Which of the following statements about the earth’s atmosphere is true?

a.
in the past few decades, carbon dioxide levels have been rising.

b.
in the past few decades, carbon dioxide levels have been falling.

c.
a recent increase in carbon dioxide levels can contribute to a long-term cooling of earth’s climate.

d.
a recent decrease in carbon dioxide levels will increase plant growth on earth.

this is science

What are the fixed alleles in the human species? o a. the alleles that are on the most chromosomes b. the alleles that change most often 000 c. the alleles that no one has d. the alleles that everyone has

Agroup of plant cells was exposed to radiation, which damaged the chloroplasts and caused them to lose function. if the mitochondria were unharmed, what would happen to the overall function of the plant cells? a. the cells would not be able to make food, but would be able to release energy from biomolecules. b. the cells would not be able to replicate dna, but would be able to break down waste. c. the cells would not be able to break down waste, but would be able to replicate dna. d. the cells would not be able to release energy from biomolecules, but would be able to make food.

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes