Darwin's finches are an excellent example of
adaptive radiation
seasonal migration
brood parasitism
brood parasitism
A.
adaptive radiation
Adaptive radiation represents the evolution of new forms is several directions from the common anxcestral type. In 1831 Darwin got an opportunity to travel by H M S beagle for a voyage of world exploration. Beagle sailed to the Galapagos Islands, here Darwin found a living laboratory of evolution. The common birds of Galapagos Islands, the finches were markedly different from the finches of the main land. The closely related species of finches has beaks of different shapes and sizes and adapted for feeding on completely different diet showing adaptive radiation.
The transitional fossil forms, which show the characteristic of two different groups of living animals is called connecting links, eg, Archaeopteryx, Seymouria etc.
The most apparent change during the evolutionary history of Homo sapiens is traced in
loss of body hair
walking upright
shortening of the jaws
shortening of the jaws
D.
shortening of the jaws
Rounding and enlargement of cranium, ie, gradual increase in the brain size is the most apparent change during the evolutionary history of Homo sapiens
In the case of peppered moth (Biston betularia), the black-coloured form became dominant over the light-coloured form in England during the industrial revolution. This is an example of
natural selection whereby the darker forms were selected
the appearance of the darker coloured individuals due to very poor sunlight
protective mimicry
protective mimicry
A.
natural selection whereby the darker forms were selected
The given case in an example of natural selection. As a result of the struggle for existence only those organisms could survive, which have favourable variations to adapt environmental conditions on with so many variations in populations of species the struggle for existence results in survival of the fittest. The survival of the fittest is the result of selection and proliferation of only those organisms, which were most suitably adapted the environment and most successful in mating, ie, natural selection.
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the abiogenic origin of life?
They were able to reproduce
They could separate combinations of molecules from the surroundings
They were partially isolated from the surroundings
They were partially isolated from the surroundings
D.
They were partially isolated from the surroundings
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.
Given below are four statements (A-D) each with one or two blanks. Select the option which correctly fills up the blanks in two statements.
A) Wings of butterfly and birds look alike and are the results of ...... (i) .... evolution.
B) Miller showed that CH4, H2, NH3, and .....(i) ....., when exposed to electric discharge in a flask resulted in the information of ......(ii) .....
C) The vermiform appendix is a ..... (i) ..... organ and a ......(ii) ..... evidence of evolution.
D) according to Darwin evolution took place due to ....(i) ...... and .....(ii) .... of the fittest.
(D)-(i) small variations, (ii) survival, (A)-(i) convergent
(A)- (i) convergent, (B)-(i) oxygen,(ii) nucleosides
(B)-(i) water vapour, (ii) amino acids (C)-(i) rudimentary, (ii) anatomical
(B)-(i) water vapour, (ii) amino acids (C)-(i) rudimentary, (ii) anatomical
A.
(D)-(i) small variations, (ii) survival, (A)-(i) convergent
Wings of butterfly and birds look alike and are the result of convergent evolution. Miller showed that CH4, H2, NH3 and water vapour, when exposed to electric discharge in a flask resulted in the formation of amino acids.
the vermiform appendix is a vestigial organ and an anatomical evidence of evolution.
According to Darwin, evolution took place due to small variations and survival of the fittest hence, option (a) is correct.
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