<span>As humans cause more carbon dioxide to be released into the Earth's atmosphere, it causes the oceans to become much more acidified which in turn begins to damage the precious coral reefs. Roughly one quarter of all the life in the ocean is dependent on coral reefs for food and shelter.</span>
Answer:
Niacin (Ans. A)
Explanation:
Nicotinamide adenine dinucleotide (NAD) is known as important cofactor which help in carrying electrons from one reaction to another reaction in the cellular respiration process.
Cells are able to restore performed compounds which are containing a pyrimidine base precursor vitamin for the synthesis of NAD: nicotinamide, nicotinic acid, and nicotinamide riboside.
These elements are taken up from the diet whos containing vitamin B3. Nicotinamide, and nicotinamide riboside both can be absorbed from the gut. Niacin or vitamin B3 also produced within cells with the help of cellular digestion of NAD+.
when a homozygous white rabbit (bb) is crossed with a heterozygous black rabbit (Bb). what proportion of white rabbits would the offspring have?
Answer:
Based on the Mendelian fashion cross,
bb is hetezygote reccessive.(white)
Bb is heterozyote dominant.(black)
Therefore,the the cross to show the proportion is below
Bb,Bb,bb,bb,
2 blacks(hetero zygote blacks) and 2 white.(homo zygote whites)
thus 2 of the offspring will be white, in 50%, of the number of offspring
Explanation:
DNA methylation is a process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription.
The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
