The biotic factors of the North American ecosystem that influence lodgepole pine populations are A.
fire, pine beetles and fungus

B.
clear cutting by lumber companies and -25 oC winter temperatures

C.
the mountain pine beetle parasite and fungus

D.
warm dry summers and cold wet winters

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?

Drag each description to the correct location on the image. not all descriptions will be used. describe the parts of a comet. the frozen part of the comet the atmosphere of gases and dust formed when the nucleus vaporizes tail made of small, solid dust particles tail made of ions that appears to point away from the comet's orbit

Which label identifies the part of the atp molecule that changes when energy is released in the cells of all living things