Answer: Because two or more daughter cells will be formed, and each must have the parent chromosome in itself
Explanation:
Cell undergo cell division (mitosis or meiosis) as part of healthy development of a living organism. Before division, the cell during the resting phase( Interphase) makes two copies of all its organelles including nucleus, as it would form two daughter cells (in mitosis) or four daughter cells (in meiosis)
The answer is True. Hope this helps.
Option D – amphibians may use their skin for gas exchange is the characteristic feature of amphibians that differs from reptiles.
Explanation:
The amphibian skin is moist, thin and marbled and supplied by blood vessels running on its surface. The moisture present in the skin dissolves the oxygen present in its surrounding which is absorbed by the blood vessels. Special glands help the amphibians to keep the skin moist.
The very thick and tough scales present on the reptiles prevent them to absorb oxygen through their skin. Hence, they breathe and respire through their lungs.
Amphibians have three-chambered heart. They do not develop amniotic eggs. Adult amphibians although spend much time on land, they breed only in water due to the absence of amniotic sac
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The gene p53, also called the guardian of the genome is located on the 17th chromosome in human genomes.
It was given this alternative name because it has a role in response to damage of DNA molecule and in preventing cancer.
The protein product of this gene stops the replication of damaged DNA, activates proteins that repair the DNA damage and if the reparation proteins fail to fix the damage it activates the process of apoptosis or so-called cell death in order to prevent the damaged cell to proliferate and potentially develop into a tumor.
For centuries scientists thought the Universe always existed in a largely unchanged form, run like clockwork thanks to the laws of physics. But a Belgian priest and scientist called George Lemaitre put forward another idea. In 1927, he proposed that the Universe began as a large, pregnant and primeval atom, exploding and sending out the smaller atoms that we see today.
His idea went largely unnoticed. But in 1929 astronomer Edwin Hubble discovered that the Universe isn’t static but is in fact expanding. If so, some scientists reasoned that if you rewound the Universe's life then at some point it should have existed as a tiny, dense point. Critics dismissed this: the celebrated astronomer Fred Hoyle sarcastically called this concept the “Big Bang Theory"
