View all 258 cards in this deck

#	Question	Answer
1	What is Evolutionary Biology?	The study of the history of life forms on Earth.
2	What is the estimated age of the universe?	About 13.8 billion years.
3	What theory explains the origin of the universe?	The Big Bang Theory.
4	According to the Big Bang Theory, which two gases formed first?	Hydrogen and Helium.
5	How were galaxies formed?	Gases condensed under gravitation.
6	When was Earth formed?	About 4.5 billion years ago.
7	Was there an atmosphere on early Earth?	No, early Earth had no atmosphere initially.
8	Which gases were released from the molten mass of early Earth?	Water vapour, methane, carbon dioxide, and ammonia.
9	What happened to hydrogen formed from water breakdown?	The lighter hydrogen escaped into space.
10	Which atmospheric layer formed later on Earth?	The ozone layer.
11	How were oceans formed on Earth?	Water vapour cooled and fell as rain, filling depressions.
12	When did life first appear on Earth?	About 4 billion years ago.
13	What is the Panspermia theory?	The idea that life came to Earth from outer space as spores.
14	What is spontaneous generation theory?	The belief that life originated from decaying matter.
15	Who disproved spontaneous generation experimentally?	Louis Pasteur.
16	What did Louis Pasteur demonstrate?	Life comes only from pre-existing life.
17	Who proposed the chemical evolution theory?	Oparin and Haldane.
18	According to Oparin and Haldane, life originated from what?	Pre-existing non-living organic molecules.
19	What is chemical evolution?	Formation of organic molecules from inorganic constituents.
20	Who performed the famous experiment supporting chemical evolution in 1953?	S. L. Miller.
21	What other compounds were formed in similar experiments?	Sugars, nitrogen bases, pigments, and fats.
22	What were the first non-cellular forms of life likely made of?	Giant molecules like RNA, proteins, and polysaccharides.
23	When did the first non-cellular forms of life originate?	About 3 billion years ago.
24	When did the first cellular forms of life appear?	About 2000 million years ago.
25	What was the probable nature of the first cellular organisms?	Single-celled organisms.
26	In which environment did all early life forms exist?	Water environment only.
27	What is biogenesis according to the text?	Life arose slowly from non-living molecules through evolutionary forces.
28	What were the first cellular forms of life probably like?	Single-celled organisms.
29	In which environment did all early life forms exist?	Water environment.
30	What does biogenesis explain?	Life arose gradually from non-living molecules through evolutionary forces.
31	What theory is mentioned in religious literature regarding origin of life?	Theory of Special Creation.
32	According to the theory of Special Creation, how were organisms created?	All organisms were created in their present form.
33	What does the theory of Special Creation say about biodiversity?	Diversity has remained the same since creation and will remain unchanged.
34	Which scientist challenged the theory of Special Creation during the 19th century?	Charles Darwin.
35	Name the ship on which Darwin travelled around the world.	H.M.S. Beagle.
36	What did Darwin conclude from his observations?	Existing life forms share similarities with extinct life forms.
37	What did Darwin observe regarding extinct organisms?	Many life forms that existed earlier no longer exist today.
38	What process explains gradual changes in life forms over time?	Evolution.
39	What is variation in a population?	Differences in characteristics among individuals of a population.
40	Which characteristics help organisms survive better?	Characteristics suited to natural conditions like climate and food.
41	Which organisms leave more progeny?	Better fit organisms.
42	What mechanism of evolution was proposed by Darwin?	Natural selection.
43	Which naturalist independently reached conclusions similar to Darwin?	Alfred Wallace.
44	What do all existing life forms share according to Darwin?	Common ancestors.
45	What closely correlates with the biological history of Earth?	Geological history of Earth.
46	What is a fossil?	Remains of hard parts of organisms found in rocks.
47	What type of evidence do fossils provide for evolution?	Paleontological evidence.
48	What do sedimentary rock layers indicate?	Different geological periods and life forms existing at that time.
49	What do fossils in different sedimentary layers show?	Life forms varied over time.
50	What do fossils of dinosaurs represent?	Extinct organisms.
51	What does paleontology study?	Fossils and ancient life forms.
52	Who proposed embryological evidence for evolution?	Ernst Haeckel.
53	What embryological feature is common in vertebrate embryos?	Vestigial gill slits behind the head.
54	In which vertebrate are gill slits functional in adults?	Fish.
55	What did Karl Ernst von Baer conclude about embryos?	Embryos never pass through adult stages of other animals.
56	What does comparative anatomy study?	Similarities and differences among organisms.
57	What can similarities among organisms indicate?	Common ancestry.
58	What do similarities among organisms help scientists determine?	Whether organisms share common ancestors.
59	Which animals are mentioned as having similar forelimb bone patterns?	Whales, bats, cheetah, and humans.
60	Which type of organs have similar structure but different functions?	Homologous organs.
61	Name the bones common in forelimbs of whales, bats, cheetah, and humans.	Humerus, radius, ulna, carpals, metacarpals, and phalanges.
62	What does homology indicate?	Common ancestry.
63	What is divergent evolution?	Evolution in which the same structure develops differently due to different adaptations.
64	Give one example of homologous organs in plants.	Thorn of Bougainvillea and tendril of Cucurbita.
65	Homology is based on which type of evolution?	Divergent evolution.
66	What is analogy in evolution?	Different structures performing similar functions.
67	Which structures are examples of analogous organs?	Wings of butterfly and birds.
68	Why are butterfly wings and bird wings called analogous organs?	They perform similar functions but differ anatomically.
69	Analogous structures are a result of which type of evolution?	Convergent evolution.
70	Why do unrelated organisms develop similar adaptive features?	Due to similar habitat conditions.
71	Why are sweet potato and potato considered analogous?	Sweet potato is a root modification while potato is a stem modification, but both perform similar functions.
72	What do similarities in proteins and genes among organisms suggest?	Common ancestry.
73	What kind of evidence do biochemical similarities provide?	Evidence for shared ancestry.
74	Why has man selectively bred plants and animals?	For agriculture, horticulture, sport, and security.
75	What has intensive breeding by humans produced?	Different breeds within the same group.
76	What evolutionary argument is supported by artificial selection?	Nature could create new forms over millions of years.
77	Which observation from England supported natural selection?	Industrial melanism in moths.
78	Before industrialisation, which moths were more common?	White-winged moths.
79	After industrialisation, which moths became more common?	Dark-winged or melanised moths.
80	Why did dark-winged moths survive after industrialisation?	Tree trunks became dark due to soot, helping them camouflage.
81	Why did white-winged moths survive before industrialisation?	Trees were covered with light-coloured lichens.
82	What role did predators play in industrial melanism?	Predators spotted moths against contrasting backgrounds.
83	What are lichens used as indicators of?	Industrial pollution.
84	Why do lichens not grow in polluted areas?	They are sensitive to pollution.
85	What does the moth example demonstrate about evolution?	Better-adapted variants survive and increase in population.
86	What effect has excessive use of herbicides and pesticides caused?	Selection of resistant varieties.
87	What is observed in microbes due to antibiotic use?	Appearance of resistant strains.
88	What are examples of evolution caused by human activities called?	Evolution by anthropogenic action.
89	Is evolution a directed deterministic process?	No, it is a stochastic process based on chance events and mutations.
90	Which islands did Darwin visit during his journey?	Galapagos Islands.
91	What amazed Darwin about the finches?	The presence of many varieties of finches on the same island.
92	According to Darwin, from where did the finch varieties evolve?	From the original finches on the island itself.
93	What is adaptive radiation?	Evolution of different species from a common ancestor in a geographical area into different habitats.
94	Which mammals are another example of adaptive radiation?	Australian marsupials.
95	What evolved from a common ancestral stock in Australia?	Different marsupials.
96	Where did adaptive radiation of marsupials occur?	Australian island continent.
97	What is convergent evolution according to the text?	Evolution of similar adaptive features in unrelated groups in isolated areas.
98	Which mammals in Australia also show adaptive radiation?	Placental mammals.
99	Why are placental mammals and marsupials compared?	They evolved similar forms independently.
100	Give one example of similarity between placental mammals and marsupials.	Placental wolf and Tasmanian wolf.
101	What is the essence of Darwinian theory of evolution?	Natural selection.
102	When did evolution by natural selection truly begin?	When cellular life forms with metabolic differences originated.
103	What is linked to the rate of appearance of new forms?	Life cycle or life span.
104	Why do microbes evolve rapidly?	They divide fast and multiply quickly.
105	What happens when the environment changes in a bacterial colony?	Only variants suited to new conditions survive.
106	What eventually happens to better-adapted bacterial variants?	They outgrow others and appear as new species.
107	How long may speciation take in microbes?	Within days.
108	Why does evolution take much longer in fish or fowl?	Their life spans are longer.
109	What does nature select according to Darwin?	Fitness.
110	What is necessary for organisms to evolve through natural selection?	A genetic basis for inherited characteristics.
111	What is adaptive ability?	Ability to survive in hostile environments.
112	Is adaptive ability inherited?	Yes.
113	What are the two key concepts of Darwinian theory?	Branching descent and natural selection.
114	What marks the true beginning of evolution by natural selection?	Origin of cellular forms of life with metabolic differences.
115	What is the essence of Darwinian theory of evolution?	Natural selection.
116	On what is the rate of appearance of new forms dependent?	Life cycle or life span.
117	Why can microbes evolve rapidly?	They divide quickly and produce millions within hours.
118	What exists within a bacterial colony growing on a medium?	Built-in variation in ability to utilise feed components.
119	What happens when the medium composition changes?	Only variants adapted to the new conditions survive.
120	What eventually happens to surviving bacterial variants?	They outgrow others and may appear as a new species.
121	How quickly can speciation occur in microbes?	Within days.
122	Why does evolution take millions of years in fish or fowl?	Their life spans are much longer.
123	What does Darwinian fitness mean?	Better survival and reproductive success under given conditions.
124	What does nature select according to Darwin?	Fitness.
125	What is required for natural selection to cause evolution?	A genetic basis for inherited characteristics.
126	What is adaptive ability?	Ability to survive in a hostile environment.
127	Is adaptive ability inherited?	Yes, it has a genetic basis.
128	What are the two key concepts of Darwinian evolution?	Branching descent and natural selection.
129	Which scientist proposed evolution through use and disuse of organs?	Lamarck.
130	Which example did Lamarck give to explain evolution?	Evolution of long necks in giraffes.
131	According to Lamarck, how did giraffes acquire long necks?	By stretching to reach leaves on tall trees and passing the acquired trait to offspring.
132	Why is there competition for resources in nature?	Natural resources are limited.
133	How are population sizes generally maintained in nature?	They remain stable except for seasonal fluctuations.
134	Are individuals in a population exactly alike?	No, variations exist among them.
135	Are most variations inherited?	Yes.
136	What would happen if every organism reproduced maximally?	Population size would grow exponentially.
137	Why do population sizes remain limited despite reproductive potential?	Due to competition for resources.
138	Which organisms survive and reproduce more successfully?	Organisms with heritable variations better suited to the habitat.
139	What happens over many generations due to natural selection?	Population characteristics change and new forms arise.
140	What is mutation according to Hugo de Vries?	Large difference arising suddenly in a population; he called it saltation (single step large mutation).
141	On which plant did Hugo de Vries conduct his studies?	Evening primrose.
142	According to de Vries, what causes evolution?	Mutations.
143	How are mutations described by de Vries?	Random and directionless.
144	How did Darwin describe variations?	Small and directional.
145	What is saltation?	Speciation caused by a single-step large mutation.
146	How did Darwin view evolution?	As a gradual process.
147	Which field later clarified ideas about evolution and mutation?	Population genetics.
148	What can be determined in a population regarding a gene?	Frequency of occurrence of alleles of a gene or locus.
149	According to Hardy-Weinberg principle, how do allele frequencies behave across generations?	They remain stable and constant from generation to generation.
150	What is the gene pool?	Total genes and their alleles in a population.
151	What is genetic equilibrium?	A condition where allele frequencies remain constant in a population.
152	What is the sum total of all allelic frequencies in a population?	1.
153	Which symbols commonly represent allele frequencies?	p and q.
154	In a diploid organism, what does p represent?	Frequency of allele A.
155	In a diploid organism, what does q represent?	Frequency of allele a.
156	What is the frequency of heterozygous Aa individuals?	2pq.
157	What does deviation from expected Hardy-Weinberg frequencies indicate?	Evolutionary change.
158	What does disturbance in genetic equilibrium result in?	Evolution.
159	Name the five factors affecting Hardy-Weinberg equilibrium.	Gene migration, genetic drift, mutation, genetic recombination, and natural selection.
160	What happens during gene migration?	A section of population moves to another place, changing gene frequencies.
161	What effect does migration have on populations?	New alleles are added to one population and lost from another.
162	What is gene flow?	Repeated gene migration between populations.
163	What is genetic drift?	Random change in allele frequencies by chance.
164	What may happen if allele frequency changes greatly in a new population?	The population may become a different species.
165	What is founder effect?	Effect produced when a small drifted population forms a new population.
166	What do microbial experiments demonstrate about mutations?	Advantageous pre-existing mutations can produce new phenotypes when selected.
167	What can occur over generations due to selected advantageous mutations?	Speciation.
168	What is natural selection?	Process in which heritable variations enabling better survival reproduce more successfully.
169	Which processes can cause changes in gene and allele frequencies?	Mutation, recombination, gene flow, and genetic drift.
170	How does natural selection influence populations?	By enhancing reproductive success of better-adapted individuals.
171	What is stabilising natural selection?	Selection in which more individuals acquire mean character value.
172	What is directional natural selection?	Selection in which more individuals acquire values away from the mean.
173	What is disruptive natural selection?	Selection in which more individuals acquire extreme character values at both ends.
174	What does natural selection combined with genetic variation produce?	Different populations and evolutionary change.
175	What is interpreted as evolution in population genetics?	Change in allele frequencies in a population over generations.
176	When did the first cellular forms of life appear on Earth?	About 2000 million years ago (mya).
177	Is the mechanism of evolution from non-cellular macromolecules to cells fully understood?	No, it is not known.
178	Which modern process resembles the oxygen-releasing reaction of early cells?	Light reaction of photosynthesis.
179	What happens during the light reaction of photosynthesis?	Water is split using solar energy captured by pigments.
180	What major change occurred after single-celled organisms evolved?	Evolution of multicellular life forms.
181	By around 500 mya, which organisms had evolved?	Invertebrates.
182	When did jawless fishes probably evolve?	Around 350 mya.
183	Which plants existed around 320 mya?	Seaweeds and a few plants.
184	Which organisms first invaded land?	Plants.
185	When did animals invade land?	After plants became widespread on land.
186	Which fish were capable of moving onto land?	Fish with stout and strong fins.
187	Around when did fishes begin moving on land?	About 350 mya.
188	Which living fossil fish was discovered in South Africa in 1938?	Coelacanth.
189	What are lobefins believed to have evolved into?	First amphibians.
190	Where did the first amphibians live?	Both on land and in water.
191	Which modern animals are descendants of early amphibians?	Frogs and salamanders.
192	Which group evolved from amphibians?	Reptiles.
193	What adaptation in reptiles prevented eggs from drying?	Thick-shelled eggs.
194	Name some modern descendants of reptiles mentioned in the text.	Turtles, tortoises, and crocodiles.
195	Which plants formed coal deposits over time?	Giant ferns (pteridophytes).
196	Which reptiles returned to water and evolved into fish-like reptiles?	Ichthyosaurs.
197	Around when did fish-like reptiles evolve?	About 200 mya.
198	Which reptiles dominated the Earth for nearly 200 million years?	Dinosaurs.
199	Name the largest dinosaur mentioned in the text.	Tyrannosaurus rex.
200	Approximately how tall was Tyrannosaurus rex?	About 20 feet.
201	What kind of teeth did Tyrannosaurus rex possess?	Huge fearsome dagger-like teeth.
202	When did dinosaurs disappear from Earth?	About 65 mya.
203	What are some suggested reasons for dinosaur extinction?	Climatic changes or evolution into birds.
204	What were the first mammals like?	Small and shrew-like.
205	What reproductive feature distinguished mammals?	Viviparity and protection of unborn young inside the body.
206	Why were mammals considered more successful than reptiles?	They were more intelligent in sensing and avoiding danger.
207	What happened when reptiles declined?	Mammals took over the Earth.
208	Which geological process affected mammalian distribution between South and North America?	Continental drift.
209	Why did pouched mammals survive in Australia?	Due to lack of competition from other mammals.
210	Name aquatic mammals mentioned in the text.	Whales, dolphins, seals, and sea cows.
211	Which evolutionary story is described as the most successful?	Evolution of humans with language skills and self-consciousness.
212	Which primates existed about 15 mya?	Dryopithecus and Ramapithecus.
213	What physical feature characterized Dryopithecus and Ramapithecus?	They were hairy and walked like gorillas and chimpanzees.
214	Which primate was considered more man-like?	Ramapithecus.
215	Which primate was considered more ape-like?	Dryopithecus.
216	In which countries were man-like fossils discovered?	Ethiopia and Tanzania.
217	What did the fossils from Ethiopia and Tanzania reveal?	Hominid features.
218	Around when did man-like primates walk in eastern Africa?	About 3–4 mya.
219	What was the approximate height of early man-like primates?	Less than 4 feet tall.
220	How did early man-like primates move?	They walked upright.
221	Which group probably lived in East African grasslands about 2 mya?	Australopithecines.
222	What evidence exists regarding Australopithecines?	They hunted with stone weapons.
223	What was the primary diet of Australopithecines?	Fruits.
224	What was the first human-like being called?	Homo habilis.
225	What was the brain capacity of Homo habilis?	About 650–800 cc.
226	Did Homo habilis probably eat meat?	No.
227	Which species was discovered in Java in 1891?	Homo erectus.
228	When did Homo erectus exist?	About 1.5 mya.
229	What was the approximate brain size of Homo erectus?	Around 900 cc.
230	What dietary habit is associated with Homo erectus?	They probably ate meat.
231	What was the brain size of Neanderthal man?	About 1400 cc.
232	Where did Neanderthal man live?	Near East and Central Asia.
233	When did Neanderthal man live?	Between 100,000–40,000 years ago.
234	What did Neanderthal men use to protect their bodies?	Animal hides.
235	What cultural practice is associated with Neanderthals?	They buried their dead.
236	Where did Homo sapiens arise?	Africa.
237	What happened after Homo sapiens arose in Africa?	They migrated across continents and formed distinct races.
238	During which period did modern Homo sapiens arise?	Ice age (75,000–10,000 years ago).
239	When did prehistoric cave art develop?	About 18,000 years ago.
240	Where is a famous prehistoric cave painting site mentioned in the text?	Bhimbetka rock shelter, Raisen district, Madhya Pradesh.
241	Around when did agriculture begin?	About 10,000 years ago.
242	What major development followed the beginning of agriculture?	Human settlements started.
243	What must be understood to explain the origin of life on Earth?	The origin of the universe, especially Earth.
244	What do most scientists believe preceded the first cellular forms of life?	Chemical evolution and formation of biomolecules.
245	How has biodiversity on Earth changed over time?	Diversity of life forms has changed over millions of years.
246	What results in variable fitness within a population?	Variations in a population.
247	Which processes may accentuate variations and lead to new species?	Habitat fragmentation and genetic drift.
248	What is the significance of homology in evolution?	It supports the idea of branching descent.
249	Which fields provide evidence for evolution according to the summary?	Comparative anatomy, fossils, and comparative biochemistry.
250	Evolution of the human brain and language parallels the evolution of what?	Modern humans.
251	Which theory explains evolution through natural selection?	Darwinian theory.
252	What type of evolution is linked with the formation of biomolecules?	Chemical evolution.
253	What is the role of genetic drift in evolution?	It accentuates variations leading to evolution.
254	What does branching descent explain?	Homology among organisms.
255	Why are fossils important in evolutionary studies?	They provide evidence of changes in life forms over time.
256	Which scientific comparison supports evolution at the molecular level?	Comparative biochemistry.
257	What is one major outcome of variations in populations?	Emergence of new species.
258	What does the summary identify as the accepted explanation for the first cellular life?	Biomolecules formed through chemical evolution before cellular life appeared.