Answer:
Alpine tundra areas are found only at high elevations.
Explanation:
The arctic tundra is a specific region that covers the northernmost parts of the world from the north pole and extending south, whereas alpine tundra are found across the world at high altitudes.
Answer:
D. Population genetics
Population genetics is the study of genetic variation within populations, and involves the examination and modelling of changes in the frequencies of genes and alleles in populations over space and time. ... In natural populations, however, the genetic composition of a population's gene pool may change over time.
Explanation:
microevolution - evolutionary change within a species or small group of organisms, especially over a short period. (Not studying the overall evolution in the population, just a single allele usually) Not it then
macroevolution - Macroevolution in the modern sense is evolution that is guided by selection among interspecific variation, as opposed to selection among intraspecific variation in microevolution (this goes over huge groups of different species) Not it then
gene pool - The gene pool is the set of all genes, or genetic information, in any population, usually of a particular species. (Not the study of evolution in a population) Not that then
So it has to be D
The pyloric sphincter is compose of smooth muscle and is located between the pylorus in the stomach and duodenum of the small intestine. In digestion, it serves as a valve controlling the flow of food thus it prevents the contents of small intestine backing up into the stomach.
