Tag: neo darwinism

Questions Related to neo darwinism

The phenomenon 'ontogeny repeats phylogeny' is explained by

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Recapitulation theory

  2. Inheritance theory

  3. Mutation theory

  4. Natural selection theory

Show answer
Correct Option: A
Explanation:
Biogenetic law or Recapitulation theory was given by Ernst Haeckel in 18661866. It states that 'ontogeny repeats phylogeny'. Ontogeny is the life history of an organism while phylogeny is the evolutionary history of the race of that organism. This means that an organism repeats its ancestral history during its development.
So, the correct answer is 'Recapitulation theory'.

A prezygotic isolating mechanism prevents successful

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. gamete production

  2. fertilization

  3. zygote development

  4. reproduction of hybrids

Show answer
Correct Option: C
Explanation:
Species are kept distinct from one another by prezygotic and postzygotic barriers. These barriers keep organisms of different species from mating to produce fertile offspring, acting before and after the formation of a zygote, respectively. These barriers maintain the reproductive isolation of species.
So, the correct answer is 'zygote development'

Read the given statements and select the correct ones.
(i) Swan-necked flask experiment was done by Louis Pasteur.
(ii) The early belief of the spontaneous origin of life was disproved by Louis Pasteur.
(iii) Louis Pasteur is famous for germ theory of diseases.
(iv) The idea that life originates from pre-existing life is referred to as biogenesis theory.
(v) Father Suarez was one of the greatest supporter of theory of special creation.
(vi) Cosmozoic theory of the origin of life was proposed by Richter.
(vii) The founder of 'theory of catastrophism' is Georges Cuvier.

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. (i), (ii), (iv) and (vi)

  2. (ii), (v) and (vii)

  3. (iii), (iv), (v) and (vii)

  4. (i), (ii), (iii), (iv), (v), (vi), (vii)

Show answer
Correct Option: D
Explanation:
Swan-necked flask experiment was done by Louis Pasteur, this experiment disproved the early belief of the spontaneous origin of life and he proposed the germ theory of diseases. 
Biogenesis theory states that life originates from pre-existing life.
 
Father Suarez was one of the greatest supporters of the theory of special creation.
Cosmozoic theory of the origin of life was proposed by Richter.
The founder of the 'theory of catastrophism' is Georges Cuvier.
So, the correct option is '(i), (ii), (iii),  (iv), (v), (vi), (vii)'

Using imprints from a plate with complete medium and carrying bacterial colonies, you can select streptomycin resistant mutants and prove that such mutations do not originate as adaptation. These imprints need to be used 

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Only on plates with streptomycin

  2. On plates with minimal medium

  3. Only on plates without streptomycin

  4. On plates with and without streptomycin

Show answer
Correct Option: A
Explanation:

Plates having streptomycin allow to propagate only those bacteria which are resistant to the antibiotic.

So, the correct answer is 'Only on plates with streptomycin'.

Which factor maintains the distinctive traits of species?

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Specific niche

  2. Reproductive isolation

  3. Cooperative interaction

  4. Continuous inter communication

Show answer
Correct Option: B
Explanation:

The mechanisms of reproductive isolation or hybridization barriers are a collection of mechanisms, behaviours and physiological processes, that prevent the members of two different species that cross or mate from producing offspring. These barriers maintain the integrity of a species over time, reducing or directly impeding gene flow between individuals of different species, allowing the conservation of each species characteristics. Cooperation helps in transmitting underlying genes to future generations either through increasing the reproductive successes of the individual (direct fitness) or of other individuals who carry the same genes (indirect fitness). 

Wild duck and pintail duck produce fertile offsprings only in captivity but seldom do so in natural habitats because of

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Postreproductive isolation

  2. Mechanical isolation

  3. Genetic drift

  4. Ethological isolation

Show answer
Correct Option: D
Explanation:

Ethological isolation is defined as the failure of individuals of species with recent common ancestry (i.e., related species or semispecies) to produce hybrid offspring because differences in their behaviour prevent successful mating taking place.
The mallard or wild duck (Anas platyrhynchos) is a dabbling duck which breeds throughout the temperate and subtropical Americas, Europe, Asia, and North Africa, and has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, the Falkland Islands and South Africa.
The pintail or northern pintail is a duck with wide geographic distribution that breeds in the northern areas of Europe, Asia and North America. It is migratory and winters south of its breeding range to the equator.
Ethological isolation stops their breeding in the natural habitats, whereas they breed in captivity.

Find out the organo chlorine among the following  

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. malathion, fenitrothion, parathion

  2. carbofuran, propoxur, aldicarb

  3. pyrethrin, triazines, simazine

  4. DDT, BHC, dieldrin, endosulphan.

Show answer
Correct Option: D
Explanation:

DDT is an organo chlorine. Its highly hydrophobic, colourless, crystalline solid with a weak chemical odor. BHC (Benzene hexa chloride) is another organo chlorine followed by dieldrin and endosulphan. 

Which of these is a premating isolating mechanism?

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Habitat isolation

  2. Temporal isolation

  3. Gamete isolation

  4. All of the above

Show answer
Correct Option: D
Explanation:

In order for different species to diverge from common ancestors and drive evolution, reproductive isolation must occur. There are several types of reproductive isolation that lead to speciation. 

One major type is called prezygotic isolation and it happens before fertilization occurs between gametes. Basically, prezygotic isolation keeps different species from sexually reproducing. If individuals cannot reproduce, they are considered to be different species and diverge on the tree of life. There are several types of prezygotic isolation that range from incompatibility of gametes, to behaviors that result in incompatibility, and even a type of isolation that keeps individuals from physically being able to breed.
Mechanical- Mechanical isolation is probably the simplest concept, that keeps individuals from being able to reproduce offspring with each other. Simply put, mechanical isolation is the incompatibility of sexual organs. They just do not fit together. It may be the shape of the reproductive organs not being compatible, or size differences that prohibit the individuals from coming together.In plants, mechanical isolation is a bit different. Since size and shape are irrelevant to reproduction in plants, mechanical isolation is usually due to the use of a different pollinator for the plants.
Habitat isolation- Even very closely related species have a preference of where they live and where they reproduce. Sometimes, the preferred locations of the reproductive events are not compatible and this leads to what is known as habitat isolation. Obviously, if individuals of two different species live nowhere near each other, there will be no opportunity to reproduce and reproductive isolation will lead to even more speciation.
Temporal isolation- Different species tend to have different breeding seasons. The timing of when females are fertile leads to temporal isolation. Similar species may be physically compatible, but may still not reproduce due to mating seasons being different times of the year. If the females of one species are fertile during a given month, but the males are not able to reproduce at that time of the year, then there will be reproductive isolation between the two species.
Gametic isolation- During sexual reproduction, the female egg is fused with the male sperm and together they create a zygote. If the sperm and egg are not compatible, this fertilization cannot occur and the zygote will not form. The sperm may not even be attracted to the egg due to the chemical signals released by the egg. Other times, the sperm just cannot penetrate the egg because of its own chemical make up. Either one of these reasons is sufficient enough to keep fusion from happening and the zygote will not form.

Select the correct statement.

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Heritable variation allows for evolution.

  2. Adaptive radiation allows for mutation.

  3. Crossing-over allows for mitosis.

  4. Translocation allows for DNA replication.

  5. Cellular differentiation allows for meiosis.

Show answer
Correct Option: A
Explanation:

Heritable variations serve as raw material for natural selection and accumulation of selected heritable variations over generations leads to evolution. Diversification of ancestral line into different forms is referred to as adaptive radiation. Crossing over occurs during meiosis. Translocation is the step of elongation of peptide chain during translation. Cellular differentiation leads to tissue formation; meiosis is a type of cell division. Thus, the correct answer is option A.

Two species of frogs inhabit the same fresh water pond habitat. One species of frog sings its mating song in early May, while the other species of frog sings its mating song in late June. 
These two frogs species are able to remain completely separate species due to which isolating mechanism ? 

zoology origin of life and organic evolution neo darwinism mechanism of evolution other theories of evolution

  1. Mechanical isolation

  2. Habitat isolation

  3. Behavioral isolation

  4. Gametic isolation

  5. Geographic isolation

Show answer
Correct Option: C
Explanation:
A. In mechanical isolation, the genitalia or flower parts prevent copulation or pollen transfer respectively.
B. In habitat isolation, individuals of different species do not meet for mating because they mate in different locations.
C. In behavioural isolation, individuals choose members of their own species and reject other species as mates.
D. In gametic isolation, gametes show selective attraction and acceptance in externally fertilised species.
E. Geographic isolation is same as habitat isolation in which individuals of different species do not meet for mating because they mate in different locations.
Hence the isolation shown by the frogs having different mating seasons but living in the same pond is Behavioural isolation as they are choosing members of their species only as their mates.
So, the correct answer is 'Behavioural isolation'.