Which of the following may not have been possible without the presence of ozone in the atmosphere? Respiration may never have developed.
Oxygen may not have been able to accumulate in the atmosphere
Life may not have been able to move onto Earth’s land surfaces.
Photosynthesis may never have developed.

Average annual precipitation and are the two major features that define the biomes on earth.

Plz ! a scientist wants to produce a cow that makes a particular human protein in it’s milk the desired protein causes blood to clot and can be used to treat hemophilia (a blood clotting disorder). which of the following would be best for the scientist to use? a. genetic crosses. b. cloning. c. selective breeding. d. genetic engineering.

What is the function of the root cap? a. extra-absorbent cells in the root cap absorb more water and nutrients b. protect the meristematic area of the stem c. contains sensors for sunlight d. increases surface area of the root