The answer for the question is Migraine<span>. Migraines Headaches are extremely, nearly paralyzing headaches that are located on one side of the head and are sometimes accompanied by dizziness, nausea, or vomiting. They normally develop in two phases; The first phase, in which blood vessels in the brain narrow (vasocontsriction), such that the flow of blood to arts of the brain is reduced. Second phase; occurs when the blood vessels expand, such that blood flows through them rapidly, thus stimulating many neuron endings and causing pain. </span>
Answer:
Which type of selection tends to increase genetic variation? A. Disruptive selection B. Directional selection C. Stabilizing selection
The Answer is option A (Disruptive selection)
Explanation:
Selection can either shift the mean value of a trait, reduce the trait's variation, or increase its variation.
Genetic variation which allows natural selection to increase or decrease frequency of alleles already in the population is a source of phenotypic variation as it refers to differences in all the hereditary information of members of the same species.
Disruptive Selection is important in maintaining variation and initiating speciation as it Increases Variation by favoring alleles corresponding to more extreme phenotypes. But for it to occur, the mean phenotype has to experience the lowest fitness. Disruptive selection affects the frequency distributions of alleles and genotypes within a population.
Disruptive selection is based on the variance of a trait in a population as it increases genetic variance by equalizing the frequencies of existing alleles at polymorphic loci (a genetic loci with two or more alleles). Disruptive selection maintains and may even increase variation in natural populations by favoring extreme phenotypes, individuals with extreme values for a trait have greater reproductive success than individuals with intermediate values.
10 pounds
10% of energy moves on through each trophic level so if a chicken ate 10 pounds of a producer that would be equivalent to the fox eating 1 pound of chicken. (10 times .1 = 1)
Answer:
A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals
called mutagens, or infection by viruses. Germ line mutations occur in the eggs and sperm and can be passed on to offspring, while somatic mutations occur in body cells and are not passed on.
Mutation has been the source of many Hollywood movies, but it's really a simple process of a mistake made in a DNA sequence as it's being copied. Some of that's just the background noise that DNA copying is not perfect, and we should be glad of that or evolution couldn't operate. But mutation can also be induced by things like radiation or carcinogens in a way that can increase the risk of cancers or birth defects. But it's pretty simple; it's basically an induced misspelling of the DNA sequence.
That's a mutation.
When a variant alters a protein that plays a critical role in the body, it can disrupt normal development or cause a health condition. A condition caused by variants in one or more genes is called a genetic disorder. In some cases, gene variants are so severe that they prevent an embryo from surviving until birth.
The Bering Strait separates Siberia and Alaska.