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Correct option is (C) George Gaylord Simpson

Explanation: EVOLUTIONARY species concept was GIVEN by George Gaylord Simpson. According to this concept, a species is an ancestor sequence of the POPULATION that EVOLVED separately from other species and has its own evolutionary role and tendencies. This concept also includes evolution.

Right answer is (d) Demes

Best explanation: Local population of a particular area is CALLED demes. The members of two different demes of the same species can interbreed. Races are SMALL groups of species which are geographically isolated and have some genetic difference, which is CONTROLLED by GENES.

Correct option is (a) Speciation

Explanation: The process of formation of one or more species from an EXISTING species is called Speciation. It is of two TYPES, MAINLY: Divergent speciation and Transformation speciation. Speciation was one of the MAIN theories of Darwin.

Right option is (d) Typological species concept

To EXPLAIN: Typological species concept is the most accepted concept of species. According to this concept, a FIXED pattern of CHARACTERS is visible in the species of every LIVING organism. All the members of that species show maximum resemblance with this pattern.

The correct answer is (a) DEVELOPMENT of mimicry

To elaborate: One of the drawbacks of mutation theory was that it couldn’t explain the development of mimicry, the relationship between the position of nectars in FLOWER and also length of proboscis in their insect pollinators. The PROBLEM was that these cannot be IMAGINED to have developed all of a sudden.

The correct ANSWER is (c) Mutation give rise to new varieties

Easiest EXPLANATION: A number of mutations appear in NATURE and some mutations are also induced which have GIVEN rise to variations. This theory could explain both progressive and retrogressive evolution.The remaining options are against mutation theory.

The correct option is (B) False

Explanation: It is a WRONG statement. The statement should be in opposite manner i.e. mutations are random and directionless, WHEREAS DARWINISM variations are small and directional.

The CORRECT choice is (b) Saltation

For explanation: Single-step that causes LARGE mutation is CALLED saltation. It is called as such because the mutation occurs suddenly and ABRUPTLY that leads to evolution in large scale. Hugo de VRIES used this term against Darwin’s theory of evolution.

The correct answer is (a) Evening primrose

Explanation: Hugo DE VRIES proved mutation THEORY by doing EXPERIMENTS on Oenothera lamarckian, also known as evening primrose. It was from this plant; he came up with the observations. It is a complex heterozygous plant with a chromosomal aberration.

The CORRECT choice is (c) Weismann – Theory of CONTINUITY of germplasm

Easy explanation: August Weismann opposed Lamarck’s theory of inheritance of acquired characters. He put forward this theory of germplasm. It states that characters related to the GERM cells are only INHERITED, whereas the SOMATIC cells are not.

The correct option is (d) stretching of necks over many years by short-necked ones

The explanation: According to Lamarck, GIRAFFES were like horses. They only had a small neck and FORELIMBS. They lived in places where surface vegetation as very poor. So, they had to stretch their necks in order to gain food from long TREES. HENCE, they acquired long necks.

The correct choice is (b) Heterotrophs

Easy explanation: Heterotrophs were first living organisms to EVOLVE, as they originated among organic molecules and oxygen-free atmosphere. They were anaerobes capable of respiration in the absence of oxygen. They only DEPENDED on the EXISTING molecule for their NUTRITION.

The correct CHOICE is (a) True

Explanation: Darwin stated that reproductive fitness is the MAIN fitness required to SURVIVE in nature. Branching descent and natural selection are the main two concepts according to him. So, the END result to get adapted and get selected by nature is fitness.

The correct CHOICE is (c) Struggle for existence

Explanation: Struggle for existence was a concept of Darwin and not Lamarck’s. It states that every SPECIES COMPETES with the same and other species for food, shelter, etc. to survive. Whereas, the REMAINING options support Lamarck’s concept of INHERITANCE of acquired characters.

Correct answer is (d) Lamarck

Easiest explanation: According to Lamarck, the evolution of life forms had occurred but driven by USE and disuse of organs. It was AMONG Lamarck’s basic concepts. USING an organ continuously increases its development whereas disuse of it RESULTS in its degeneration.

Correct ANSWER is (a) GIRAFFES

The explanation is: Giraffes were the MAIN EXAMPLES of LAMARCK’s use and disuse theory. Giraffes continuously used their short necks to reach tall trees for leaves. So, this resulted in the elongation of their necks.

The correct CHOICE is (a) French

The best I can explain: Lamarck was a French naturalist born in 1744. He was FAMOUS for his book Philosophie Zoologique in 1809. He came up with the theory of INHERITANCE of ACQUIRED characters.

Correct option is (c) H2S

To ELABORATE: Photoautotrophs were ANAEROBIC and utilized HYDROGEN from sources other than H2O like H2S. So, no oxygen was produced and the atmosphere was kept reducing. This type of photosynthesis was MAINLY done by planktonic sulfur BACTERIA.

The correct ANSWER is (a) Thomas Malthus

Explanation: Thomas Malthus is the AUTHOR of the book Principles of population. According to him, the population grows geometrically whereas food grows only arithmetically. Charles DARWIN was inspired by this THEORY.

Correct choice is (B) Darwinian

Explanation: The two key concepts of Darwin’s THEORY of evolution was BRANCHING descent and natural selection. Nature selects the FITTEST species. Adaptive ability is inherited and has a GENETIC basis. So, they were the two major concepts.

The correct choice is (a) Chemoautotrophs

Explanation: Chemoautotrophs are the organisms that perform chemosynthesis for FOOD and SURVIVAL. They PRODUCE ORGANIC MOLECULES from inorganic molecules. They are anaerobic in nature.

The correct option is (c) Fox

The explanation is: A SCIENTIST named Fox in 1957 discovered PROTEINOID microspheres which had a primitive membrane. In his research, he heated a mixture of amino acids at temperature 130 – 180°C and poured it into cold WATER with lipids. He FOUND out that the microsphere GOT separated.

Right answer is (d) Oparin

The best I can explain: Zaug, Thomas CECH and Altman proved that RNA molecules have enzymatic activity. Ribozymes also called as RNA enzymes were ABLE to replicate or produce PRIMORDIAL RNA. It was also believed that earth was an ‘RNA world’ about 4 billion YEARS AGO.

Right answer is (b) eobionts

For explanation: It was ESTIMATED about 3.9 billion years AGO that, life originated as Eobionts (protocell). They evolved during the Precambrian era. They were anaerobic as well as heterotrophic in nature.

Correct choice is (B) Coacervates

The explanation: The first sole living organisms were Coacervates. According to Oparin, these coacervates gave RISE to a cell. Oparin’s coacervates had the ability to grow and exhibit a simple form of metabolism. But a lipid membrane and REPRODUCTION were ABSENT.

Correct choice is (a) True

To explain I would SAY: It is true that protobionts were unable to reproduce. It is because MANY chemical reactions such as decomposition of glucose TOOK place INSIDE the protobionts. This totally disallowed them to reproduce which was one of the DRAWBACKS.

Correct ANSWER is (d) macro molecules

To explain: Each and every PROTOBIONT was FORMED by a cluster of macromolecules. The basic BUILDING BLOCKS of protobionts is macromolecules. These molecules were synthesized abiotically in the primitive ocean.

The correct option is (a) LARGE colloidal drop like structures

Best EXPLANATION: Macromolecules synthesized in primitive oceans came together to form large colloidal drop like structures called protobionts. They grew up by absorbing molecules from the atmosphere. They also contained proteins, nucleic ACIDS, lipids, ETC.

Correct option is (a) NICTITATING membrane

The explanation: Vestigial organs are the organs which are PRESENT in reduced form and do not PERFORM any function in the body. Here, the nictitating membrane is an example of a vestigial organ. It is a translucent membrane that forms an inner eyelid in birds, REPTILES, and mammals.

The CORRECT answer is (d) Tasmanian tiger cat

Easy explanation: Tasmanian tiger cat belongs to Australian marsupials. The remaining options belong to PLACENTAL MAMMALS. The Tasmanian tiger cat RESEMBLES bobcat of placental mammals. They show convergent evolution.

Correct answer is (C) Convergent evolution

Explanation: It is not ADAPTIVE radiation that confirms convergent evolution. It is an adaptive CONVERGENCE that confirms convergent evolution. The REMAINING options are applicable to adaptive radiation.

Correct OPTION is (a) AUSTRALIAN marsupial

The best I can EXPLAIN: Tasmanian WOLF belongs to Australian marsupial. Adaptive radiation was the process that gave rise to a variety of marsupials in Australia. They exhibit a LARGE number of homologous organs.

Correct ANSWER is (c) Spotted cuscus

To explain I would say: Lemur resembles spotted cuscus. They appear to be similar because of the PHENOMENON called adaptive RADIATION. They have similar LOOKS and APPEARANCE but does not have a common ancestral line.

The correct answer is (b) Convergent evolution

Best explanation: Convergent evolution is the process when more than ONE adaptive radiation OCCURS in a single GEOLOGICAL isolated area. It gives rise to analogous organs. They do not show COMMON ancestry but they show evolution.

The correct option is (b) AUSTRALIAN

To explain: Australian MARSUPIALS were taken as examples of ADAPTIVE radiation. These were the marsupials which were each different from each other but had a common ancestral STOCK. They were all WITHIN the Australian island continent.

The correct option is (d) Seedeater

The BEST I can explain: It was from the seed-eating finches, many other altered forms of beak arose enabling them to be INSECT, CACTUS or fruit eaters. This LED to the discovery of ADAPTIVE radiation. Darwin’s finches are one of the best examples of this process.

The CORRECT answer is (a) Adaptive radiation

The EXPLANATION is: Adaptive radiation is a process that gave rise to a variety of species that originated from its original species. Darwin’s finches SHOW adaptive radiation. They developed different beak varieties from the seed-eating variety.

The correct choice is (B) GALAPAGOS

The best I can explain: During the VOYAGE of Darwin, he visited the Galapagos ISLAND. There, he came across different varieties of species. He saw the variations in the modification of beaks of finches.

Correct choice is (a) TRIASSIC

Best explanation: Around 3.5 crore years ago, the first dinosaurs, flying reptiles ORIGINATED. It was during the period Triassic. Jurassic was the golden age of dinosaurs WHEREAS cretaceous is the period in which the dinosaurs BECAME EXTINCT.

The CORRECT option is (c) They can indicate industrial pollution

To explain I would say: LICHENS do not grow in polluted areas, and are used to indicate industrial pollution. They GET destroyed in presence of Sulphur dioxide present in the polluted air. So, we can notice only green algae.

Right answer is (b) Extinct

Best EXPLANATION: DINOSAURS are extinct. Their fossils were discovered in Mongolia mainly Velociraptor and Protoceratops. It shows that dinosaurs existed years AGO and are now not ALIVE. Scientist say that they were destroyed by meteorites.

Right choice is (b) Animals are BURIED and preserved by NATURAL process

Explanation: Fossils are paleontological EVIDENCES or REMAINS that are useful for finding the SPECIES living their millions of years ago. Fossils only occur where animals are buried and preserved by natural process. They mainly preserved in rocks.

Right answer is (b) False

The explanation: SWEET POTATO and potato are examples of ANALOGOUS organs, whereas sweet potato and radish are the wrong examples. Since both sweet potato and radish have the same structure i.e. root modification and FUNCTION.