Evolutionary Biology of Plants — DU B.Sc. (Hons.) Botany Previous Year Question Papers

1. (a) Define the following (any five) : (1x) ") (i) Allopatric Speciation (ili) Homologous organs (iv) Bottleneck effect (v) Convergence in evolution (vi) Genetic Drift (b) Match the following : (1x5=5) (i) The Origin of (a) Presence/Absence of Species leaf gap (11) Stelar Evolution (b) Convergent evolution (iv) Analogous organs (d) Jean B Lamarck (V) Theory of (e) Oparin and Haldane Transformism Theory (c) Fill in the blanks (any five) (1x5=5) (i) occurs to form a fossil when cell walls become completely replaced by minerals. (1i) Natural selection is influenced by (iii) According to the — -, in a large, random-mating population, the genotype and allele frequencies remain constant in the absence of any evolutionary influences from one generation to another. (iv) - predicts that new species evolve when a large evolutionary change takes place in short periods of time. (V) . is the evolution of species caused by the geographical isolation of two or more populations of same species in an isolated geographical area. (vi) is the flow of alleles from one generation to another by means of migration or dispersion. 2. Write short notes (any three) (3xS=15) (i) Types of Stratigraphy (ii) Natural Selection (a) Differentiate between the following (any three) (i) Chemogeny and Biogeny (ii) Darwinism and Lamarckism (iii) Parallel evolution and convergent evolution (iv) Anagenesis and Cladogenesis (b) Explain the Hardy-Weinberg Principle including its limitations. (6) (a) Discuss the anthropogenic causes of evolution and extinction in detail. (b) Explain the evolution of seed and seed habit. (a) Discuss phylogenetic evidence of evolution in plants. (7.5) (b) Discuss the isolating mechanisms that drive speciation. (7.5)