| A | B |
|---|
| activator | stimulates transcription of a specific gene |
| alternative RNA splicing | different mRNA molecules are produced from the same primary transcript |
| cell differentiation | structural and functional divergence of cells as they become specialized |
| chromatin | complex of DNA and proteins that makes up a eukaryotic chromosome |
| control element | noncoding DNA that helps regulate transcription of a gene by binding with transcription factors |
| differential gene expression | expression of different sets of genes by cells with the same genome |
| enhancer | DNA segment containing multiple control elements that may be located far away from the gene it regulates |
| epigenetic inheritance | Inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence |
| euchromatin | open |
| genomic imprinting | expression of an allele in offspring depends on whether the allele is inherited from the male or female parent |
| heterochromatin | nontranscribed eukaryotic chromatin that is so highly compacted that it is visible with a light microscope during interphase |
| histone | proteins that bind to DNA to form nucleosomes in chromatin |
| histone acetylation | attachment of acetyl groups to certain amino acids of histone proteins |
| micro-RNA (miRNA) | directs associated proteins to degrade or prevent translation of the target mRNA. |
| multigene family | collection of genes with similar or identical sequences |
| nucleosome | segment of DNA wound around a protein core composed of two copies of each of four types of histone |
| oncogene | part of viral genome that triggers cancerous characteristics |
| p53 gene | expressed when a cell’s DNA is damaged. Its product acts as a transcription factor for several genes |
| proteasome | recognizes and destroys proteins tagged for elimination |
| proto-oncogene | gene with a potential to cause cancer but that requires some alteration |
| pseudogene | DNA segment very similar to a real gene but which does not yield a functional product |
| Ras gene | produce growth signal matches membrane receptor to stimulate cell cycle |
| repetitive DNA | noncoding sequences present in many copies in a eukaryotic genome |
| repressor | suppresses the transcription of a gene |
| retrotransposon | transcript of the retrotransposon DNA |
| RNA interference (RNAi) | technique to silence the expression of selected genes |
| transcription factor | binds to DNA and stimulates transcription of specific genes |
| transposon | genetic element that moves within a genome by means of a DNA intermediate. |
| tumor-suppressor gene | gene whose protein products inhibit cell division |
