The basic structural and functional unit of cellular organisms is the cell. The cell is capable of independent existence, Anton van Leeuwenhoek was the first person to observe living cells under the microscope. The cells are of two types, prokaryotic cells, and eukaryotic cells.
Question 1: What is the nature of the plasma membrane?
2) Selectively permeable
4) None of these
Explanation: The plasma membrane is selectively permeable means it allows some solutes to pass through not all, the cell is the very important part so it is protected by a plasma membrane.
Question 2: What is the most abundant phospholipid found in the plasma membrane?
4) All of the above
Explanation: Glycerophospholipids are the most abundant phospholipids, they are of two types depending upon the type of alcohol attached to it, phosphatidylcholine and phosphatidylserine.
Question 3: What is the simplest glycolipid in the plasma membrane?
Explanation: Glycolipids contain carbohydrates covalently attached to the lipids. The cerebroside is the simplest glycolipid it contains a single sugar residue, either glucose and galactose. Gangliosides are the most complex glycolipid.
Question 4: What is the importance of Handicap Theory?
1) Directional selection
2) Introduces homozygosity
3) Evolved from common ancestors
4) The costly character reduces the survival of the individual but increases sexual survival
Explanation: Darwin was first to realize the importance of sexual selection so gave the theory called handicap theory. In peacocks long tails actually reduce the survival advantage and increase reproductive success so peacocks have long tails because they attract the female, it is called the handicap theory.
Question 5: The Unrelated organism having a common structure and same function is called?
1) Divergent evolution
3) Adaptive radiation
4) Convergent evolution
Explanation: The convergent evolution describes the common function among unrelated organisms and the example of it is the streamlined shape of sharks and dolphins. The dolphin is a mammal and the shark is fish, they both are unrelated but a streamlined body is an advantage for both of them.
Question 6: The case of galapagos island where many related species evolved from single ancestral species is the case of?
1) Parallel evolution
2) Adaptive radiation
4) Convergent evolution
Explanation: Adaptive radiation is the case of galapagos island, where Darwin finches were studied, where a small number of species diversifies to a large number of descendents species, which occupy large ecological niches.
Question 7: Which of the following is not true about the Hardy- Weinberg law?
1) The mating occurs in a random population
2) The hardy weinberg population show various kinds of mutations
3) The frequency distribution will not change from generation to generation
4) Allelic frequency will not change from one generation to the next
Explanation: The hardy Weinberg states that the population always remains in the state of equilibrium so there should be no mutations, no genetic drift, no chromosomal aberrations and natural selection. Only then can the population remain in the state of equilibrium.
Question 8: The mechanism through which the population enters into the reproductive isolation within the range of parent species is called?
1) Parapatric speciation
2) Allopatric speciation
3) Sympatric speciation
4) None of these
Explanation: In parapatric speciation, the population is continuous but it does not reproduce randomly and it starts mating with the neighbouring population so gene flow reduces and two different species become formed.
Question 9: Which of the following mechanisms is Non- Random, Predictable and directional?
1) Genetic drift
2) Natural selection
3) Founder effect
Explanation: Natural selection is defined as the process through which the population which is best adapted to the environment increases in number and less adapted population decreases in number, natural selection can be positive and negative but it has a particular direction.
Question 10: Name of the theory that has been suggested by motoo kimura?
1) Neutral theory of molecular evolution
2) Large fraction of molecular mutations do not have an effect on evolutionary fitness
3) Evolutionary relationship among the group is represented by the two dimensional model
4) None of the above
Explanation: The neutral theory of molecular evolution is given by motoo kimura which claims that evolutionary changes are not caused by advantageous mutations only, but by the cumulative effect of all the mutations that happened.