Answer:
T cells are born from hematopoietic stem cells, found in the bone marrow. Developing T cells then migrate to the thymus gland to develop (or mature). T cells derive their name from the thymus.
Explanation:
In order of importance, the world's four most important crop species are: CORN, WHEAT, RICE AND POTATOES.
Corn is the most produced grain in the world and it is used as raw material for production of different types of food. Wheat is the leading source of vegetable protein in the world, it is usually grown in dry and cold climates.
Answer:
Mendel's law of segregation
Explanation:
According to MENDEL Law of segregation, it states that allele pairs that belong to given locus segregate during the process of gamete formation and they will unite at the fertilization stage. Alleles sort out independently because the location of gene is on the specific chromosome.
Solar eclipses occur more often than lunar eclipses because in a lunar eclipse, the moon has to be perfectly aligned with both the earth and the sun.
Solar eclipses occur about 2 to 4 times per year, but the area
on the ground covered by totality is only about 50 miles wide. In any
given location on Earth, a total eclipse happens only once every hundred
years or so, though for selected locations they can occur as little as a
few years apart.
Eclipses of the Moon by the Earth's shadow occur less often than solar eclipses, however, each lunar eclipse is visible
from over half the Earth. At any given location, you can have up to
three lunar eclipses per year, but some years there may be none.
In any
one calendar year, the maximum number of eclipses is four solar and
three lunar.