Vocabulary and study material based on Ch. 19 (Eukaryotic Genome) of Campbell Reece AP Biology textbook.
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| 123187311 | Approximately how many genes are in the human genome? | 25,000 | |
| 123187312 | Chromatin | Complex DNA and proteins that make up a eukaryotic chromosome. | |
| 123187313 | Histones | Proteins that pack chromatin and have a high concentration of positively-charged amino acids. | |
| 123187314 | Nucleosome | A basic unit of DNA packaging in eukaryotes. DNA wound around a histone. | |
| 123187315 | Heterochromatin | Highly compacted, clumpy chromatin. | |
| 123187316 | Euchromatin | less compacted chromatin. | |
| 123187317 | Eukaryotic chromatin is mostly composed of... | DNA and histones. | |
| 123187318 | Cell differentiation | The specialization of cells. | |
| 123187319 | A typical human cell expresses approximately how many of its genes at a given time? | 20% | |
| 123187320 | Differential gene expression | The expression of different genes by cells within the same genome. | |
| 123187321 | Approximately what percentage of a typical eukaryotic genome codes for proteins? | 1.5% | |
| 123187322 | The expression of most genes is regulated at... | Transcription | |
| 123187323 | Histone acetylation | Addition of acetyl groups to histones, which spread the histones further apart and allow RNA polymerase to access the DNA for transcription. (One way to regulate gene expression) | |
| 123187324 | DNA methylation | Addition of methyl groups to DNA, which turns off genes and represses transcription. (One way to regulate gene expression) | |
| 123187325 | Genomic imprinting | Methylation permanently affects the genes. (One way to regulate gene expression) | |
| 123187326 | Epigenetic inheritance | Inherited changes in the phenotype that are not related to changes in the DNA sequence. | |
| 123187327 | Control elements | Segments of noncoding DNA that regulate transcription by binding certain products. (One way to regulate gene expression) | |
| 123187328 | Transcription factors | Proteins that aid RNA polymerase in initiating transcription. | |
| 123187329 | Enhancers | Control elements that are located further away from the promoter and stimulate transcription of a gene. | |
| 123187330 | Activator | Protein that works with an enhancer to stimulate transcription of a gene. | |
| 123187331 | In a eukaryotic cell, genes that code for similar functions are grouped...(together? apart?) | Apart from one another. In prokaryotic cells, however, they are all located near one another on an operon. | |
| 123187332 | Alternative RNA splicing | The process in which different proteins are created from the same RNA, depending on what is viewed as an exon or as an intron. | |
| 123187333 | microRNAs (miRNAs) | RNA that can bind to complementary sequences of mRNA and block its expression. | |
| 123187334 | RNA interference (RNAi) | Using miRNA to turn off a sequence of mRNA. | |
| 123187335 | Small interfering RNA (siRNA) | RNA that inhibits the expression of an RNA segment of the same sequence. | |
| 123187336 | Oncogenes | Cancer-causing genes. | |
| 123187337 | Proto-oncogenes | Genes that code for normal cell growth and division. | |
| 123187338 | How can a proto-oncogene turn into an oncogene? | 1. A point mutation 2. Amplification of the proto-oncogene 3. Movement of DNA within the genome (transposable elements) | |
| 123187339 | Tumor-suppressor genes | Proteins that prevent uncontrolled cellular growth. ***If a mutation strikes this, it can cause cancer (due to the absence of suppression). | |
| 123187340 | Ras proto-oncogene | Type of proto-oncogene. If mutated, it is always turned on (not good!) | |
| 123187341 | p53 tumor-supressor gene | Type of tumor-suppressant gene. | |
| 123187342 | Cancer is generally the result of an accumulation of... | Mutations, either to the proto-oncogene, the tumor-suppressant gene, or the telomerase gene. | |
| 123187343 | Can oncogenes and mutated tumor suppressant genes be inherited? | Yes. | |
| 123187344 | Transposons | "Jumping genes." Genes that can jump around in the genome (in either eukaryotic or prokaryotic cells). | |
| 123187345 | Retrotransposons | Transposons that move around via an RNA intermediate and reverse transcriptase, and that leave a copy of its original form. | |
| 123187346 | Multigene families | Collections of identical or similar genes. | |
| 123187347 | Pseudogenes | Nonfunctional DNA sequences that closely resemble gene families. |
