Answer:
1. uracil
2. nucleus
3. amino acids
4. rRNA
5. DNA and RNA are both chains of nucleotides. A sugar and phosphate backbone forms the outside helix of these molecules, and the nitrogenous bases are on the inside of the helix. The sugar used in DNA is deoxyribose, while the sugar used in RNA is ribose. DNA is double-stranded, with antiparallel strands, while RNA typically is single-stranded. Both DNA and RNA have directionality, which means that they have a 5' end and a 3' end. DNA and RNA are both synthesized from the 5' to 3' end by cellular machinery.
6. Messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA) are the three main RNA types involved in protein synthesis. mRNA carries the genetic information from the DNA in the cell nucleus to the cytoplasm to give the ribosome instructions on how to assemble the appropriate amino acids for protein synthesis. tRNA reads the mRNA message and carries the specific amino acids to be added to the polypeptide chain. rRNA assembles with ribosomal proteins to comprise the ribosome, which is the cellular machinery that produces proteins.
7. A retrovirus is a virus that uses RNA, not DNA, as its genetic material. Once a retrovirus infects a cell, it uses an enzyme called reverse transcriptase to turn its RNA into DNA, which it then incorporates into the host cell. This enables the virus to multiply and infect the organism's cells. Human Immunodeficiency Virus (HIV), the virus that leads to Acquired Immunodeficiency Syndrome (AIDS), is an example of a retrovirus.
Explanation:
