The bones of the skeletal system serve to protect the body's organs, support the weight of the body, and give the body shape. The muscles of the muscular system attach to these bones, pulling on them to allow for movement of the body.
Bone structures. Our hands and feet are similar along with our teeth
F1 gens are basically the first group of offspring, and F2 are the offspring from interbreeding the F1 gen. then you create a punnet square using the parents genes, from there you can write the expected genotypes, so i think in this case it would be [ depending on parents ] rr , Rr, and RR.
Obsidian is an extrusive rock that is formed when magma from underneath the Earth's crust breaches and becomes lava. Once the lava starts cooling, it solidifies and elements are frozen, giving the rock its glassy appearance.
Acid rain can be very harmful, mildly harmful, or not harmful at all. It mainly depends on the density of the rain, and how bad the current air pollution in the area is. Also, it depends on how often the area gets acid rain. The first few times an area gets acid rain, it's nearly harmless. Then, the next few it can be very dangerous, but eventually gets weaker over time. More air polluted areas are more likely to get much more harmful acid rain.
Summary: Acid rain is usually mildly harmful, mostly only harmful to infrastructures.<span />