Desertification may be caused by
water pollution
smog
rain
overgrazing

Can a trait be both polygenic and have multiple alleles? explain why or why not.

The structure of a dna molecule is best described as a. one long strand of nucleic acids b. two strands of dna nucleotides joined by hydrogen bonds c. two strands of amino acids joined by hydrogen bonds d. one long strand of amino acids

During photosynthesis, hydrogen ions are most directly used to in the chloroplast pictured above. a) make glucose b) make chlorophyll c) produce carbon dioxide d) drive the production of atp