Why is a virus considered non-living

a. a virus does not have a nucleus

b. a virus does not contain genetic material

c. a virus is to small to be considered a cell

d. a virus cannot reproduce itself without a host cell

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?

What tool do geneticists use to predict the outcome of genetic crosses? a. karyotype b. punnett square c. centrifuge

Ascientist is designing an investigation to study the impact of invasive bird populations on local, native bird populations at backyard bird feeders. what population is most likely to be a control group for the investigation? amount of food number of bird feeders invasive bird populations local backyard birdfeeders without food