Answer:
Single-cell organisms
Explanation:
In 1735, Linnaeus introduced a classification system with only two kingdoms: animals and plants. Linnaeus published this system for naming, ranking, and classifying organisms in the book "Systema Naturae". In the epoch that Linnaeus created this system, single-cell organisms such as bacteria and protists were almost unknown. In 1866, E. Haeckel added a category including both bacteria and protozoa, thereby adding a category formed by single-cell organisms (different from animals and plants). During the 1900-1920 period, bacteria were classified as a separated kingdom named 'prokaryotes'. The current three-domain classification system was introduced by C. Woese in 1990. In this system, all forms of life are divided into three different domains: archaea, bacteria, and eukaryote domains (this last composed of protists, fungi, plants and animals).
Answer:
Explanation: When this study was carried out by Meselson and Stahl, their findings are compatible with the trend expected by semi-conservative analysis, establishing this as the right template. The two parent strands are split as DNA replicates, and each strand acts as a blueprint for a new DNA strand synthesis.
After the first replication, there are two DNA double helices each marked as superscript 14 N slash superscript 15 N. After the second replication, four double helices of DNA are produced. Three of them are marked as 14 N superscript slash 15 N. Two other DNA was marked as 14 N slash superscript 14 N.
Remember that after a round of testing, Meselson and Stahl were able to rule out the moderate template based on the results. At that point, though, they were unable to rule out the dispersive model because that model predicts the same trend as the semiconservative model. But after two trials, the findings made it possible for them to rule out the dispersive design.
DNA is copied because it cannot fit through the nuclear membrane and travel down to the ribosome.
So it is transcribed (translated) to messenger RNA (mRNA). The mRNA can fit through the nuclear membrane and travel down to the ribosome where proteins can be made.
This is why we cannot send the entire DNA molecule itself, it is simply too big to fit. This is why mRNA is extremely important for amino acid production.
<span>The body is constantly changing, no matter what age. It has to maintain homeostasis, or balance at all times or illness/death occurs. If your body is weakened, it then becomes harder to maintain this state. If one component goes out of balance; ie, water content, it affects the whole body. Swelling(edema) CHF(serious heart problem) kidneys may be overtaxed/unable to release the extra fluid. As the body ages organs naturally become less efficient, therefore making homeostasis more challenging.</span>
But an egg or sperm only has one. That one is chosen at random, through a process called meiosis. When meiosis messes up, you can end up with to many or too few chromosomes. One extra chromosome in a egg or sperm means three in the fertilized egg and so trisomy.
