Genetics.

1. RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell
3. three-nucleotide sequence on messenger RNA that codes for a single amino acid
6. Down syndrome,extra chromosome 21
8. An allele that is masked when a dominant allele is present
12. A change in the structure of a chromosome
13. An organism's genetic makeup, or allele combinations.
14. The control center of the cell
16. A chart that shows all the possible combinations of alleles that can result from a genetic cross
18. the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei.
19. group of three bases on a tRNA molecule that are complementary to an mRNA codon
20. A complex molecule containing the genetic information that makes up the chromosomes.
21. the organic process whereby the DNA sequence in a gene is copied into mRNA

2. site of protein synthesis
4. type of RNA molecule that transfers amino acids to ribosomes during protein synthesis
5. A display of the chromosome pairs of a cell arranged by size and shape.
7. An organism's physical appearance, or visible traits.
9. synthesis the formation of proteins by using information contained in DNA and carried by mRNA
10. having two different alleles for a trait
11. A genetic trait is considered dominant if it is expressed in a person who has only one copy of the gene associated with the trait.
15. Process of making changes in the DNA code of living organisms
17. An organism that has two identical alleles for a trait