1) 6-bacteria reproduce by…… a) Budding b) Sporogony c) Regeneration d) Binnary fission 2) 7-the energy source for all stars…… a) Nuclear reaction b) Chemical reaction c) Burning gases d) moving stars 3) 8-within minutes after big bang helium gas was formed by  a) 75% b) 55% c) 65% d) 25% 4) 9-the sun was born after about …..million years from the Big Bang a) 3000 b) 2000 c) 10000 d) 15000 5) 10-…….is used to correct the short sightedness a) Convex lense b) Convex mirror c) Concave lense d) Concave mirror 6) 23pairs of choromosomes containing a) Chromatides b) Centromere 7) 5-tetrad consists of ……..chromosom a) 2 b) 4 c) 6 d) 8 8) 4-……are not divided at all a) Skin cells b) Liver cells c) Nervecells d) Stomach cells 9) 3- if the chromosomal number in male gamete of an organism is 20 so the 3- if the chromosomal number in male gamete of an organism is 20 so the chromosomal number in liver cell equals…..  a) 5 b) 10 c) 20 d) 40 10) 2-the number of chromosomes in pollen grains is …….the number of chromosomes in female ovum a) Half b) Double c) Equal to d) Quarter 11) 13-if the focal length of a concave mirror is 5cm so its diameterequals......  a) 5cm b) 10cm c) 15cm d) 20cm 12) 12-the parental individual disappears in case of reproduction in……… a) Yest b) Starfish c) Hydra d) Amoeba 13) 11-the changes that occur in the ……of mitotic division are called adverse changes a) Interphase b) Prophase c) Telophase 14) The real image is always a) Smaller b) Inverted c) Upright d) Magnefied 15) 15-crossing over phenomenon happens in………. a) Telophase b) Anaphase c) Metaphase d) Prophase  16) 17-the focal length of spherical mirror is ………. a) Equal b) Half c) Quarter d) Double 17) 16-chromosomes are found in the……. a) Vacuole b) .Mitochondria c) Nucleus d) Green plastids 

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