<em>It is True that when making a Punnett square the alleles of the mother and father are written at the top and side of the four square box. </em>
Answer AND Explanation:
<u>FACTORS THAT CAUSE GENETIC VARIATIONS</u>
- Crossing over. At the chiasmata during prophase I of meiosis, breakage may occur and exchange of genetic information may take place. New gene combinations which result in variations.
- Independent assortment. The arrangement of homologous chromosomes at the equator of the spindle during metaphase of the first meiotic division is random. These homologous chromosomes segregate into different daughter cells which contain different genetic combinations which brings about variation
- Fertilisation permits parental genes to be brought together in different combinations. This is the cause of variations in members of the same family.
- Mutation is the spontaneous change in the genetic makeup of an organism. These changes may be inherited by the offspring therefore beginning variation.
<span> 4th planet from the Sun, which is a perfect distance to utilize the Sun's energy
</span>
Within any ecosystem, there is a fixed amount of energy available for
organisms to use. since organisms usually produce more offspring than a
given
ecosystem can support, this causes competition. They compete over who will be the dominant one and who will be left to die.