Let's make the alleles Tt, where T is dominant (tongue rolling) and t is recessive (inability to tongue roll).
The heterozygous tongue roller would be Tt and the non tongue roller would be tt. Putting them in a punnet square (refer to attachment), the chances that their child will be a non tongue roller would be a 50% chance.
Tt: 2/4 = 50%
tt: 2/4 = 50%
Explanation:
Many invertebrate animals cant survive in water that has been polluted and resulted in a lowering of oxygen concentration so the presence or absence indicates the extent to which a body of water is polluted.
Lichens can be used to indicate air pollution as they grow exposed to places such us rocks and tree barks. They need to be efficient at absorbing water and nutrients to grow there. Rain water contains enough nutrients to keep them alive. Air pollutants dissolve in rain water especially sulfur dioxide can damage lichens and prevent them from growing. This makes them a natural indicator of air pollution.
It is found in Continental Shelf. Many of the shelves were
seen during glacial periods and interglacial periods. Surrounding the shelf is
an island is known as an insular shelf. The continental shelf is a landmass underwater
thus extends from a continent, the reason in an area of relatively shallow
water known as a shelf sea.