What is the evidence that glaciers once existed on all of the southern continents? A. Grooves in the rocks and sediment deposits.
B. Fossil evidence of cold weather species.
C. Radioactive isotopes in the ice cores
D. Large glacial lakes still exist

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?

Nucleic acids offer variability because they contain alternate forms of genes called .

Label the steps for protein synthesis in order, beginning with the first steponce the protein is made, the gene for a particular trait is expressedmrna joins the ribosome, and the anticodons from trna join mrna to form a chain ofamino acidsrna polymerase unzips dna and free rna nucleotides join dna to form mrnav a chain of amino acids is formed from peptide bonds, creating a proteinmrna is transported from the nucleus of the cell to the ribosomes of the cell.