Ascientist suspects that the food in an ecosystem may have been contaminated with radioactive nitrogen over a period of months. which of the following substances could be examined for radioactivity to test the hypothesis
a. the cell walls of the plants growing in the ecosystem
b. the muscles of humans living in the ecosystem
c. the sugars produced during photosynthesis by plant growing in the ecosystem
d. the phospholipids in the cell membranes fo organisms living in the ecosystem

Which element is found in both dna and proteins

Determine if the following statement is true or false. if true, choose true. if false, choose the rewording that is true. according to the law of independent assortment, alleles for each gene are inherited together so that they always stay together. according to the law of independent assortment, offspring express a combination of their parents' traits. according to the law of independent assortment, alleles for a characteristic split during meiosis and combine during fertilization. true according to the law of independent assortment, alleles for each gene are inherited independently so that no two alleles stay together.

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils