Exchange of genetic material takes place in
Explanation: In case of sexual reproduction, two individuals contribute towards the genes of the offspring. Hence, sexual reproduction is the correct answer.
Two pink coloured flowers on crossing resulted in 1 red, 2 pink and 1 white flower progeny. The nature of the cross will be
Explanation: The term ‘cross’ in the question gives the clue for this answer.
A cross between a tall plant (TT) and short pea plant (tt) resulted in progeny that were all tall plants because
Explanation: This is a case of monohybrid cross; in which all the progenies in the F1 generation show dominant character. Hence, tallness is the dominant trait.
Which of the following statement is incorrect?
Explanation: Hormone and enzymes are proteins and formation of any particular protein is controlled by a particular gene. Hence, all other options are correct.
If a round, green seeded pea plant (RR yy) is crossed with wrinkled, yellow seeded pea plant, (rr YY) the seeds produced in F1 generation are
Explanation: Since roundness and yellow colour are shown by capital letters in the genotype so they are dominant traits. We know that only dominant traits are expressed in F1 generation.
In human males all the chromosomes are paired perfectly except one. This/these unpaired chromosome is/are
Explanation: Y-chromosome is smaller and is the only unpaired chromosome in human males.
The maleness of a child is determined by
Explanation: Y-chromosome in zygote means that the zygote would develop into a male child.
A zygote which has an X-chromosome inherited from the father will develop into a
Explanation: A zygote with XX chromosomes in the 23rd pair would develop into a girl child.
Select the incorrect statement
Explanation: Weight loss or gain happen because of external factors; especially availability of food. Genotype has no role to play in it. Hence, option ‘b’ shows incorrect statement.
New species may be formed if
Explanation: No change in the genetic material, and lack of mating cannot result in origin of new species.
Two pea plants one with round green seeds (RRyy) and another with wrinkled yellow (rrYY) seeds produce F1 progeny that have round, yellow (RrYy) seeds. When F1 plants are selfed, the F2 progeny will have new combination of characters. Choose the new combination from the following
Explanation: This can be shown by following Punette square:
A basket of vegetables contains carrot, potato, radish and tomato. Which of them represent the correct homologous structures?
Explanation: Radish and carrot are modified tap roots. Organs/parts with similar design/origin are called homologous organs.
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