Science : Ch 09 – Heredity and Evolution

Acquired traits are the changes which do not occur in the DNA of the individual or in its genes thus they are not passed from one generation.

Radish and carrot represent the correct homologous structures because both have similar design or structure, though both are of different species.

The size of the body is an acquired trait because it depends on nutritional status, health conditions, etc. It can change depending on the Components like availability of less or more food.

One pair called the sex chromosomes is odd, not always being a perfect pair. Women have a perfect pair mismatched pair, in which one is a normal-sized X while the other is a short one called Y (XY).

The two versions of a trait which are brought in by the male and female gametes are situated on copies of the same chromosome. Each parent contributes one copy of the gene for a particular trait.

The wings of an insect and a bird have distinct structures but they carry out the same function of fying. Therefore, they are analogous organs

Asexual reproduction will not result in variation as there are no gametes involved. Movement of individuals from one habitat to another will not afect the DNA.

If we dig into the earth and start fnding fossils, the fossils we fnd closer to the surface are more contemporary than the fossils we fnd in deeper layers.

The sex of the children will be determined by what they inherit from their father. A child who inherits an X chromosome from her father will be a girl and the one who inherits a Y chromosome from him will be a boy

The tendril of a pea plant and the phylloclade of Opuntia are homologous structures, as they are modifed stems but serve diferent functions in diferent plants.

The genotype ratio of F2 generation is: TT : Tt : tt = 1 : 2 : 1. Therefore, the ratio of TT and tt plants of F2 generation will be the same. 4. Two pink coloured fowers on crossing resulted