Answer:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. The skin, nails and hair form the integumentary system, which stops dirt and pathogens from entering the body.
A hydrometer is an instrument that measures the specific gravity (relative density) of liquids. The ratio of the density of the liquid to the density of water. A hydrometer is usually made of glass, and consists of a cylindrical stem and a bulb weighted with mercury or lead shot to make it float
The advertisers treat teenagers as separate target audiences by having to advertise products that would attract the teenagers alone as the teenagers are not particularly attracted to things that they may target the adult audiences, that is why, they laid out products that would target the teenagers in means of separating the target audiences.
A lot of DNA is structural and doesn't pertain to any genetics while it only takes a small change to change something big. DNA mainly uses 4 different chemicals to change itself, not giving a lot of variety. Most animals share around 98% of the same dna with each other. Humans share 50% of their DNA with a banana. Pretty much everything shares the same double helix design as well. So a lot of genetic code looks similar.
