Which is a reason that protists are difficult to classify?

A: They are too small.
B: They are all eukaryotes.
C: They have been classified based on what they are not.
D: They have too many shared characteristics.

Which organelles are labeled d, and what is one feature that distinguishes them from the other labeled organelles chloroplasts the only organelles that produce sugars from sunlight mosomes, only found in animal and bacterial cells centricles only found in animal cells mitochondra, the only energo-generating structures found in cells

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

14. which of the following codons code for threonine? a. ucg b. ugu c. cga d. aca