For starters, humans have feelings and cells. If we get hurt we can feel things such as pain unlike a tent. If you hit a tent there is nothing it feels because it has no feelings. We have cells all through our body and rocks don't. They are made of other stuff but not cells.
The purpose of mitosis is cell regeneration, growth, and asexual reproduction,while the purpose of meiosis is the production of gametes for sexual reproduction. Mitosis is a single nuclear division that results in two nuclei that are usually partitioned into two new daughter cells. The nuclei resulting from a mitotic division are genetically identical to the original nucleus. They have the same number of sets of chromosomes, one set in the case of haploid cells and two sets in the case of diploid cells. In most plants and all animal species, it is typically diploid cells that undergo mitosis to form new diploid cells. In contrast, meiosis consists of two nuclear divisions resulting in four nuclei that are usually partitioned into four new haploid daughter cells. The nuclei resulting from meiosis are not genetically identical and they contain one chromosome set only. This is half the number of chromosome sets in the original cell, which is diploid.
They bond together creating compounds
Tyrosine is listed as a non-essential amino acid because it can be synthesised from the essential amino acid phenylalanine.
<u>Explanation:</u>
Amino acids are classified as essential and non essential according to whether they can be synthesized in the body itself or should be supplied by the diet. Essential amino acids cannot be synthesized in the body of the organism and thus can be obtained only from the diet. In the case of human beings, valine, phenylalanine, methionine etc are examples of essential amino acids.
Non essential amino acids can be synthesized within the body of the organism. Thus they need not be supplied by the diet. Alanine, aspartic acid etc are some of the non essential amino acids in human beings. It is given here that animals cannot synthesize tyrosine from shikimate-3p due to the lack of EPSP synthase.
But the amino acid tyrosine can be synthesized from the amino acid phenylalanine which is an essential amino acid. Thus tyrosine will be a non-essential amino acid.