Answer:
Selection is a directional process that leads to an increase or a decrease in the frequency of genes or genotypes. Selection is the process that increases the frequencies of plant resistance alleles in natural ecosystems through coevolution, and it is the process that increases the frequencies of virulence alleles in agricultural ecosystems during boom and bust cycles.
Selection occurs in response to a specific environmental factor. It is a central topic of population and evolutionary biology. The consequence of natural selection on the genetic structure and evolution of organisms is complicated. Natural selection can decrease the genetic variation in populations of organisms by selecting for or against a specific gene or gene combination (leading to directional selection). It can increase the genetic variation in populations by selecting for or against several genes or gene combinations (leading to disruptive selection or balancing selection). Natural selection might lead to speciation through the accumulation of adaptive genetic differences among reproductively isolated populations. Selection can also prevent speciation by homogenizing the population genetic structure across all locations.
Selection in plant pathology is mainly considered in the framework of gene-for-gene coevolution. Plant pathologists often think in terms of Van der Plank and his concept of "stabilizing selection" that would operate against pathogen strains with unnecessary virulence. As we will see shortly, Van der Plank used the wrong term, as he was actually referring to directional selection against unneeded virulence alleles.
Answer:
Cells have many structures inside of them called organelles. These organelles are like the organs in a human and they help the cell stay alive. Each organelle has it's own specific function to help the cell survive. The nucleus of a eukaryotic cell directs the cell's activities and stores DNA.
Explanation:
The nurse can give the following instructions:
1. the procedure will most likely last for ten minutes
2. since it is still an infant, the child will be put under anaesthesia
3. a pulsed dye laser treatment will be given
4. if general anaesthesia will be given, then there are special rules for eating and drinking restrictions before procedure
<span> </span>
CHO is the short term for carbohydrate in medical lingo.
So it would be Carbon, Hydrogen and Oxygen
A. Carbon is the answer
Answer:
Semi-conservative
Explanation:
Meselson–Stahl experiment proved that DNA replication is a semiconservative process, feeding E. colo bacteria with different types of Nitrogen isotopes (N14 and N15).
Changing the type of radioactive compound in different times of bacteria grow, they could observe that both of the isotopes were present on the bacteria culture.
Basically, if the bacteria present both of them, the DNA was replicated semiconcervely.
Guess what? they show both! (See the image for more information)
