The Nucleus is separated from the cell’s cytoplasm by a
membrane. The nucleus contains hereditary materials made of plenty proteins and
DNA. The nucleus directs all cell activities. Nucleus is commonly found in
Eukaryotic cells. The genetic materials found in the Nucleus is organized as
DNA molecules, together with a wide array of proteins, which causes to form
chromosomes.
Answer:
The living organisms in an ecosystem can be divided into three categories: producers, consumers and decomposers. They are all important parts of an ecosystem. Producers are the green plants. They make their own food.
Explanation:
Answer:
Domestic dogs, cheetahs, alpine plants
Explanation:
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:
The answer is (D), because none of the other answers make sense