Answer:. Nondisjunction during meiosis I in either the male and female gamete
The failure of homologous chromosome to separate at mitosis, or failure of sister chromatids to separate at Anaphase of meiosis I or ii is called non-disjunction.
In this cell division anomaly the unsegregated chromosomes are separated into cells as single chromosomes, therefore extra copies are therefore inherited.This result is one of the cell having an extra copies of chromosomes than others( chromosomes 21.
If this extra chromosome copies is segregated into a sperm or egg, the resulting zygote cells will have extra copy as chromosome 21, and hence Down syndrome.
→It is more common in Meiosis 1 than ii,because of longer duration of the first stage of division than meiosis ii,given rooms to errors.
→Most common in women(with age increase) than men because of exchange of telomeres in them,which worsen with age. Their Meiotic mechanism which weaken with age, and more prone to errors compare to men,
Explanation:
Answer: They evolve through genetic drift.
Explanation: <u>Junk DNA refers to noncoding sections of a genome</u>. It consists of repeated segments scattered randomly throughout the genome generated through transposition or movement of sections of DNA to different positions in the genome.
Genetic drift is the change in the frequency of an allele in a population due to random sampling of organisms. This process is caused by spontaneous mutations and may cause the alleles to disappear completely and thereby reduce genetic variation. <u>Many of these genetic alterations are in regions of "junk DNA"</u>
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Answer: geno 50% 50%
Pheno: 50% chocolate 50% black
Explanation: the punnett square should have 2 capital L's across the top and down the side one capital L and one lower case L. The firs box should be LL the second box should be LL the third box should be Ll and the fourth should be Ll
Answer:
Do you have a picture of the map? If not i can't answer the question.
Explanation:
Answer:
carbon monoxide, nitrogen oxides