Iam:
double stranded
found in the nucleus
have four nitrogen bases
contain deoxyribose sugar
contain thymine instead of uracil
what important molecule am i?

A)  DNA

Explanation: DNA is a double helix molecule; it is double stranded. It is found only in the nucleus of eukaryote cells. The building blocks of DNA are nucleotides. Each nucleotide contains of a 5-carbon deoxyribose sugar, one of four nitrogen bases attached to the sugar, and a phosphate group.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.