Answer: Option B. -> False
:
B
A woman is not responsible for the gender of her child. In humans, sex determination is of XX-XY type, i.e XX is female and XY is male.Awoman can produce eggs of only one type (containing X sex chromosome) whereas amale can produce both thetypes of sperms (containing either X or Y sex chromosome). The genderof the baby depends on which type of sperm fuses with the egg. If Y-containing sperm fuses with eggthen the resulting baby will have XY combination and will be male. Similarly, if X containing sperm fuses with the egg, the resulting baby will have XX combination and will be female. Thus, theman is responsible for the gender of the child.

Answer: Option B. -> False
:
B
Recessive traits do not get expressed in an individual until and unless they are present in homozygous condition. A dominant trait only can express itself in any condition i.e. homozygous or heterozygous.

Answer: Option D. -> Fossils
:
D
The preserved traces of living organisms like plants, animals, insects from remote pastare known as fossils. Study of fossils is known as paleontology. Fossils are studied to understand the process of evolution and to establishevolutionaryrelationships.

Answer: Option B. -> outcome
:
B
Natural selection is the phenomenon wherein nature selects organisms having traits favourable to the environment. The organisms exhibit different characteristics due to different genotypes (variation). If these characteristics are favoured by the natural environment, the organisms with these variations survive and propagate, and may form different species. Thus, evolution is the outcome of natural selection.

Answer: Option A. -> Only 1 is correct
:
A
The first statement is correct as half of the genetic information of any individual comes from either of the parents. But, the second statement is incorrect as environment plays a role in determining the phenotype of the person. Both the genetic and environmentalfactors together determine the phenotypic expression of a gene in an individual.

Answer: Option C. -> Both 1 and 2 are true
:
C
Evolution is the process by which lot of diverse organisms are formed from earlier organisms over a span of millions of years. Humans are simply one more species in this spectrum of evolution of life on earth. We are not the last and ultimate of evolution. There could be more in evolution that can happen. All other organisms have their own status in evolution as well.

Answer: Option A. -> True
:
A
Genetic variation is a measure of the genetic differences that exist within a population. It is the basic phenomenon on which environmental forces act to create evolution among populations.

Answer: Option B. -> variation
:
B
Variation is the degree of differences in the progeny and between the progeny and the parent. Variations can be seen either in the morphological appearance (phenotype) or the genetic makeup (genotype) of an organism.

Answer: Option B. -> XY
:
B
Humans contain 22 pairs of autosomes and 1 pair of sex chromosomes. The female gamete or the egg consists of an “X” chromosome. If this is fertilised by a sperm containing “X” chromosome, the baby will have “XX” chromosome and will be a female. But if the egg is fertilised by a sperm containing “Y” chromosome, the baby will have “XY” chromosome and will be a male.

Answer: Option B. -> Natural selection
:
B
When a population of a particular variant organism increases due to a survival advantage, it is the natural selection. In this case, green beetles cannot be seen by the crow and therefore, their population has grown compared to the red coloured beetles. Thus, natural selection pressure is exerted by crows.