birds and mammals are both endothermic. i. e. they maintain body temperature internally through metabolism rather than from the environment. how would you explain this, given the position of the two groups of animals on the phylogenetic tree?

The picture shows a location in india that is very dry and arid. notice the tall mountains in the background; you can find high amounts of vegetation on the other side of the mountains. which statement is most likely true for this area?

Ras is a g-protein that is activated when a growth factor attaches to egfr. its activation results in the replacement of a gdp molecule with a gtp molecule, thus allowing a signal transduction pathway to be activated. considering the signal pathway illustrated on this page, what is one potential outcome of a mutation in the ras gene that leads to ras protein hyperactivity. be specific.

What if the yeast were extremely active and produced more than 100ml gas. would you know? why/why not