It consists of the following six muscles: Piriformis, gemellus superior, obturator internus, gemellus inferior, quadratus femoris and the obturator externus.
Answer:
1. a.mutation,
b. recombination,
c. immigration of genes,
d.climate and
e.associations
2. Mutation : Is the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes.
- Gene flow : 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.
- Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
- Genetic Recombination : Is a process by which pieces of DNA are broken and recombined to produce new combinations of alleles. This recombination process creates genetic diversity at the level of genes that reflects differences in the DNA sequences of different organisms.
3. The 3 Types of Natural Selection
- Stabilizing Selection.
- Directional Selection.
- Disruptive Selection.
- Stabilizing selection : Stabilizing selection is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value. This is thought to be the most common mechanism of action for natural selection because most traits do not appear to change drastically over time.
- Directional Selection: In population genetics, directional selection, is a mode of negative natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype.
- Disruptive selection : Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.
There are two types of polar climate: ET, or tundra climate; and EF, or ice cap climate. A tundra climate is characterized by having at least one month whose average temperature is above 0 °C (32 °F), while an ice cap climate has no months above 0 °C (32 °F).
What I did was I said the plates moved 3 centimeters per year and and times it by 100 million years and you get how far the plates have moved against each other. When they move that far against each other, the land would break and pile up to create mountains. Under the sea, the earth would collide and and create a chain of volcanoes. I got a 4/4 for this question, hope this helps you. Good luck!
Answer:
A forest ecosystem can support a limited number of bears because bears are the supreme predators of their ecosystem and very few animals can hunt bears so nature by supporting a limited number of bear populations supports a balanced number of population of its prey like insects, fishes, deer.
Another reason for the limited population of bear is that bear occupies the highest trophic level in the ecosystem so according to 10% law of energy transfer, it will get very less energy from its food so it needs to eat more.
Therefore the population of bears is limited because the environment can not meet the energy requirement of many bears so a forest ecosystem can support a limited number of bears.
