I) Locus- the chromosomal site where a specific gene is located. A locus is a fixed position on a chromosome, like the position of a gene or a marker. Each chromosome carries ,many genes; human's estimated haploid (n) protein coding genes are about 20,000, on the 23 different chromosomes.
ii) Interference; the observed double crossover frequency differs from the expected double crossover frequency. Cross over interference is used to refer to the non-random placement of crossovers with respect to each other during meiosis. It results in widely spaced crossovers along chromosomes. Interference may exert its effect across whole chromosomes. As chromosomes in many eukaryotes are large, interference must be able to act over megabase lengths of DNA.
iii) Linkage- the tendency for genes located in close proximity on the same chromosome to be inherited together. Normally when two genes are close together on the same chromosome, they do not assort independently and are said to be linked. Whereas genes located on different chromosomes assort independently and have a recombination frequency of 50%, linked genes have a recombination frequency that is less than 50%.
iv) Recombination- the process by which a new pattern of alleles on a chromosome is generated. Genetic recombination is the production of offspring with combinations f traits that differ from those found in either parent. During meiosis in eukaryotes, genetic recombination involves the pairing of homologous chromosomes. This may be followed by information transfer between the chromosomes.
The most common way these trees undergo pollination is through seeds and pollen.
The pollination is done with help of wind and birds where pollen transform from one plant to another.
<u>Explanation:</u>
The plants that undergoes pollination process through the seeds that are present in it are called as Angiosperms. These contains fruits. The seeds are usually present inside these fruits. Flowering plants are also called as Angiosperms.
These fruits and flowers are absent in gymnosperm. Even then they contain seeds inside the leaves surface. They will undergo pollination with these naked seeds. It is the fruits, flowers and the endosperm that are present in the seeds that help us to find difference between these two. The only common thing that exists between these two are seeds and pollen with which they pollinate.
In gymnosperms, pollen is transferred from male cone to female cone through wind or birds. Now, the pollen is germinated into pollen tubes and sperm for egg fertilization.
