Which of the following accurately describes carbon atoms? a. carbon atoms are only found in two of the four main macromolecules. b. carbon atoms can bond to other carbon atoms. c. carbon atoms only have three electrons available for bonding. d. when carbon atoms bond to other carbon atoms, they can only form triple bonds.

The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.

What are the formed elements (cell or parts of cell) in blood and what are their functions ?

What are the seven economic and social goals?