The longitudinal halves of a chromosome that has undergone replication are known as chromatids. They will not be called chromosomes until after they are separated during Mitosis. Mitosis distribute the chromatids to daughter cells as a cell divides. The chromosomes are initially replicated in cells undergoing Meiosis, as in preparation for the mitotic division, but then, these chromosomes are divided twice so that four daughter nuclei are produced, each having the haploid chromosome number.
Distribution of phenotypes within a population may be impacted by different types of natural selection. These types of selection include;
Directional selection involves a change in the environment shifts of phenotypes observed. Example is the giraffe neck-length, where the length got longer and longer over time to reach the leaves at the top of trees.
Stabilizing selection , this is a selection where an average phenotype is favored. example is number of eggs laid by birds such that too many eggs will be a waste of energy because some chicks would starve.
Disruptive selection is a selection where individuals with an average value of a trait are affected most while those with values below average are affected least. Example small individuals are capable of hiding from predators while big individuals can not fit in the hiding place but instead will fight with predators.
Answer:
B) Hydrogen Bond
Explanation:
Those are the bonds that the restrictive enzymes unzip and the bonds that hold the complementary bases.
The right answers are:
A-present in eukaryotic genomes ==> Both exons and introns
B-generally absent from bacterial genomes ==> Introns
C-part of the final mRNA strand ==> Exons
D-code for an amino acid sequence ==> Exons
E-removed from initial mRNA strand prior to translation ==> Introns
F-present in the DNA used as the template for transcription ==> Both exons and introns
In the genes of eukaryotic organisms, the exons are the segments of an RNA precursor that are conserved in the RNA after splicing and that are found in mature RNA in the cytoplasm. The segments of the RNA precursor that are removed during splicing are called in opposition to introns. Exons are mainly found in messenger RNAs (mRNAs) encoding proteins. Some mRNAs may sometimes undergo an alternative splicing process in which one or more exons may be excised or some introns preserved in rare cases.