Tag: biology

Questions Related to biology

Fossil $X$ can be considered to have evolved earth than fossil $Y$ if _________________.

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. $Y$ has vestigial structures that are homologous to functional structures in fossil $X$

  2. $Y$ is structurally more complex than fossil $X$

  3. $Y$ is in better state of preservation than $X$

  4. $X$ is found in lower stratum of undisturbed sedimentary rock than $Y$

Show answer
Correct Option: A

Remains of an organism of a former geological age is known as ...........

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. Fossils

  2. Coal

  3. Petroleum

  4. Both A and B

Show answer
Correct Option: A
Explanation:
Fossils are the preserved traces of the organisms of a former geological age that once existed and now they are extinct. Fossils are formed because some organisms failed to decay completely and have remained preserved till today.
  • Fossils are very important for the study of evolution and for studying classification.
  • So, the correct option is 'Fossils'.

Choose the correct answers from the alternatives given .
The fossil record offers direct evidence for common descent because you can

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. Sometimes find common ancestors

  2. Trace the ancestry of a particular group

  3. See that the types of fossils change over time

  4. All of these

Show answer
Correct Option: D
Explanation:

Fossils are the preserved remains of previously living organisms or their traces, dating from the distant past. Fossils document the existence of now-extinct species, showing that different organisms have lived on Earth during different periods of the planet's history. They can also help scientists reconstruct the evolutionary histories and ancestry of present-day species. For instance, some of the best-studied fossils are of the horse lineage. Using these fossils, scientists have been able to reconstruct a large, branching "family tree" for horses and their now-extinct relatives. 

So, the correct option is 'All of the above'.

Foot prints, trails, tracks and tunnels of various organisations made in mud are rapidly filled in with sand and covered by sediments. This is an example of which of the following types of fossil?

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. Petrified fossil

  2. Impressions

  3. Imprints

  4. Coprolites

Show answer
Correct Option: B
Explanation:

Impressions are two-dimensional imprints of an organism that doesn't contain any organic material. An impression is a clue left of the organism's biological activity, they can be formed while the organism was moving or any other biological activity.
So the correct option is 'Impressions'.

Which of the following is relatively more accurate method of determining the age of fossils?

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. Uranium-lead method

  2. Radio-carbon method

  3. Study of carbohydrates/ proteins in rocks

  4. Electron-spin resonance method

Show answer
Correct Option: A
Explanation:
  • The dating of fossils using uranium and lead is one of the oldest processes of doing so. 
  • This is also the most redefined methods of fossil-dating. 
  • This process can enable dating of fossils that are around 1 million years to over 4.5 billion years old. 
  • This process has a routine precision in the 0.1–1 per cent range and hence, can be considered the most accurate method of fossil-dating.
  • So, the correct answer is 'Uranium-lead method'.

When was the first nuclear reactor built

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. 1942

  2. 1944

  3. 1945

  4. 1947

Show answer
Correct Option: A
Explanation:

Chicago Pile 1 was the world's first nuclear reactor, built in 1942 by Nobel Prize winner Enrico Fermi. The reactor was built underneath the University of Chicago's Stagg Field football stadium. On Dec. 2, 1942, Enrico Fermi and 48 of his colleagues succeed in achieving in this reactor the world’s first man-made controlled nuclear chain reaction, thereby establishing the ability of mankind to control the release of nuclear energy. 

So the correct answer is ' 1942'.

Choose the correct answers from the alternatives given:
The first true hominids in the fossil record have been placed in the genus

biology origin and evolution of life fossilization geological time scale, extinctions and fossils concepts of evolution

  1. Aegyptopithecus

  2. Australopithecus

  3. Dryopithecus

  4. Homo

Show answer
Correct Option: B
Explanation:

Aegyptopithecus was an early primate that existed around 30 mya and it is widely believed to be ancestral to monkeys (cercopithecoids), as well as to humans and apes (hominoids). About 15 mya, primates called Dryopithecus and Ramapithecus were existing. They were hairy and walked like gorillas and chimpanzees. Ramapithecus was more man-like while Dryopithecus was more ape-like. 

Australopithecus afarensis is one of the longest-lived, widely believed and best-known early human species. Found between 3.85 and 2.95 million years ago in Eastern Africa (Ethiopia, Kenya, Tanzania), this species survived for more than 900,000 years.
 Hence, the correct answer is 'Australopithecus'.

A nitrogen fixing microbe associated with the fern Azolla in rice fields is:

biology improvement in food resources crop yield improvement food supply crop improvement methods and organisations

  1. Frankia

  2. Rhizobium

  3. Spirulina

  4. Anabaena

Show answer
Correct Option: D
Explanation:

Anabaena azollae, a cyanobacterium that lives in symbiotic association with the free-floating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen. The inoculation of cyanobacteria in rice crops significantly influences the growth of rice crop by secretion of ammonia in floodwater.

Monoculture is 

biology improvement in food resources crop yield improvement food supply crop improvement methods and organisations

  1. Growing the same crop on the same soil after every two year

  2. Growing different crop on the same soil

  3. Growing the same crop on the same soil after every three year

  4. Growing the same crop on the same soil year after year

Show answer
Correct Option: D
Explanation:

Monoculture is the agricultural practice of producing or growing a single crop, plant, or livestock species, variety, or breed in a field or farming system for a time.

So the correct option is ' Growing the same crop on the same soil year after year'.

All trees of a particular species were cut in a forest for making furniture. Which of the following acts wu be in favour of re-establishment of that forest?

biology improvement in food resources crop yield improvement food supply crop improvement methods and organisations

  1. Planting trees of those species which were not found in that forest

  2. Planting trees of those species which are still present in that forest

  3. Planting trees of different species which were not present in that forest and show a high growth rate

  4. Planting trees of same species as many as that were cut in that forest

Show answer
Correct Option: B
Explanation:

  • If the deforested forest area is replaced with only one species of trees and all other vegetation is prevented from growing back then, a monoculture forest similar to agricultural crops will be the result.
  • However, the reforestation involves planting of different lots of seed of seedlings taken from the area, often of multiple species.
  • In those areas natural regeneration of a wide variety of plant and animal species that can occur.