In an eight-cell embryo of an organism, the cells of the upper tier are aligned over the cells of the lower tier at a slight angle. which organism is it likely to be?

earthworm

starfish

sea cucumber

sea urchin

What causes an unsaturated fatty acid to have a different shape than a saturated fatty acid? o a. unsaturated fatty acids have more hydrogen atoms. o b. unsaturated fatty acids have double carbon bonds. o c. unsaturated fatty acids have more nitrogen atoms. o d. unsaturated fatty acids have single carbon bonds.

What two fields of study provide the core information that is used to classify organisms?

Which codon is the code for the amino acid histidine (his)?