What is it called when a high percentage of the species on earth dies off at a particular time

In a balanced ecosystem, the number of is far greater than the number of.

Taconite is a low-grade iron ore that is found around Lake Superior. The iron-bearing rock is found interlaced with quartz, chert and other minerals.

Which one of these exhibits a notochord at some stage in its development. A. a cat B. a hydra C. a brittle star D. a tapeworm

Why are the mutations generated in a species' gene pool important? A. The mutations reduce variation. B. The mutations prevent inbreeding. C. The mutations maintain equilibrium. D. The mutations cause evolution.

Windup, if it occurs, is seen in animals A. during an extended surgical procedure. B. after recovery from general anesthesia. C. after analgesic is administered. D. during administration of general anesthesia

Suppose you remove your test cultures from the incubator and notice that one of them-a known fermenter-has a gas bubble in the Durham tube. Knowing that fermenters frequently produce gas, you ignore the bubble and proceed to the next step.

In peas, yellow seed color (y) is dominant to green seed color (y). which describes an organism that has nonidentical alleles for seed color? yy and has green seeds yy and has yellow seeds yy and has yellow seeds yy and has green seeds

What would you expect to happen if sea otters were removed from this food web? Check all that apply. The population of elephant seals would decrease. The population of kelp crabs would increase. The population of kelp would increase.

When blockages in the bloodstream read the Brian it can cause blank?

A gazelle is born with slightly longer legs which allow it to run faster than the other gazelles in the herd. This adaptation came may have come about because a. the gazelle needed to be able to run faster. b.