Crossing over occurs at the four-strand stage when two homologous chromosomes, each consisting of a pair of sister chromatids, are paired. Each crossover involves just two of the four strands and generates two recombinant strands.
Hope this helps!
D surface tension because, adhesion is sticking, b makes no sense for this question, and heat has nothing to do with it either, because it distributes it's weight throughout its legs so it doesn't sink (it doesn't weigh much so this works.)
Hope this helps don't forget to hit that heart :)
Answer:
a. Stabilizing selection
Explanation:
Babies lower than 5.5lbs would suffer from various disorder because of low birth weight as their body would not be able to compete as well they would have weak immune system and malnourishment. Whereas high birth weight carry the equally above risk as their body wont be able to cope up and organs become insensitive to various hormones. for the survival the birth weight should be within a median range so that it would be favorable for themselves and surroundings.
Stabilizing selection occurs when a population stabilizes on a particular trait value and genetic diversity decreases. As in this example, an average baby weight has to favour against extreme variation for it's better survival.
therefore, this is an example of stabilizing selection.
Answer:
D.20,000
Explanation:
The Gross Annual Primary Productivity for the wetland ecosystem is the amount of carbon taken up by the aquatic producers through photosynthesis.
Given that: Net Annual Primary Producer is 8,000 kcal/m2 per year, and respiration by the aquatic producers is 12,000 kcal/m2 per year, using the formula NPP = GPP – Respiration, we can determine the Gross Annual Primary Productivity of the wetland ecosystem.
NNP = 8,000 kcal/m2
Respiration = 12,000 kcal/m2
GPP = x
8,000 = x – 12,000 (NPP = GPP – Respiration)
Solve for x:
x = 8,000 + 12,000
x = 20,000 kcal/m2 per year
GPP = 20,000 kcal/m2 per year
