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Term
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Definition
- is single-stranded
- contains ribose sugar instead of deoxyribose
- contains uracil instead of thymine
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Term
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Definition
| (mRNA) carries a code from DNA |
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Term
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Definition
| (tRNA) carries an amino acid |
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Definition
| (rRNA) makes up ribosomes |
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Term
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Definition
| sequence of three nucleotides which together form a unit that codes for an amino acid |
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Definition
| a sequence of three bases of a tRNA that are complementary to a codon in the mRNA |
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Term
| Transcription definition and 3 steps... |
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Definition
In the nucleus, one gene on DNA is used to code for mRNA, which will be used in a separate process to make protein.
- gene activation
- making mRNA
- splicing
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Term
| Transcription: Step 1: Gene Activation |
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Definition
| genes are activated by factors that allow the gene to unravel from its tightly coiled state and be transcribed into mRNA |
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Term
| Transcription: Step 2: make mRNA |
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Definition
RNA polymerase is the enzyme that makes mRNA by:
- binding to DNA at the start of the gene sequence
- separating the strands of DNA
- adding complementary RNA nucleotides based on sequence of DNA
- proofreading
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Term
| Transcription: Step 3: splicing |
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Definition
- add a cap to one end of pre-mRNA
- add tail to other end of pre-mRNA (cap and tail protect it)
- splice out introns (not needed sequences)
- link together exons (needed sequences for coding for proteins)
- mRNA leaves nucleus
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Term
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Definition
- initiation
- elongation
- termination
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Term
| Translation: Step 1: Initiation |
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Definition
| Translation begins with the mRNA "start" codon AUG. The first tRNA has the anticodon UAC and amino acid methionine. |
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Term
| Translation: Step 2: Elongation |
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Definition
- the 2nd mRNA codon matches a 2nd tRNA anticodon, which carries the 2nd amino acid
- a peptide bond (a kind of covalent bond) forms between the two amino acids
- the process is repeated several times
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Term
| Translation: Step 3: Termination |
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Definition
| A "stop" codon, or a codon that does not code for any amio acid, is reached, and the protein is released. |
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Definition
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Definition
| mutations in DNA that affect only one gene |
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Term
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Definition
| (a gene mutation) (aka substitution) changes one nucleotide |
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Term
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Definition
| (a gene mutation) changes the codon reading frame via a deletion or insertion of a nucleotide |
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Definition
| mutations in DNA that affect a whole segment of a chromosome, and therefore multiple genes |
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Term
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Definition
| (a chromosomal mutation) a whole piece of a chromosome is duplicated |
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Definition
| (a chromosomal mutation) a segment of a chromosome goes missing |
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Definition
| (a chromosomal mutation) a segment of a chromosome flips upside down |
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Definition
| (a chromosomal mutation) a piece of a chromosome breaks off and reattaches onto another chromosome somewhere else |
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