(1)

Dominant allele can express even in the presence of a recessive allele. Hence dominant phenotype is more common. Round seeds are dominant over wrinkled seeds; hence would be more abundant.

(3)

In the $F₂$ generation, the ratio of pure tall plants to pure short plants will be 1:1. The other two plants that are produced will be tall as well, but will not be pure.

(2)

The new combination in $F₂$ progeny will be round yellow and wrinkled green. The phenotypic ratio obtained in a dihybrid cross is 9:3:3:1.
The phenotypic ratio will be – Round Yellow: Round green: Wrinkled yellow: Wrinkled green = 9:3:3:1

(1)

In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females. Females have two copies of the X chromosome, while males have one X and one Y chromosome.

(1)

In the human zygote, the number of pairs of autosomes and sex chromosomes is the same as in an adult human. A human adult possesses 23 pairs of chromosomes, 22 of which are autosomes and 1 of which is a sex chromosome.

(3)

In human males, one pair called as the sex chromosomes are unpaired. Here, one is a normal sized X chromosome while the other is a short Y chromosome. Women have a perfect pair of sex chromosomes, both called as X. Whereas in males the X and Y chromosomes are not paired well.

(1)

Autosomes do not play any role in the determination of the sex of an individual since they are alike in both the males and the females and are 22 in pairs.

(1)

On different copies of the same chromosome, different alleles are present. One chromosome is inherited from the father via the male gamete, while the other chromosome is inherited from the mother via the female gamete. After fertilisation, a zygote with 23 pairs of chromosomes is created, with alleles for a trait present on the homologous pair.

(4)

The X and Y chromosomes are found in humans and most other mammals. Males have both X and Y chromosomes in their cells, whereas females have two X chromosomes. X chromosomes are found in all egg cells, while X or Y chromosomes are found in sperm cells.

(2)

Big nose is an inherited trait which can be passed from parents to offspring.

(3)

Environmental factors influence the development of acquired traits. It is because the availability of less or more food can modify the size of the body, it is an acquired feature. The other three—eye and skin colour, and nature of hair, are inherited characteristics from the parents.

(4)

Variation is the difference between individuals within a population. These arise between the progeny and parents/ancestors and form a backbone for natural selection to act on.

(1)

Genetics is the branch of biology that deals with questions of inheritance. It uses techniques from various disciplines like Molecular biology, Cell biology, and many more to understand the basis of inheritance.

(3)

Any difference between cells, individuals, or groups of organisms of any species produced by genetic differences (genotypic variation) or the effect of environmental conditions on the manifestation of genetic potentials is referred to as variation (phenotypic variation).

(4)

Genes can acquire mutations. A gene mutation is a change in the DNA sequence that makes up a gene that is permanent and differs from the sequence found in most people.

(3)

The process of crossing pollen from one flower to the pistils of another flower is known as cross-pollination. When a new plant is formed as a result of cross-pollination from different varieties of a plant, the newly formed plant is called hybrid plant.

(4)

Variation in gene frequencies is referred to as genetic variation. Eye colour is determined by variations in genes of a person. Two children having different eye colour is an example of genetic variation.

(4)

Here, all the statements are correct. Hence, the answer will be option [D].

(2)

Mendel discovered the laws of inheritance. He attributed these traits being encoded by factors. Later studies showed that these factors are genes.

(2)

Characteristics from parents are passed down to offspring during sexual reproduction. These are the combinations of female and male parent. This is known as heredity.

(1)

The term “phenotype” refers to an organism’s observable physical properties, such as its appearance, development, and behaviour.

(4)

Characters or traits are the characteristics that a person expresses and can be seen in their phenotype. Height, eye colour, and body colour are all controlled by genes and can be inherited.

(3)

The cross described in the question is a typical Mendelian genetic cross showing incomplete dominance, where the offspring display a 1:2:1 phenotypic ratio (1 red, 2 pink, 1 white). Among the given options, "Cross fertilisation" (This involves the fertilisation of an organism with the gametes from another organism. It typically refers to the process between two different plants, not necessarily describing the specific genetic inheritance pattern observed) is the most applicable.

(1)

Mendel’s law of dominance states that in a heterozygote, one trait will conceal the presence of another trait for the same characteristic. Rather than both alleles contributing to a phenotype, the dominant allele will be expressed exclusively. The recessive allele will remain “latent,” but will be transmitted to offspring by the same manner in which the dominant allele is transmitted. The recessive trait will only be expressed by offspring that have two copies of this allele.

(4)

This represents a parent that is heterozygous for both tallness and violet flower color. This genotype allows for the possibility of both tall and short offspring as well as violet and white flowers. However, since all progeny were violet, the white allele seems to have no effect in this cross, suggesting that the other parent must carry the recessive allele for white flowers.

(1)

When two traits of a character are crossed, the $F₁$ plants only show one of the two traits, which is known as the dominant trait. The recessive trait (dwarfness) is a trait that does not manifest itself in the $F₁$ generation

(1)

Recessive traits are the ones that require both alleles to be present to result in the expression of the gene product. Of the mentioned traits, only dwarf stem height is a recessive trait.