The randomness in the alignment of recombined chromosomes at the metaphase plate, coupled with the crossing over events between nonsister chromatids, are responsible for much of the genetic variation in the offspring. To clarify this further, remember that the homologous chromosomes of a sexually reproducing organism are originally inherited as two separate sets, one from each parent. Using humans as an example, one set of 23 chromosomes is present in the egg donated by the mother. The father provides the other set of 23 chromosomes in the sperm that fertilizes the egg. Every cell of the multicellular offspring has copies of the original two sets of homologous chromosomes. In prophase I of meiosis, the homologous chromosomes form the tetrads. In metaphase I, these pairs line up at the midway point between the two poles of the cell to form the metaphase plate. Because there is an equal chance that a microtubule fiber will encounter a maternally or paternally inherited chromosome, the arrangement of the tetrads at the metaphase plate is random. Thus, any maternally inherited chromosome may face either pole. Likewise, any paternally inherited chromosome may also face either pole. The orientation of each tetrad is independent of the orientation of the other 22 tetrads.
Explanation:
the is a definite article meaning that you cannot use it
"an" can only be used before words beginning with vowels
therefore the answer is" a"
The process of microsporogenesis
The clavicle or the collar bones are the only long bones in the body that lie horizontally. Calling the clavicle as the beauty bone is basedon the reason that it helps frame the face and round out the imperfection of your jaw line.
Yes, I think the cell theory is a scientific theory because its statements are testable and verifiable.
<h3>What is a scientific theory?</h3>
A scientific theory is a well-sustained statement based on different types of scientific evidence.
A scientific theory must be testable, which means that it can be confirmed or rejected by using the scientific method.
In conclusion, the cell theory meets the definition of a scientific theory because it is testable and verifiable.
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