(a) nucleus
(b) mitochondria
(c) chloroplast
(d) peroxisome
Ans: (c)
451. A married couple adopted a male child. A few years later, twin boys were born to them. The blood group of the couple
is AB positive and O negative. The blood group of the three sons is A positive, B positive, and O positive. The blood
group of the adopted son is [CSAT 2011]
(a) O positive
(b) A positive
(c) B positive
(d) Cannot be determined on the basis of the given data
Ans: (a)
452. When the bark of a tree is removed in a circular fashion all around near its base, it gradually dries up and dies because
[CSAT 2011]
(a) Water from soil cannot rise to aerial parts
(b) Roots are starved of energy
(c) Tree is infected by soil microbes
(d) Roots do not receive oxygen for respiration
Ans: (a)
648