Gene mutations that involve changes in one or a few nucleotides and occur at a single point in the DNA sequence; This type of mutation includes substitutions, insertions, and deletions; This mutation usually occurs during replication; If a gene in one cell is altered, the alteration can be passed on to every cell that …

A nonsense mutation is also a change in one DNA base pair. Instead of substituting one amino acid for another, however, the altered DNA sequence prematurely signals the cell to stop building a protein. This type of mutation results in a shortened protein that may function improperly or not at all.

The correct answer is (c) substitution. A substitution mutation occurs when one nucleotide is exchanged for another in the DNA sequence.

A mutation may change a trait in a way that may even be helpful, such as enabling an organism to better adapt to its environment. The simplest mutation is a point mutation. This occurs when one nucleotide base is substituted for another in a DNA sequence. The change can cause the wrong amino acid to be produced.

In fact, the G-T mutation is the single most common mutation in human DNA. It occurs about once in every 10,000 to 100,000 base pairs — which doesn’t sound like a lot, until you consider that the human genome contains 3 billion base pairs.

Gene flow is the movement of genes from one population to another population. Examples of this include a bee carrying pollen from one flower population to another, or a caribou from one herd mating with members of another herd.

Alternatively, gene flow can take place between two different species through horizontal gene transfer (HGT, also known as lateral gene transfer), such as gene transfer from bacteria or viruses to a higher organism, or gene transfer from an endosymbiont to the host.

gene migration

Gene flow is also called gene migration. Gene flow is the transfer of genetic material from one population to another. Gene flow can take place between two populations of the same species through migration, and is mediated by reproduction and vertical gene transfer from parent to offspring.

When gene flow is blocked by physical barriers, this results in Allopatric speciation or a geographical isolation that does not allow populations of the same species to exchange genetic material.

Gene flow is the movement of genes into or out of a population. Such movement may be due to migration of individual organisms that reproduce in their new populations, or to the movement of gametes (e.g., as a consequence of pollen transfer among plants).

There are two major types of genetic drift: population bottlenecks and the founder effect. A population bottleneck is when a population’s size becomes very small very quickly. This is usually due to a catastrophic environmental event, hunting a species to near extinction, or habitat destruction.

Genetic drift describes random fluctuations in the numbers of gene variants in a population. Genetic drift takes place when the occurrence of variant forms of a gene, called alleles, increases and decreases by chance over time. These variations in the presence of alleles are measured as changes in allele frequencies.

Genetic drift can be caused by a number of chance phenomena, such as differential number of offspring left by different members of a population so that certain genes increase or decrease in number over generations independent of selection, sudden immigration or emigration of individuals in a population changing gene …

Genetic drift can result in the loss of rare alleles, and can decrease the size of the gene pool. Genetic drift can also cause a new population to be genetically distinct from its original population, which has led to the hypothesis that genetic drift plays a role in the evolution of new species.

As genetic drift increases, population size decreases. When a population is founded by a small number of individuals, it is likely that chance alone (genetic drift) will cause the allele frequencies in the new population to be different from the source populations.

Small populations tend to lose genetic diversity more quickly than large populations due to stochastic sampling error (i.e., genetic drift). This is because some versions of a gene can be lost due to random chance, and this is more likely to occur when populations are small.

The most obvious factor affecting the rate of genetic drift is the size of the population. If the population is small, then a small sample is taken of the gametic population in every generation.

A mutation is a change in an organism’s DNA. Mutations may instantly introduce a new allele into a population, causing small but intermediate shifts in allele and genotype frequencies. Because mutations are the ultimate source of all genetic variation, they collectively are extremely powerful in influencing evolution.

Five forces can cause genetic variation and evolution in a population: mutations, natural selection, genetic drift, genetic hitchhiking, and gene flow.

There are two general classes of evolutionary change: microevolution and macroevolution. Microevolutionary processes are changes in allele frequencies in a population over time. Three main mechanisms cause allele frequency change: natural selection, genetic drift, and gene flow.