Evolution

1. Which of the following is used as an atmospheric pollution indicator?

a. Lepidoptera

b. Lichens

c. Lycopersicon

d. Lycopodium

Answer: b. Lichens

Explanation: Lichens are highly sensitive to environmental changes, particularly sulfur dioxide pollution in the air. They fail to grow in polluted industrial areas, making them excellent natural indicators of air quality.

2. The theory of spontaneous generation stated that:

a. Life arose from living forms only

b. Life can arise from both living and non-living

c. Life can arise from non-living things only.

d. Life arises spontaneously, neither from living nor from the non-living.

Answer: c. life can arise from non-living things only.

Explanation: The historical theory of spontaneous generation proposed that living organisms could arise directly and rapidly from non-living, decaying, or rotting matter.

3. Animal husbandry and plant breeding breeding programmes are the examples of:

a. Reverse evolution

b. Artificial selection

c. Mutation

d. Natural selection

Answer: b. artificial selection

Explanation: These programs rely on human intervention to deliberately select and breed plants and animals for specific desirable traits. This acts as artificial selection, mimicking the process of natural selection but driven by human choice.

4. Palaentological evidences for evolution refer to the:

a. Development of embryo

b. Homologous organs

c. Fossils

d. Analogous organs.

Answer: c. fossils

Explanation: Palaeontology is the scientific study of ancient life through the examination of plant and animal fossils. Fossils provide direct historical evidence of organisms that lived in the past and how they changed over time.

5. The bones of forelimbs of whale, bat, cheetah and man are similar in structure, because:

a. One organism has given rise to another

b. They share a common ancestor

c. They perform the same function

d. The have biochemical similarities

Answer: b. they share a common ancestor

Explanation: These are homologous structures, meaning they share the same fundamental anatomical bone plan despite performing different functions (swimming, flying, running, grasping). This indicates that these mammals evolved from a shared ancestral lineage.

6. Analogous organs arise due to:

a. Divergent evolution

b. Artificial selection

c. Genetic drift

d. Convergent evolution

Answer: d. convergent evolution

Explanation: Analogous organs have different evolutionary origins but perform similar functions because different species adapted to similar environmental challenges. This process of evolving similar traits independently is known as convergent evolution.

7. (p+q)2=p2+2pq+q2=1 represents an equation used in:

a. Population genetics

b. Mendelian genetics

c. Biometrics

d. Molecular genetics

Answer: a. population genetics

Explanation: This is the Hardy-Weinberg equilibrium equation used to calculate allele and genotype frequencies within a population. It helps scientists determine whether an evolutionary change is occurring within that population.  

8. Appearance of antibiotic-resistant bacteria is an example of:

a. Adaptive radiation

b. Transduction

c. Pre-existing variation in the population

d. Divergent evolution  

Answer: c. pre-existing variation in the population

Explanation: A small number of bacteria naturally possess mutations that make them resistant to antibiotics. When antibiotics are introduced, they kill the non-resistant ones, naturally selecting the pre-existing resistant variants to survive and multiply.

9. Evolution of life shows that life forms had a trend of moving from:

a. Land to water

b. Dryland to wet land

c. Fresh water to sea water

d. Water to land

Answer: d. water to land

Explanation: Life first originated in the aquatic environments of early Earth. Over millions of years, organisms gradually evolved complex structural and physiological adaptations to survive, reproduce, and thrive on terrestrial habitats.

10. Viviparity is considered to be more evolved because:

a. The young ones are left on their own

b. The young ones are protected by a thick shell

c. The young ones are protected inside the mother's body and are looked after they are born leading to more chances of survival

d. The embryo takes a long time to develop

Answer: c. the young ones are protected inside the mother's body and are looked after they are born leading to more chances of survival

Explanation: Internal embryonic development protects the offspring from external environmental hazards and predators. Coupled with post-natal parental care, this reproductive strategy significantly increases the survival rate of the young.

11. Fossils are generally found in:

a. Sedimentary rocks

b. Igneous rocks

c. Metamorphic rocks

d. Any type of rock

Answer: a. Sedimentary rocks

Explanation: Fossils form when dead organisms are quickly buried by sediment (like mud or sand), which over millions of years compresses into rock. The intense heat of igneous rocks and extreme pressure of metamorphic rocks usually destroy organic remains.

12. For the MN-blood group system, the frequencies of M and N alleles are 0.7 and 0.3, respectively. The expected frequency of MN-blood group bearing organisms is likely to be

a. 42%

b. 49%

c. 9%

d. 58%

Answer: a. 42%

Explanation: Using the Hardy-Weinberg equation, the frequency of the heterozygous MN genotype is calculated as 2pq. Substituting the values (2 \times 0.7 \times 0.3) yields 0.42, which equals 42\%.  

13. Which type of selection explains industrial melanism observed in moth, Biston bitularia:

a. Stabilising

b. Directional

c. Disruptive

d. Artificial  

Answer: b. Directional

Explanation: Industrial pollution darkened the tree trunks, favoring the survival of dark-winged moths over light-winged ones. This shifted the population's phenotype continuously in one specific direction (towards darker coloration).

14. The most accepted line of descent in human evolution is:

a. Australopithecus → Ramapithecus (Homo sapiens → Homo habilis)

b. Homo erectus → Homo habilis Homo sapiens

c. Ramapithecus → Homo habilis → Homo erectus → Homo sapiens

d. Australopithecus → Ramapithecus → Homo erectus → Homo habilis → Homo sapiens.

Answer: c. Ramapithecus → Homo habilis → Homo erectus → Homo sapiens

Explanation: While the text options are slightly truncated, the scientifically accepted chronological sequence progresses from early ape-like ancestors (Ramapithecus/Australopithecus) to the tool-making Homo habilis, the upright Homo erectus, and finally modern Homo sapiens. Option 'c' provides the most accurate forward progression available in the choices.

15. Which of the following is an example for link species?

a. Lobe fish

b. Dodo bird

c. Sea weed

d. Chimpanzee

Answer: a. Lobe fish

Explanation: Lobe-finned fish, such as the Coelacanth, are considered a transitional evolutionary link between aquatic fishes and the earliest terrestrial amphibians. Their stout, bone-supported fins represent a precursor to tetrapod limbs.

16. Match the scientists listed under column 'I with ideas listed column 'II'.

a. A-i; B-iv; C-ii; D-iii

b. A-iv; B-i; C-ii; D-iii

c. A-ii; B-iv; C-iii; D-i

d. A-iv; B-iii; C-ii; D-i

Answer: b. A-iv; B-i; C-ii; D-iii (or d, as both correctly map A to iv)

Explanation: Charles Darwin (A) is famously credited with proposing the theory of evolution by natural selection (iv). Any correct matching sequence must pair these two together.

17. In 1953 S. L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for origin of first form of life from pre-existing non-living organic molecules. The primitive earth conditions created include:

a. Low temperature, volcanic storms, atmosphere rich in oxygen

b. Low temperature, volcanic storms, reducing atmosphere

c. High temperature, volcanic storms, non-reducing atmosphere

d. High temperature, volcanic storms, reducing atmosphere containing CH4, NH3 etc.

Answer: d. high temperature, volcanic storms, reducing atmosphere containing CH4, NH3 etc.

Explanation: The early Earth lacked free oxygen (a reducing atmosphere) and was subject to high temperatures and lightning. Miller's spark-discharge experiment successfully simulated these harsh conditions using methane, ammonia, hydrogen, and water vapor to create amino acids.

18. Variations during mutations of meiotic recombinations are:

a. Random and directionless

b. Random and directional

c. Small and directional

d. Random, small and directional

Answer: a. random and directionless

Explanation: Genetic mutations occur by chance and are not driven by the specific needs or external environment of the organism. Because they do not inherently push an organism toward a specific goal, they are considered random and directionless.