CSIR NET Life science June 2013 - Practice Questions

1. An example of a mutagenic agent is
  • an amine
  • acetylcholine
  • ultraviolet light
  • sulfer dioxide
2. Kernal color is a traite etermined by two alleles. The dominant allele (P) produces a purple color and the recessive allele (p) produces a yellow color. Purple kernels and yellow kernals can best be described respectively as
  • heterozygous dominant and homozygous recessive
  • homozygous recess and heterozygous dominant or homozygous dominant
  • homozygous recessive or heterozygous dominant
  • heterozygous dominant or homozygous dominant and homozygous recessive
3. The genetic process by which alleles are transferred to complementary chromatids at the same or very similar times producing genetic variability within the organism for the possibility of future genetic variability within that organism’s population is called what?
  • chromosomal mutation
  • nondisjunction
  • independent assortment
  • crossing-over
4. A DNA nucleotide may contain
  • deoxyribose, cytosine, lipid
  • deoxyribose, thymine, phosphate
  • ribose, uracil, polypeptide
  • ribose, adenine, phosphate
5. Fossils of an extinct species of giant armadillo were found to be similar to a smaller species of armadillo presently inhabiting the same region. This similarity could best be explained on the basis of
  • evolution from older forms
  • inheritence of acquired characteristics
  • use and disuse
  • the heterotroph hypothesis
6. A study of the position and shape of the bones in the forelimbs of a flying squirrel, a bat and a beaver showed that the beaver and the flying squirrel appear to be most closely related. This determination was most likely based on a study in the field of comparative
  • cytogenetics
  • embryology
  • biochemistry
  • physical anatomy
7. By simulating conditions thought to have existed on a primitive Earth, Stanley Miller found that these conditions could result in the formation of
  • today’s genetic molecules
  • viral-like proteins
  • organic compounds
  • autotrophic molecules
8. According to the diagram pictured below, humans most closely relate to

  • the ancestral primate
  • chimpanzees
  • gorillas
  • orangutans
9. August Weismann conducted a series of experiments involving the removal of the tails of from several generations of mice. Which concept of LaMarckian evolution did he help disprove?
  • natural selection
  • gradualism
  • inheritence of acquired traits
  • geographic isolation
10. Modern evolutionary theory consists of the concepts of Darwin modified by knowledge concerning
  • population statistics
  • Mendel’s laws
  • the idea of the survival of the fittest
  • competition
1. ultraviolet light
2. heterozygous dominant or homozygous dominant and homozygous recessive
3. crossing-over
4. deoxyribose, thymine, phosphate
5. evolution from older forms
6. physical anatomy
7. organic compounds
8. chimpanzees
9. inheritence of acquired traits
10. Mendel’s laws