Answer:
In animal field studies, why do scientists usually try to work without making the animals aware that the humans are present? It is necessary to observe the animals without disturbing them. When a controlled experiment is not possible, why do scientists try to identify as many relevant variables as possible?
Answer:
0.095
Explanation:
Phenylkentonuria is a disease caused by a recessive allele.
The frequency of the recessive allele + the frequency of the dominant allele equals 1.
The frequency of the recessive allele is q = 0.05
The frequency of the dominant allele then is p = 1 - q = 0.95
If people mate randomly, the frequency of the homozygous dominant genotype will be p², the frequency of the heterozygous genotype will be 2pq and the frequency of the homozygous recessive genotype will be q² .
2pq=2× 0.05 × 0.95
2pq=0.095
The heterozygote frequency in the population is 0.095
Answer:But Earth's distance from the sun doesn't change enough to cause seasonal differences. Instead, our seasons change because Earth tilts on its axis, and the angle of tilt causes the Northern and Southern Hemispheres to trade places throughout the year in receiving the sun's light and warmth most directly.Sep 23, 2019
Explanation:
Typhoid fever is most common in non-industrialized countries. Travelers to Asia, Africa, Eastern Europe, and Latin America are especially at risk. Salmonella typhi bacteria are shed in the urine or stool of infected persons, including chronic carriers. There are no known animal reservoirs for typhoid fever.