According to one scientific study, the ancient ancestor of all placental mammals was about the size of a shrew or rat. it climb trees and eight insects. It all soon after the mass extinction they kill dinosaurs. As shown by the above cladogram, several cases of mammals evolve from the common memo ancestor. Each line in the diagram represents an evolutionary lineage. The cladogram describes an example of which macroevoloutinary pattern, and for what reason?

The endoplasmic reticulum (er) is an organelle in some cells. in these cells, it is continuous with the nuclear membrane and forms a large part of the cell\'s total membrane. sort the phrases below as describing rough er, smooth er, both, or neither. note: if you answer any part of this question incorrectly, a single red x will appear indicating that one or more of the phrases are sorted incorrectly.1) found in prokaryites and uekaryotys2) involved in protein synthesis3) involve in lipid synthesis4) contains molecular chaperones in lumen5) bound with ribosomes6) involved in toxin or drug metabolism7) large systemot internnected tubules,vesicles, and sacs8) "packages" enzymes in vesicles for secretion.

What is thought to have caused the mass extinction at the end of the cretaceous period?

Are the earth's ocean floor and continents the same age geologically? why or why not?