Term
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Definition
(Deoxyribo-nucleic acid) consist of NUCLEOTIDES:
-pentose sugar
-with a phosphate group attached to the #5 carbon atom of the sugar
-with a nitrogenous based attached to the #1 carbon of the sugar |
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Term
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Definition
(Ribonucleic acid)consist of NUCLEOTIDES:
- a pentose sugar
-with a phosphate group attached to the #5 carbon atom of the sugar
-with a nitrogenous based attached to the #1 carbon of the sugar |
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Term
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Definition
| Nucleotides are hooked up by phosphodiester bonds b/w #3 Carbon of one sugar and the phosphated of the next nucleotide(gives 5' to 3' polarity) |
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Term
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Definition
| - all living things use DNA |
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Term
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Definition
| DNA and protein material of a eukaryotic chromosome. |
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Term
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Definition
-1 circular chromosome
-1 or more minor chromosomes (plasmids)
-Chromosome is packaged & organized into supercoiled loops attached to core
-contain topoisomerases |
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Term
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Definition
the chromosome with one copy of the organism’s DNA
Prokaryotic genome = usually 1 chromosome (Circular DNA molecule)
Eukaryotic genome = 1 HAPLOID set of chromosomes (Linear dsDNA-protein complex) |
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Term
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Definition
| an extrachromosomal ring of DNA, especially of bacterial origin, that replicates autonomously. |
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Term
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Definition
| -an enzyme that regulate the supercoiling structure of the DNA & maintain the correct conformation of DNA in the cell nucleus. |
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Term
| 2 kinds of topoisomerases |
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Definition
Type I: nicks 1 strand of dsDNA, rotates cut strand around intact strand, mends nick
Type II: cuts both strands, rotates 180’ relative to other side, mends cuts |
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Term
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Definition
varied shape and number.
examples: Borrelia burgdorferi
Agrobacterium tumefaciens
Escherichia coli |
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Term
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Definition
always circular, varied number.
examples: Methanococcus jannaschii; Archaoglobus fulgidus |
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Term
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Definition
Nucleic acid = either ds DNA, ssDNA, ds DNA, or ssRNA (+ or - strand if ss)
Form: Linear or circular
1 or more molecules
E.g.:
T-even: 1 linear dsDNA molecule
X174: 1 short ssDNA
phage: 1 linear dsDNA before injection; circularized after injection
HIV: 2 ssRNAs |
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Term
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Definition
1) Mostly diploid
2) Linear dsDNA
3) Each chromosome has unique size, shape and staining pattern in metaphase preps (karyotype)
4) Chromatin = approx. 60%protein + 40% DNA
5) Histones: abundant, small, +ve (H1,H2A, H2B, H3, H4)
6) Non-histones: varied, -ve |
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Term
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Definition
1) histones are strongly alkaline proteins which package and order the DNA into structural units called nucleosomes.
2) They are the chief protein components of chromatin, act as spools around which DNA winds, and play a role in gene regulation.
3) Without histones, the unwound DNA in chromosomes would be very long. For example, each human cell has about 1.8 meters of DNA, but wound on the histones it has about 90 millimeters of chromatin, which, when duplicated and condensed during mitosis, result in about 120 micrometers of chromosomes. |
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Term
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Definition
1) true” chromatin
2) Coils / uncoils with cell cycle
3) Most of genome
4) Actively transcribed
5) No repetitive sequences |
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Term
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Definition
1) other” chromatin
2) Stays condensed
3) Stains dark
4) Replicates later
5) Transcriptionally inactive
6) Contains repetitive sequences
7) Often has methylated CGs
8) Facultative or constitutive |
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Term
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Definition
1) INTERSPERSED
2) Tandem repeats |
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Term
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Definition
1) Irregular intervals
2) Includes LINEs and SINEs |
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Term
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Definition
1) nucleotides is repeated and are directly adjacent to each other.
2)includes highly repetitive satellites, and moderately repetitive minisatellites, and microsatellites. |
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Term
SINEs- 9% HUMAN GENOME
(Short INterspersed Elements) |
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Definition
1) 100-400 base-pair (bp) long
2)Nonfunctioning DNA of parasitic origin
E.g. Alu family of SINES
200-300 bp long
3) Repeated 1,000,000 times
4) Probably leftover virus that got stuck in genome
5) Some may still be able to hop around genome (transposons), but do not encode own hopping enzyme (transposase)
Gene disruption causes e.g. NF1 |
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Term
LINEs 15% FOR TOTAL HUMAN DNA
(Long INterspersed Elements) |
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Definition
1) Similar to SINEs but 1000-7000 bp (1-7 kb) long
2)nonfunctional BUT may hop around genome (“transposons”) and cause gene disruption (e.g. some hemophilia)
E.g. LINE-1
repeated 500,000 times
3) Most 1-2 kb, some 6-7 kb
Longer ones can hop around |
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Term
TRANSPOSONS
aka jumping gene
aka transpostion |
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Definition
1) are sequences of DNA that can move around to different positions within the genome of a single cell.
2) can cause mutations and change the amount of DNA in the genome. |
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Term
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Definition
1)describes a pattern that helps determine an individual's inherited traits
2)1000-several repeats
3)1000 bp long core repeat
4) Repeated in large clusters (up to 100 million bp)
5) In heterochromatic regions near centromere and telomeres
6) Also plentiful on Y chromosome
7) May protect chromosome ends |
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Term
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Definition
1) 9-24 base-pair (bp) core repeat unit, 0.5-30 kb total array length
2) Often near telomeres
3) Not usually transcribed: function unclear
4) Can be dangerous; microsatellite defects associated with some cancers |
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Term
Microsatellites
a.k.a. STR (Short Tandem Repeats)
a.k.a. SSR (Simple Sequence Repeats |
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Definition
1) shorter core repeat unit (2-4 bp)
10-100 typical copy number (in each block) at 50,000-100,000 loci scattered throughout human genome
2) Function unknown
3)Also associated with cancer; some trinucleotide repeats are pathogenic, e.g. too many in Huntington’s Disease, Myotonic Dystrophy, fragile X Syndrome, possibly schizophrenia/bipolar disorder.
4) May be used for DNA fingerprinting |
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