Study the electron dot diagrams for lithium, carbon, fluorine, and neon in figure 6-1. choose the statement that correctly identifies the most stable of the elements. a. lithium is the most stable element because it has to lose only one electron to achieve a stable configuration. b. carbon is the most stable element because it can form four bonds. c. fluorine is the most stable element because it has to gain only one electron to achieve a stable configuration. d. neon is the most stable element because its highest occupied energy level is filled.

The health, management and conservation of biodiversity, is a challenge facing ecosystems worldwide. the major factors that affect the health and function of the great barrier reef are climate change and pollution. which question investigates the effects of a biotic factor on the reef ecosystem?

Bisphenol a (often called bpa) is a chemical found in products that people use every day, from water bottles to food containers to children's toys. unfortunately, bpa leaches out of its many products and makes its way into our bodies. what are the health effects of bpa exposure? ongoing research is finding that elevated exposure to bpa can affect a wide variety of developmental and physiological processes, but one of the first studies of bpa's health effects came about because of a simple mistake in the lab. at a laboratory at case western reserve university in 1998, geneticist patricia hunt was making a routine check of her female lab mice. as she extracted and examined developing eggs from the ovaries, she began to wonder what had gone wrong. she noticed that many of the eggs showed problems with their chromosomes, and some had irregular amounts of genetic material, which can lead to miscarriages and birth defects in mammals. she learned that a lab assistant had mistakenly washed the plastic mouse cages and water bottles with a harsh soap, releasing bpa from the plastic. knowing that bpa is an endocrine disruptor, a chemical that can enter organisms and mimic hormones, hunt set out to discover whether it had adversely affected her mice.

This is a situation in which genes are attached to an organism's sex chromosomes; the sex of an organism influences the expression of a gene.