geographical areas. It is a type of divergent evolution that occurs when a single ancestral species evolves into many different species to adapt to different ecological niches. The term "adaptive radiation" was coined by the American evolutionary biologist Henry Fairfield Osborn in 1897.

Factors that contribute to adaptive radiation:

1. Ecological opportunity: When new habitats or resources become available, organisms can exploit them and evolve to fill new niches.

2. Morphological innovation: Morphological innovation can allow organisms to exploit new resources or habitats.

3. Competition: Competition for resources can drive organisms to evolve different adaptations, leading to adaptive radiation.

Examples of adaptive radiation:

1. Darwin's finches: The Galápagos Islands are home to a number of different finch species that evolved from a common ancestor. Each species has a specialized beak that allows it to feed on different types of food.

2. Hawaiian honeycreepers: The Hawaiian Islands are home to a diverse group of birds known as honeycreepers. These birds evolved from a single ancestral species and have adapted to different ecological niches on the islands.

3. Australian marsupials: Australia is home to a number of different marsupial species that evolved from a common ancestor. These marsupials have adapted to different ecological niches, such as the kangaroo, koala, and Tasmanian devil.

Conclusion:

Adaptive radiation is an important process in the evolution of new species. It allows organisms to adapt to new environments and resources and can lead to the development of new ecological niches. The study of adaptive radiation can provide insights into the mechanisms of evolution and the factors that contribute to biodiversity.

Primitive atmosphere was reducing because :
  • a)
    Hydrogen atoms were few
  • b)
    Hydrogen atoms were active and in greater number
  • c)
    Nitrogen atoms were more
  • d)
    Oxygen atoms were more 
Correct answer is option 'B'. Can you explain this answer?

Shreya Saini answered
The very first atmosphere of earth was composed mostly of hydrogen atoms and these atoms due to light weight were very active. Thus,it was a reducing atmosphere during primitive time.

Theory of spontaneous generation  believed that : [NCERT  773]
  • a)
    Life of originated from othe similar organisms or spontaneously
  • b)
    life arises from the non-living matter
  • c)
    Life originated from similar organisms
  • d)
    Life originated from air
Correct answer is option 'B'. Can you explain this answer?

Mayank Chavan answered
Believers of spontaneous generation believed that life originated only spontaneously. Let's understand this statement in detail.

Explanation:
Spontaneous generation is the theory that proposed that living organisms could arise from non-living matter under certain conditions. This theory was widely accepted for many centuries, until it was disproven by Louis Pasteur in the mid-19th century.

a) Life originated from other similar organisms or spontaneously:
According to the theory of spontaneous generation, life could arise either from other similar organisms or spontaneously from non-living matter. However, this is not the correct answer as the believers of spontaneous generation did not consider the possibility of life originating from other similar organisms.

b) Life originated only spontaneously:
This is the correct answer. The believers of spontaneous generation argued that life could only originate spontaneously from non-living matter. They believed that under certain conditions, such as the presence of air, moisture, and organic material, life could arise spontaneously.

c) Life originated from similar organisms:
This is not the correct answer. The believers of spontaneous generation did not consider the possibility of life originating from similar organisms. They believed that life could only arise from non-living matter.

d) Life originated from air:
While air was considered to be one of the necessary conditions for spontaneous generation, it was not believed to be the source of life. The believers of spontaneous generation thought that life could originate from the combination of non-living matter, air, and other environmental factors.

In conclusion, the correct answer is option 'B' - the believers of spontaneous generation believed that life originated only spontaneously from non-living matter under certain conditions. However, it's important to note that this theory has been disproven by scientific experiments and observations, and the modern understanding of life's origin is based on the principles of biogenesis, which states that life only arises from pre-existing life.

Evolution of modern man is most interesting and appears parallel evolution of
  • a)
    Body height and weight
  • b)
    Human brain and language
  • c)
    Human brain and height
  • d)
    Height and body hairs
Correct answer is option 'B'. Can you explain this answer?

Awantika Gupta answered
Weight, height, hair doesn't relate with brain but language is correspondence to brain and it was the most significant evolution of human i. e. increasing cranial capacity.

Characteristics of primitive monkey which was in the direction of evolution of man :
  • a)
    Thumb parallel to fingers
  • b)
    32 teeth
  • c)
    Prehensile tail
  • d)
    Flat nose 
Correct answer is option 'B'. Can you explain this answer?

Snehal Khanna answered
Primates are heterodonts with four kinds of teeth: incisors, canines, premolars, and molars. The numbers of each kind of tooth vary by species. Humans, for example, have 8 incisors, 4 canines, 8 premolars, and 12 molars, for a total of 32 teeth.

Evolution of birds and mammals occurred in :
  [CPMT 83]
  • a)
    Eocene and oligocene periods
  • b)
    Silurian and Devonian periods  
  • c)
    Carboniferous and Permain epochs
  • d)
    Jurasic period  
Correct answer is option 'D'. Can you explain this answer?

Baishali Joshi answered
The evolution of birds and mammals occurred in Jurassic period. The earliest birds were derived from a clade of theropod dinosaurs named paraves. Mammals evolved 10 times faster in the middle of the Jurassic period.

What's the difference between natural selection and sexual selection?
  • a)
    Sexual selection is a type of natural selection
  • b)
    Sexual selection occurs during sex
  • c)
    Sexual selection occurs within demes, natural selection does not
  • d)
    Natural selection is a type of sexual selection
Correct answer is option 'A'. Can you explain this answer?

Maya Sengupta answered
Natural selection is the survival of members of species having some new traits that may help the organism in given surrounding. Sexual selection is a kind of natural selection as mating between similar organisms only leads to reproduction.

Praying mantis is a good example of
  • a)
    Warning colouration
  • b)
    Social insects
  • c)
    Mullerianmimcry
  • d)
    Camouflage
Correct answer is option 'D'. Can you explain this answer?

Lakshmi Khanna answered
< b="" />Camouflage< />

The correct answer for the given question is option 'D' - Camouflage. A praying mantis is a perfect example of an organism that uses camouflage as a defense mechanism. Camouflage refers to the ability of an organism to blend in with its surroundings, making it difficult for predators to detect or capture it. Praying mantises have evolved unique adaptations that allow them to effectively camouflage in their environment, making them highly successful predators themselves.

Adaptations for Camouflage

Praying mantises have several physical adaptations that help them camouflage effectively:

1. Body Shape: Praying mantises have an elongated body shape that resembles sticks or plant stems, allowing them to blend in with the surrounding vegetation. Their thin bodies and elongated legs further aid in mimicking plant structures.

2. Coloration: Praying mantises come in a range of colors including green, brown, and even pink. These colors help them match the color of their surroundings, whether it be leaves, twigs, or flowers. Some species can even change their coloration to match their environment.

3. Texture: The texture of a praying mantis' exoskeleton also contributes to its camouflage. The rough and uneven surface helps break up its outline, making it harder for predators to spot them.

Benefits of Camouflage

Camouflage provides several benefits to praying mantises, including:

1. Predator Avoidance: By blending in with their surroundings, praying mantises can avoid being detected by predators such as birds, lizards, and even other insects. This allows them to hide in plain sight and increases their chances of survival.

2. Ambush Predation: Praying mantises are ambush predators, relying on their camouflage to remain undetected by their prey. They patiently wait for unsuspecting insects to come within striking distance, using their cryptic coloration and immobility to remain hidden until the opportune moment.

3. Reproductive Success: Camouflage also plays a role in the reproductive success of praying mantises. Females, in particular, benefit from their camouflage as it allows them to hide from males after mating, reducing the risk of cannibalism.

In conclusion, the praying mantis is an excellent example of an organism that utilizes camouflage as a defense mechanism. Its unique adaptations in body shape, coloration, and texture allow it to blend seamlessly with its surroundings, providing benefits such as predator avoidance and successful predation.

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