GHS Advanced Biology
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| 467755698 | Chromatin | the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins | |
| 467755699 | Nucleosome | bead-like structure in eukaryotic chromatin, composed of a short length of DNA wrapped around a core of histone proteins | |
| 467755700 | heterochromatin | Nontranscribed eukaryotic chromatin that is so highly compacted that it is visible with a light microscope during interphase. | |
| 467755701 | euchromatin | a region of DNA that is uncoiled and undergoing active transcription into RNA | |
| 467755702 | cell differentiation | The structural and functional divergence of cells as they become specialized during a multicellular organism's development; dependent on the control of gene expression. | |
| 467755703 | gene expression | conversion of the information encoded in a gene first into messenger RNA and then to a protein | |
| 467755704 | histone acetylation | The attachment of acetyl groups to certain amino acids of histone proteins. | |
| 467755705 | histone deacteylation | ... | |
| 467755706 | DNA methylation | The addition of methyl groups (—CH3) to bases of DNA after DNA synthesis; may serve as a long-term control of gene expression. | |
| 467755707 | genomic imprinting | a phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent | |
| 467755708 | epigenetic inheritance | Inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence. | |
| 467755709 | transcription factors | proteins that switch on genes by binding to DNA and helping the RNA polymerase to bind | |
| 467755710 | enhancers | A DNA sequence that recognizes certain transcription factors that can stimulate transcription of nearby genes. | |
| 467755711 | activators | chemicals that must bind for the enzyme to be active | |
| 467755712 | repressors | A protein that suppresses the transcription of a gene. | |
| 467755713 | post-transcriptional regulation | CHANGE mRNA SO THAT NO PROTEIN IS MADE or DIFFERENT VERSION IS MADE: Alternative Splicing, RNA editing (enzyme adds bases to mature RNA sequences), RNA stability (more/less stable, more/less protein, protein binding to AU rich elements within 3' UTR), RNAi (interference) | |
| 467755714 | RNA interference | technique to silence the expression of selected genes in nonmammalian organisms; uses synthetic double-stranded RNA molecules matching the sequence of a particular gene to trigger the breakdown of the gene's messenger RNA | |
| 467755715 | proteasomes | a giant protein complex that recognizes and destroys proteins tagged for elimination by the small protein ubiquitin | |
| 467755716 | oncogene | a gene that causes normal cells to change into cancerous tumor cells | |
| 467755717 | ras gene | This gene codes for Ras protein, a G protein that relays a growth signal from a growth-factor receptor on the plasma membrane to a cascade of protein kinases that ultimately results in the stimulation of the cell cycle. Many ras oncogenes have a point mutation that leads to a hyperactive version of the Ras protein that can lead to excessive cell division. | |
| 467755718 | proto-oncogene | a gene that regulates normal cell division but that can become a cancer-causing oncogene as a result of mutation or recombination | |
| 467755719 | tumor-suppressor gene | gene that codes for a protein that stops cell division in particular situations | |
| 467755720 | p53 gene | The "guardian angel of the genome," p53 is expressed when a cell's DNA is damaged. Its product, p53 protein, functions as a transcription factor for several genes. | |
| 467755721 | transposons | (jumping genes) short strands of DNA capable of moving from one location to another within a cell's genetic material | |
| 467755722 | retrotransposons | Transposable elements that move within a genome by means of an RNA intermediate, a transcript of the retrotransposon DNA. | |
| 467755723 | Alu elements | short stretch of DNA originally characterized by the action of the restriction endonuclease | |
| 467755724 | multi-gene families | group of genes that encode related products | |
| 467755725 | pseudogenes | genes that have become inactivated by mutations | |
| 467755726 | transposable elements | sequences of DNA that move around the genome. They also carry enzymes to insert themselves in different parts of the DNA. They are useful because they add diversity to the genome. |
