Down Syndrome is caused by trisomy 21.

True or false

Which of these events occurred during the Mesozoic era? Early humans began to make tools, harvest plants, and make cave paintings. Cyanobacteria filled the water and air with oxygen. Pangaea, the super continent, was formed.

How long ago did the last ice age end

What is responsible for production of oxygen by elodea

Why does the color black Absorb and white reflect?

2. All seed plants are heterosporous and produce pollen grains as well as seeds. However, there are examples of transitions between seedless vascular plants (lack seeds; generally homosporous) and seed plants.

What do cells need to do between divisions to make sure that a full set of dna gets passed on to each daughter cell?

True or false: The central nervous system allows us to sense the environment

Which of the following statements is false regarding root hairs? a. they are outgrowths of endodermal cells c. they increase the surface area of the root b. they are outgrowths of epidermal cells d. they absorb water and nutrients

Why is it critical to divide the chromosome number in half?

The amino acid proline is one of the three amino acids that watson describes as having "special properties". what is special about proline?