Science : Ch 09 – Heredity and Evolution

The maleness of a child is determined by the presence of the Y chromo-some in the zygote inherited from the father.

The character of the cross will be cross fertilization, which is the transfer of pollen from one plant to the stigma of fower; borne on a distinct plant of the same species.

A species is a group of organisms consisting of similar individuals which can breed Jointly and produce fertile ofspring.

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.

One of the conclusions of this theory is that the processes of genetic drift—random change in gene frequency—operate in different ways in two isolated population groups and make them more and more different from each other.

Genes are Detected on the chromosomes, which is present inside the nucleus of the cell in the crytoplasm.

The cross between RR yy and rr YY seeds will obtain RrYy ofspring which will exhibit round and yellow phenotype, as these traits are the dominant ones.

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

Some dinosaurs had feathers, although they could not fy using those feathers. Birds seem to have later adapted the feathers for fight. This means that birds are closely related to reptiles and have evolved from them