(d) gravity
Ans: (c)
411. The corn in an underground stem that grows
      (a) horizontally
      (b) vertically
      (c) above the soil
      (d) obliquely
Ans: (b)
412. The potato is a modified stem, is explained by the presence of
      (a) Branches
      (b) Leaves
      (c) Buds
      (d) Scale leaves and auxiliary buds
Ans: (d)
413. Temperature treatment which shortens the vegetative period and hastens the flowering is called
      (a) Phototropism
      (b) Photoperiodism
      (c) Vernalisation
      (d) Thermoregulation
Ans: (c)
414. Rate of mutation can be increased in plants by
      (a) More manure
      (b) More pesticides
      (c) X-ray
      (d) More light
Ans: (c)
415. In phototropism, auxins
      (a) Promote growth of cells
      (b) Inhibit cell division
      (c) Inhibit growth of cells
      (d) Stimulate differential growth of cells
Ans: (a)
416. What is "atavism"?
      (a) The genes which show numerous phenolypic effects
      (b) Reappearance of traits after several generations
      (c) Effects of mutation
      (d) Intermediate inheritance of genes
Ans: (b)
417. Genes are arranged in chromosomes
      (a) In clusters
      (b) In binary fashion
      (c) In linear fashion
      (d) Scattered
Ans: (c)
418. Sex linked genes are carried by
      (a) X-chromosomes
      (b) Y-chromosomes
      (c) different part of X- and Y-chromosomes
      (d) autosomes
Ans: (c)
419. The equilibrium and co-ordination is looked after by which part of the brain?
      (a) Cerebrum
      (b) Medulla oblongata
      (c) Cerebellum
      (d) Olfactory lobes
Ans: (c)
420. The involuntary muscles are controlled by the
      (a) Cerebrum
      (b) Cerebellum
      (c) Medulla oblongata
      (d) Pons