Answer: The Magdeburg hemispheres are a pair of large copper hemispheres, with mating rims. They were used to demonstrate the power of atmospheric pressure. When the rims were sealed with grease and the air was pumped out, the sphere contained a vacuum and could not be pulled apart by teams of horses.
Explanation:
Answer: Mutation. The allelic variations that make evolution possible are generated by the process of mutation, but new mutations change gene frequencies very slowly, because mutation rates are low. Assume that the gene allele A1 mutates to allele A2 at a rate m per generation and that at a given time the frequency of A1 is p.
Explanation:
<h2>Mesophyll cells</h2>
Explanation:
The most distinctive characteristic of leaf mesophyll cells is that they are filled with many chloroplasts
Mesophyll cells constitute the main body of a leaf, occurring between upper and lower epidermis
Typically, the leaves of temperate-zone plants have two layers of mesophyll cells, the palisade mesophyll on the upper side and the spongy mesophyll on the lower side
The palisade mesophyll is a layer of densely packed, columnar cells which contain many chloroplasts, this layer is responsible for most of the photosynthesis of leaves
The spongy mesophyll is composed of large, often odd-shaped, photosynthetic cells separated from one another by large, intercellular spaces, these intercellular spaces apparently facilitate the exchange of photosynthetic gases
I think the correct answer would be the last option. Monozygotic twins are identical, while dizygotic twins are fraternal. Identical twins involves developing from one zygote where it splits, forming two embryos so that the twins would have more or less the same characteristics. This type of twins can share the same amniotic sac depending on the time the fertilized egg is divided. On the other hand, fraternal twins developed from two eggs wherein they are being fertilized by two different sperm cells resulting to twins which has different characteristics. For this type, the two fertilized eggs would develop separate amniotic sacs.
