The heart and arteries are key structures in which system?
a.
digestive system
b.
nervous system
c.
respiratory system
d.
circulatory system

Support mangrove trees out of the water. a) pneumatophores b) prop roots c) sand dunes d) tide supports

The periodic table houses noble gas elements in group 18. these elements are highly stable and rarely react with any other elements. what is one possible reason for the stability of the noble gas elements? a. they easily form covalent bonds. b. the compounds that they form with other elements are very unstable. c. their outermost shell has the maximum number of electrons that it can hold. d. they require less activation energy.

For each of the following situations, determine whether the population is in hardy-weinberg equilibrium or is evolving.