Katie designed an experiment using a paint roller pan, sand, and water. The steps of the experiment are listed below.

Put 3 inches of moist sand on a paint roller pan.
Make a beach by scooping the sand toward the higher portion of the pan.
Pour water into the deeper end of the pan.
Use a straw to blow on the water for 2 minutes to create waves.
Observe how the sand is displaced by the waves.

Katie's model most likely represents the interactions between the
atmosphere, hydrosphere, and geosphere
atmosphere, ocean, and biosphere
cryosphere, biosphere, and ocean
geosphere, ocean, and biosphere

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.

Can a trait be both polygenic and have multiple alleles? explain why or why not.

Northern switzerland has a fairly cold climate caused by sea winds from the atlantic ocean but souther switzerland tends to be much warmer and sunnier, what could cause this difference?