Which combination of alleles best describes a sex-linked trait?
a. heterozygous alleles
b. homozygous alleles
c. alleles that are carried on x and y chromosomes
d. alleles that are carried on somatic cells

Embryonic stem cells are cells derived from an embryo. these cells can be used to create new tissues for patients suffering from certain illnesses and disorders. which statement best summarizes why the use of embryonic stem cells could be seen as unethical? a. some people consider embryos to possess rights equal to those of fully developed human beings. b. extracting stem cells from embryos is a very energy-intensive process, which consumes resources that could be used elsewhere. c. embryos are difficult to obtain, so the monetary cost of using them for research outweighs their benefit. d. the process of extracting stem cells from embryos generates biohazardous waste that cannot be safely disposed of.

Water, wind, and solar energy can be replenished over relatively short time spans, so they are called renewable resources nonrenewable resources unreplenished resources exhausted resources

Use the drop-down menus to determine which structures of the exocrine system are described below. secrete mucus that protect organs secretes enzymes that aid in digestion secrete tears keep the skin hydrated and soft