Collagen is a part of the connective tissue that in the skin helps in firmness, suppleness and constant renewal of skin cells. Collagen is vital for skin elasticity. Ligaments are another type of connective tissue that attach two bones and consequently hold the joints together.
There are at least 33 phyla (plural of phylum) of animals. Humans are members of the phylum Chordata. All of the chordates have elongated bilaterally symmetrical bodies. That is to say, the left and right sides are essentially mirror images of each other.
The percentage of genes or DNA that organisms share records their similarities. We share more genes with organisms that are more closely related to us. Humans belong to the biological group known as Primates, and are classified with the great apes, one of the major groups of the primate evolutionary tree.he percentage of genes or DNA that organisms share records their similarities. We share more genes with organisms that are more closely related to us. Humans belong to the biological group known as Primates, and are classified with the great apes, one of the major groups of the primate evolutionary tree.