Evolution

Question 1

The universe is very old – almost……..billion years old

Answer 1

20

Question 2

Earth was supposed to have been formed about……. billion years back.

Answer 2

4.5

Question 3

There was no atmosphere on early earth. (4) compounds in released from molten mass covered the surface.

Answer 3

Water vapour
Methane
Carbon dioxide
Ammonia

Question 4

Life appeared……… million years after the formation of earth, i.e., almost four billion years back.

Answer 4

500

Question 5

Statemet 1: Early Greek thinkers thought units of life called spores were transferred to different planets including earth.
Statement 2: ‘Panspermia’ is still a favourite idea for some astronomers

Answer 5

Both are correct

Question 6

For a long time it was also believed that life came out of decaying and rotting matter like straw, mud, etc. This was the theory of……….

Answer 6

spontaneous generation.

Pasture showed that in pre-sterilised flasks, life did not come from killed yeast while in another flask open to air, new living organisms arose from ‘killed yeast’.

Question 7

…………. of Russia and…………. of England proposed that the first form of life could have come from pre-existing non-living organic molecules (e.g. RNA, protein, etc.) and that formation of life was preceded by chemical evolution, i.e., formation of diverse organic molecules from inorganic constituents.

Answer 7

Oparin

Haldane

Question 8

Early conditions on earth were

Answer 8

High temperature
Volcanic storms
Reducing atmosphere containing CH4, NH3, etc

Question 9

In…………. S.L. Miller, an American scientist created similar conditions in a laboratory scale

Answer 9

1953

Question 10

Statement 1: He created electric discharge in a closed flask containing CH4, H2, NH3 and water vapour at 800*C.
Statement 2: He observed formation of nucleic acids

Answer 10

1 is correct and 2 is incorrect

CH4:NH3:H2= 2:1:2

He observed formation of amino acids
Glycine Alanine Aspartic acid

Question 11

The first non-cellular forms of life could have originated…….billion years back

Answer 11

3

They would have been giant molecules (RNA, Protein, Polysaccharides, etc.).

Question 12

The first cellular form of life did not possibly originate till about………. million years ago

Answer 12

2000 million

Question 13

Theory of special creation has three connotations:

Answer 13

One, that all living organisms (species or types) that we see today were created as such.
Two, that the diversity was always the same since creation and will be the same in future also.
Three, that earth is about 4000 years old.

Question 14

………….. concluded that existing living forms share similarities to varying degrees not only among themselves but also with life forms that existed millions of years ago.

Answer 14

Charles Darwin

Question 15

The fitness, according to Darwin, refers ultimately and only to………..

Answer 15

reproductive fitness.

Those characteristics which enable some to survive better in natural conditions (climate, food, physical factors, etc.) would outbreed others that are less-endowed to survive under such natural conditions

Question 16

Alfred Wallace, a naturalist who worked in……… had also come to similar conclusions around the same time

Answer 16

Malay Archipelago

Question 17

The geological history of earth closely correlates with the biological history of earth.

Answer 17

True

Question 18

State some paleontological evidences from NCERT
(5)

Answer 18

A study of fossils in different sedimentary layers indicates
Geological period in which they existed.
Life-forms varied over time
Certain life forms are restricted to certain geological time-spans.
New forms of life have arisen at different times in the history of earth
Some of them appear similar to modern organisms

Question 19

Embryological support for evolution was also proposed by……… based upon the observation of certain features during embryonic stage common to all………. that are absent in adult.

Answer 19

Ernst Heckel

vertebrates

Question 20

Embryo of all vertebrates including human develop a row of vestigial gill slit just……… the head but it is a functional organ only in fish and not found in any other adult vertebrates

Answer 20

behind

Question 21

Statement 1: Embryological support for evolution was also proposed by Ernst Heckel was disapproved on careful study performed by Karl Ernst von Baer
Statement 2: He noted that embryos never pass through the adult stages of other animals.

Answer 21

Both are correct

Question 22

…………… and…………. are the two key concepts of Darwinian Theory of Evolution

Answer 22

Branching descent

natural selection

Question 23

………… is the end result of the ability to adapt and get selected by nature.

Answer 23

Fitness

Question 24

Before Darwin a French naturalist………. had said that evolution of life forms had occurred but driven by use and disuse of organs

Answer 24

Lamarck

Question 25

When we describe the story of this world we describe evolution as a process. And when we describe the story of life on earth, we treat evolution as a consequence of a process called natural selection

Answer 25

True

Question 26

It is possible that the work of…….. on populations influenced Darwin

Answer 26

Thomas Malthus

Question 27

Natural selection is based on certain observations which are factual (4) in NCERT

Answer 27

Natural resources are limited Populations are stable in size except for seasonal fluctuation Members of a population vary in characteristics (infact no two individuals are alike) even though they look superficially similar Most of variations are inherited

Question 28

In the first decade of twentieth century,……… based on his work on evening primrose brought forth the idea of mutations

Answer 28

Hugo deVries

Question 29

Scientific name of evening primrose

Answer 29

Oenthera lamarckiana

Question 30

Difference between Darwin and Hugo deVries (5) differences

Answer 30

Darwin Evolution is slow and gradual Large difference arises in population slowly after passing it from one generation to other Natural selection is cause of evolution Evolution is directional Darwinian variation are small and directional Hugo deVries Evolution is single step and fast Large difference arises suddenly in population Mutation is cause of evolution Evolution is non directional and random Mutations are large and random

Question 31

deVries believed mutation caused speciation and hence called it………. (single step large mutation)

Answer 31

saltation

Question 32

This principle says that allele frequencies in a population are stable and is constant from generation to generation. The gene pool (total genes and their alleles in a population) remains a constant. This is called………

Answer 32

genetic equilibrium

Question 33

Terms and conditions for maintenance of Hardy Weinberg equilibrium or genetic equilibrium (6) in NCERT

Answer 33

No genetic drift No recombination No natural selection No gene flow Yes random mating No mutation

Question 34

New genes/alleles are added to the new population and these are lost from the old population If this happens multiple times then it leads to……….. and when same change occurs by chance, it is called………….

Answer 34

Gene flow Genetic drift

Question 35

Sometimes the change in allele frequency is so different in the new sample of population that they become a different species. The original drifted population becomes founders and the effect is called………

Answer 35

founder effect.

Question 36

Natural selection can lead to 3 fates

Answer 36

Stabilisation (in which more individuals acquire mean character value) Directional change (more individuals acquire value other than the mean character value) Disruption (more individuals acquire peripheral character value at both ends of the distribution curve)

Question 37

In 1938, a fish caught in South Africa happened to be a………. which was thought to be extinct. These animals called lobefins evolved into the first……… that lived on both land and water

Answer 37

Coelacanth amphibians There are no specimens of these left with us. However, these were ancestors of modern day frogs and salamanders.

Question 38

Statement 1: The amphibians evolved into reptiles. Statement 2: They lay thick-shelled eggs which do not dry up in sun unlike those of amphibians.

Answer 38

Both are correct

Question 39

The first mammals were like………... And they were……….

Answer 39

shrews Insectivorous

Question 40

There were in………….. mammals resembling horse, hippopotamus, bear, rabbit, etc

Answer 40

South America

Question 41

Due to continental drift, when South America joined North America, these animals were overridden by North American fauna

Answer 41

True

Question 42

Due to the same continental drift pouched mammals of Australia survived because of lack of competition from any other mammal.

Answer 42

True

Question 43

The brain capacities were between 650-800cc.in

Answer 43

Homo habilis

Question 44

Fossils discovered in Java in year……….revealed the Homo erectus about 1.5 mya

Answer 44

1891

Question 45

Homo erectus had a large brain around……..

Answer 45

900cc

Question 46

The Neanderthal man with a brain size of…….. lived in near east and central Asia

Answer 46

1400cc

Question 47

Homo sapiens arose in…….. and moved across continents and developed into distinct races

Answer 47

Africa

Question 48

During……….between 75,000-10,000 years ago modern Homo sapiens arose.

Answer 48

ice age

Question 49

Pre-historic cave art developed about………years ago

Answer 49

18,000

Question 50

One such cave paintings by Pre-historic humans can be seen at………… rock shelter in……… district of Madhya Pradesh

Answer 50

Bhimbetka Raisen

Question 51

Agriculture came around……… years back and human settlements started

Answer 51

10,000

Question 52

Comparative……. and……… shows similarities and differences among organisms of today and those that existed years ago

Answer 52

Anatomy and morphology

Question 53

Statement 1: In a collection of moths made in 1850s, i.e., before industrialisation set in, it was observed that there were more white-winged moths on trees than dark-winged or melanised moths. Statement 2: In the collection carried out from the same area, but after industrialisation, i.e., in 1920, there were more dark-winged moths in the same area, i.e., the proportion was reversed.

Answer 53

Both are correct During post-industrialisation period, the tree trunks became dark due to industrial smoke and soots. Under this condition the white-winged moth did not survive due to predators, dark-winged or melanised moth survived This understanding is supported by the fact that in areas where industrialisation did not occur e.g., in rural areas, the count of melanic moths was low

Question 54

Statement 1: The evolution is not a directed process in the sense of determinism. Statement 2: Evolution is a stochastic process based on chance events in nature and chance mutation in the organisms.

Answer 54

Both are correct

Question 55

Small black birds later called……

Answer 55

Darwin’s Finches From the original seed-eating features, many other forms with altered beaks arose, enabling them to become insectivorous and vegetarian finches

Question 56

This process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called………..

Answer 56

adaptive radiation

Question 57

The melanin moths are called as

Answer 57

Biston betularia

Question 58

Selecting agent in industrial melanism was

Answer 58

Birds

Question 59

Evolution by natural selection, in a true sense would have started when non cellular forms of life with differences in metabolic capability originated on earth.

Answer 59

False CELLULAR FORMS