Term
| How many base pairs of DNA do humans have? |
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Definition
| Humans have 3 billion base pairs |
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Term
| Humans have how many chromosomes? |
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Definition
Humans have 46 chromosomes or
23 homologous pairs
22 pairs autosomes
1 pair-sex chromosomes |
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Term
| Name 6 excellent test subjects for Genetic Research? |
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Definition
Drosophila melanogaster - Fruit Fly
- The name Drosophila means dew lover and - melanogaster means black bellied.
advantages:
small size
short generation time (10 days) at room temp
each female lays 400-500 eggs
easy to culture in a laboratory
small genome
large chromosomes
many mutations available
Escherichia coli - Bacerium
Caenorhabditis elegans - Roundworm
Arabidopsis thaliana - Thale Cress Plant
Mus Musculus - House Mouse
Saccharomyces cerevisiae - Baker's Yeast |
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Term
Prokaryotes vs. Eukaryotes
nuclear envelope
genomic DNA |
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Definition
Prokaryotes have no nuclear envelope, eukaryotes do.
P - circular genomic DNA, E - Linear genomic DNA
P - Plasmids, Extra-chromosonal, circular, autonomously replicating DNA
E - Mitochondrial or chloroplast DNA is prokaryotic-like and provides maternal or cytoplasmic inheritance
P - Prokaryotic cell division involves the replication of the prokaryotic genome followed by division of the cell. |
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Term
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Definition
| Alternate form of the same gene |
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Term
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Definition
Homozygous-2 identical alleles
Expressed when present |
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Term
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Definition
| Masked by dominant, observed only in the homozygote state |
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Term
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Definition
| Two alleles of the same form |
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Term
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Definition
| Hybrids - one of each of 2 types of alleles |
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Term
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Definition
One functional allele
Null mutation
Dosage compensation – same # of x linked transcripts for both |
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Term
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Definition
| Genetic makeup AA, Aa or aa |
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Term
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Definition
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Term
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Definition
| Identical in structure similar in content |
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Term
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Definition
| 2 sets of chromosomal types – two sets of 23 chromosomes or 23 homologous pairs in humans |
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Term
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Definition
| One set of chromosomes – could be a natural state for some species (yeast) or it could be the amount of genetic material present in gametes |
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Term
Prokaryotic Cell Division
Origin of Replication |
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Definition
In prokaryotes, as the chromosome replicates, the origins segregate to opposite side
The origins are anchored to opposite sides of the cell
The cell divides. Each new cell has an identical copy of the original chromosome |
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Term
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Definition
Eukaryotic cell division requires replication of the DNA during the S-phase of the cell cycle and division during M- phase
In order to safely divide the cell the DNA must be packaged into tightly packaged structures called chromosomes.
During Interphase
DNA is packaged to prevent shearing forces from damaging the DNA. The packaging also helps in regulation of gene expression at this level
During Cell Division
DNA is tightly packaged to prevent damage during chromosomal movements |
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Term
| Packaging during Interphase |
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Definition
Packaging in Nuclei
DNA is packaged with lots of proteins
Chromatin - beads on a string
String = DNA
Beads = Histone octamer
Histone octamer-
2 of each histone H2A
2 of each histone H2B
2 of each histone H3
2 of each histone H4
Nucleosome
DNA wrapped 2 times around histone octamer
Linker DNA-links nucleosomes
Linker DNA-contains histone H1 (5th type of histone) |
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Term
| Packaging during Cell Division |
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Definition
Step One
Solenoids - 6 nucleosomes/360˚ turn also known as the 30nm fiber
In solenoid formation Histone H1 acts as a latch to latch 2 adjacent nucleosomes together. End result looks very much like a toy slinky.
Step two: Chromatid and Chromosome Formation
Scaffolding proteins will lay down the foundation for chromosomes
Solenoids will complex with the scaffolding proteins forming chromatids
Two sister chromatids are attached at their centromeres forming chromosomes |
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Term
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Definition
Metacentric: Centrally located centromere
Very submetacentric: Displaced centromere
More towards the top of the chromosome
Acrocentric: Extremely short p-arm (top region) in relation to q-arm (bottom region of chromosome
Telocentric: The centromere is just below telomere
Not found in humans, found in rodents |
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Term
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Definition
Ploidy refers to the number of sets of chromosomes that are present
Euploids have complete ploidy’s
Diploid is 2n or for humans 2x23 types of chromosomes or 46 chromosomes
2 represents # of sets of chromosomes
n - # of types of chromosomes
Haploid – n is a normal state for haploid organisms or for gametes (sperm or egg)
Monoploid – n – abnormal state
Triploid – 3n Can be normal for some plants abnormal for humans
Tetraploid – 4n Can be normal for some amphibia and plants, abnormal for humans
Aneuploids do not have true ploidy:
For instance
2n + 1 individual has an extra chromosome
47 (2n + 2l) is the designation for a person with Down Syndrome. They have an extra 21st chromosome. Often it would be recorded as 47 XX (2n + 2l) or 47 XY (2n + 2l) for female or male, respectively.
2n – 1 individual is missing a chromosome.
45, XO is a female with turner Syndrome. She is missing one of the sex chromosomes |
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Term
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Definition
process by which a diploid somatic cell (2n) will give rise to 2 diploid somatic (2n) cells. Mitosis is cloning of your somatic cells
In humans 23 pairs of chromosomes all 46 chromosomes line up in the center of the cell and the sister chromatids are divided into daughter cells. Each daughter cell gets one of the original sisters of each member of the homologous pairs. |
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Term
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Definition
process by which a diploid (2n) gametocyte (sex cell) gives rise to 4 haploid (n) daughter cells (some of these cells may not be functional)
A 1˚gametocyte has 2n (diploid) worth of chromosomes. Homologous pairs are bound together. Two stages of meiosis
1st meiosis the homologous pairs separate creating haploid (n) daughter cells.
2nd meiosis is identical to mitosis except the cell was haploid (is haploid) |
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Term
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Definition
| The stages of mitosis that we will discuss are prophase, metaphase , anaphase and telophase. We identify the characteristics of the cell in the middle of each phase. Be aware the process of mitosis is dynamic. The cell does not jump to the middle of a phase but rather flows into that phase. |
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Term
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Definition
Centrioles divide and separate
Nuclear envelope begins to breakdown
Nucleolus disappears
Chromosomes start to condense and nucleus looks like a ball of yarn |
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Term
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Definition
Nuclear envelope completely gone
Centrioles 180˚ apart
Chromosomes most condensed state
Spindle fibers connect centriole (centrosome) to centromere (kintechore). Spindle fibers are mictotubules.
Chromosomes lined up on metaphase plate (equatorial plate) |
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Term
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Definition
| Sister chromatids separate |
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Term
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Definition
Nuclear envelope begins to reform
Nucleolus reappears
Cleavage furrow forms (pinching in the membrane) - in plants get cell plate
Chromosomes decondense
Centriole will end up in separate daughter cells ends with two diploid cells |
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Term
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Definition
There are two stages to meiosis. Meiosis I (Reduction Division) is a reduction division in which the number of chromosomes are reduced. Meiosis II (Equational Division) is identical to mitosis except that the cell was haploid at the start.
Interkinesis is a brief period between meiotic divisions. The cells appear to be in interphase except that the cell is haploid and DNA does not replicate (it replicated during S-phase of interphase and the sister chromatids represent this replicated DNA).
The stages of meiosis are prophase I, metaphase I, anaphase I, telophase I, prophase II, metaphase II, anaphase II, and telophase II. We identify the characteristics of the cell in the middle of each phase. Be aware the process of meiosis is dynamic. The cell does not jump to the middle of a phase but rather flows into that phase. |
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Term
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Definition
Nuclear envelope begins to breakdown
Nucleolus disappears
Centrioles divide and separate
Chromosomes begin to condense
Chromosomes undergo synapsis which is a pairing processes
Crossover events occur
Synapsis:
Pairing processes by which homologous chromosomes come together. Forms synaptonemeal complex.
Synaptonemeal complex:
Forms during synapsis to fuse homologous chromosomes together.
Crossover (C.O.) events:
Both rare and common; common because on average you can have 3 C.O. events per arm of chromosome pair #1. Rare because the event is random as to the section of the arm. |
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Term
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Definition
Nuclear envelope completely gone
Homologous pairs are lined up on the metaphase plate.
Centrioles and centromeres are connected through spindle fibers
Centrioles are 180˚ apart |
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Term
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Definition
| Homologous chromosomes separate |
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Term
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Definition
Cleavage furrow forms (or cell plate in plants
Nuclear envelope reforms
Nucleolus reappears
Chromosomes decondense
End of telophase I have 2 haploid cells |
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Term
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Definition
Same as mitosis except you have ½ the # of chromosomes.
You go through the stages of
Prophase II, Metaphase II, Anaphase II, Telophase II |
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Term
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Definition
| occurs principally during telophase and is the division of cytoplasmic material. |
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Term
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Definition
| occurs during prophase to telophase stages of mitosis, meiosis I and meiosis II. It is the movement of nuclear material or division of the nucleus |
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Term
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Definition
In Mitosis and meiosis, cohesin keeps the 2 sister chromatids (homologs) together at chiasmata.
Cohesin breaks down in Anaphase, allowing the sister chromatids to separate |
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Term
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Definition
| In Meiosis, shugoshin keeps the protects the cohesin at centromere in Anaphase I, but the shugoshin breaks down in Anaphase II, which allows the cohesin to break down and the sister chromatids to separate. |
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Term
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Definition
| is the production of 4 mature sperm cells from each primary spermatocyte. The primary and secondary spermatocytes underwent equal karyokinesis and equal cytokinesis. |
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Term
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Definition
| is the production of one mature egg sell (ovum) from each primary oocyte. The primary and secondary oocytes underwent equal karyokinesis but unequal cytokinesis. Leaving one large egg cell. |
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Term
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Definition
| A genetic factor (region of DNA) that helps determine a characteristic |
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Term
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Definition
| Specific place on a chromosome occupied by an allele |
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Term
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Definition
says that the alleles for a given gene are inherited separately.
Take a coin and flip the coin one time. You can obtain either a head or a tail but can not get both.
Mendels Principle of Segregation is based upon homologous chromosomes separating during Anaphase I of Meiosis. One of the homologues will end up in each of the daughter cells, (barring mutation). |
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Term
| Principle of independent assortment |
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Definition
says that the alleles of genes on different chromosomes will be inherited independently from each other.
Independent Assortment:
Take two coins of different denominations and flip them. For each coin you can obtain a head or a tail but not both. For the two coins together you can obtain two heads, two tails, a head and a tail or a tail and a head, respectively. The two coins and their respective outcomes are independent from each other.
Mendels Principle of Independent Assortment is based upon the homologous chromosomes lining up independent from each other on the equatorial plate during Metaphase I of Meiosis. One set of homologues will end up in each of the daughter cells, (barring mutation). |
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Term
| Dominant verses Recessive |
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Definition
Dominant alleles are expressed when present. Therefore these alleles are inherited from a parent that is exhibiting the characteristic. A child will inherit the characteristic only if a parent has it. The child only needs to inherit one copy of the allele to express the allele.
Recessive alleles are masked by a dominant allele. The characteristics encoded by these alleles are expressed when the individual has two copies or is hemizygous for one copy. A child will express the recessive characteristic if the child inherits a recessive allele from each parent. The parent does not have to exhibit the characteristic but must have an allele for that phenotype. |
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Term
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Definition
Pea plants tend to be self-fertilizing so some precautions must be taken to prevent this. In the case of animals you would put females of a specific genetic makeup with males of a different make-up.
Sometimes you want plants to self-fertilize to see what offspring will be produced from the individual plants genetic makeup. In this instance you would not remove the anthers and would not cross pollinate. This process is referred to as selfing – self-fertilizing. In the case of animals you would allow male and female offspring to mate and then remove the parents. |
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Term
| Relationship between classical genetics and meiosis |
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Definition
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Term
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Definition
| A test cross is a test for heterozygosity. It is when you cross an individual with a homozygous recessive for all traits. It allows you to determine if the parent of interest is heterozygous for one or more of those traits. |
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Term
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Definition
The dihybrid cross involves crosses using two genes. These crosses follow Mendels’ Principle of Independent Assortment -
Alleles of genes on different chromosomes will be inherited independently from each other. |
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Term
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Definition
There are many mechanisms that determine the sex of individual members of a species.
If an individual has two of the same type of sex chromosome they are referred to as the homogametic sex (XX). If they have two different types of chromosomes they are the heterogametic sex (XY). |
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Term
| Sex Determination - Mammals |
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Definition
The presence of the Y chromosome tends to denotes maleness. Female is the default pathway for mammals. Individuals with one or more X chromosomes but no Y chromosome are females.
The SRY (sex-determining region) gene on the Y chromosome causes testes to form which produce testosterone. Testosterone normally causes male development. XY individuals are males |
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Term
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Definition
There are cases in which XY individuals are female. These individuals either do not make androgenic hormones or are insensitive to these hormones.
1) If an individual has a null mutation for the SRY gene then they do not form testes and do not produce testosterone. These individuals will be phenotypic females but genotypic males.
2) A gene on the X chromosome codes for androgen receptors. If this gene is mutated then the androgen receptors are insensitive to the testosterone that is produced. These individuals are phenotypically female but genotypically male with functioning internal testes. |
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Term
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Definition
| There are cases in which XX individuals are male. These individuals have the SRY gene transposed to the X chromosome. These individuals will be phenotypic males but genotypic females. |
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Term
| Sex Determination- Drosophila |
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Definition
| In Drosophila and many other insects the ratio of X chromosomes to sets of autosomes determines if the individual is male (one X: two sets of autosomes) or female (two X: two sets of autosomes). The default pathway is male. The next slide shows how the X:A ratio affects the phenotype of the fly. |
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Term
| Sex Determination - Birds |
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Definition
| In Birds, snakes, butterflies, some amphibians, and fishes the males are ZZ and females are ZW. This is the opposite for other organisms so we use the ZW symbols as opposed to XY symbols |
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Term
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Definition
The human egg is much larger than the human sperm. This is due to two phenomenon.
The oocyte is enlarged due to unequal cytokinesis during meiosis
The sperm is reorganized and compacted during the maturation process. Most internal organelles have been rearranged or removed to form the tightly packed head of the sperm which contains the male pronucleus (haploid) and an acrosome (helps in fertilization). There is significantly less cytoplasm in a mature sperm than in other cells |
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Term
| X and Y – Homologous?????????? |
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Definition
1) We have defined homologous chromosomes as identical in structure and similar in content.
2) We claim that homologous chromosomes attach to each other through the synaptonemeal complex and therefore are able to line up on the metaphase plate during Meiosis I.
3) The X chromosome is a metacentric chromosome. The Y chromosome is acrocentric.
4) The X and Y chromosomes have very few genes in common.
Answer: Yes and no. The X and Y chromosomes do have some homologous regions called the psuedoautosomal regions that allow them to form synaptonemeal complexes. They are different at other regions. They do pair and line up on the Metaphase I plate and they separate during Anaphase I.
The primary pseudoautosomal region is on the end of the short arms, and the secondary pseudoautosomal region is on the ends of the long arms (bottom) |
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Term
Sex-Linked Traits
XY organisms |
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Definition
Y-linked traits are passed from father to son.
X-linked traits (do not have a comparable Y-counterpart) are passed from father to daughter and mother to child. The expression of the traits in the daughter is dependent on the same factors as for any autosomal trait. The expression in the son is that the trait will be expressed when present.
Determination if a trait is sex-linked. If you have an expression of the trait differently between male and female offspring than the trait is sex-linked. Whenever you see difference in the number of males verses females for a given trait you know the trait is sex-linked. |
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Term
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Definition
Drosophila melanogaster - Fruit Fly
- The name Drosophila means dew lover and - melanogaster means black bellied.
advantages:
small size
short generation time (10 days) at room temp
each female lays 400-500 eggs
easy to culture in a laboratory
small genome
large chromosomes
many mutations available
Life cycle:
1 day as an egg
1 day 1st instar
1 day 2nd instar
1 day 3rd instar
3rd instar for 2-3 days
pupates for 3-4 days
adult
can reproduce is one day
3 pairs of autosomes and 1 pair sex chromosomes
approximately 50% of genes shared with humans
males have bristles for forelimbs (sex combs), rounded abdomen, genitalia, and darker color
females have pointed abdomen, not dark, bigger than males |
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Term
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Definition
| The + symbol represents wildtype which is the type most commonly found in nature. The wildtype does not have to be the dominant but most often it is the dominant. In the case of red eyed flies the wildtype is the dominant. It is not wrong to use XW. |
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Term
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Definition
used to determine if sex-linked recessive or dominant. If differences turn out between males and females, they are sex-linked.
Differences between the numbers of male and female offspring indicate sex linkage. If you complete the two crosses on the previous slide you notice that a white eyed homozygous recessive female crossed to a red eyed hemizygous male gives all white eyed sons and all red eyed daughters. This indicates the trait is sex-linked.
The father gives his X chromosomes with the red allele to his daughters. Since red is dominant his daughters express the red eye color. The mother gives her X chromosomes with the white allele to her children. This is then expressed in her hemizygous sons since they do not have a comparable allele from their father. They inherit the Y chromosome from their father.
Note the reciprocal cross yielded all red eyed offspring. From this cross you can not tell sex-linkage until the F2 generation. |
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Term
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Definition
Dosage compensation is a mechanism by which species compensate for the differences between the sexes at least with regard to the number of X-linked transcripts. Males and females may have a different number of X chromosomes but they produce the same number of X linked transcripts.
It would be lethal for the species if the genes on the X chromosome were not regulated since the number of transcripts synthesized correlate to the number of proteins produced which in turn have specific functions in the cell. If you have too many copies in the female and too few copies in the male it upsets the balance. These differences must be compensated. |
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Term
| Dosage Compensation Mechanisms |
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Definition
Mammals: X-inactivation – The all but one rule says that all but one X-chromosome will be inactivated in any given cell. Inactivated X chromosomes are heterochromatic and are referred to as Barr bodies.
In normal males their single X chromosome is functional in each cell. In normal females one X-chromosome is functional and one is inactivated randomly in each cell. The next slide shows a normal female cat which is heterozygous for orange and black coat color. Coat color is located on the X chromosome in cats.
In individuals who have too many X chromosomes such as a male with Klinefelters syndrome all but one X-is inactivated.
In a female with only one X and no Y chromosome (Turners syndrome) the single X chromosome is functional in all cells.
It should be noted that Barr bodies are “leaky” which means that there are some genes that are transcribed completely and some others to low levels. It is due to this “leakiness” that the phenotypic characteristics of individuals with too many X chromosomes are observed.
The next slide is a table that lists various syndromes with the number of Barr bodies – Note the all but one rule applies |
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Term
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Definition
| One Y-chromosome and more than one X-chromosome. All but one are Barr bodies |
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Term
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Definition
| One X-chromosome and no Y-chromosome. The X-is completely turned on. |
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Term
| Triplo-X or Poly-X female |
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Definition
| Has 3 (Triplo) or more (poly) X-chromosomes. All but 1 are Barr bodies. |
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Term
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Definition
blended inheritance
red hair from father's wound in battle
birthmark where mother burned herself |
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Term
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Definition
| Preformationism - born as mini-adults |
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Term
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Definition
Segregation
Independent Assortment |
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Term
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Definition
double loop of DNA around histone proteins
beads on a string |
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Term
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Definition
| identical unless mutations |
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Term
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Definition
| Alternate forms of the same gene |
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Term
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Definition
| two alleles of the same form |
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Term
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Definition
| hybrids - one of each of 2 types of alleles |
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Term
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Definition
one functional allele
null mutation
dosage compensation - same # of x-linked transcripts for both |
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Term
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Definition
expressed when present
homozygous - 2 identical alleles |
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Term
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Definition
| masked by dominant, observed only in the homozygote state |
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Term
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Definition
| genetic makeup AA, Aa, or aa |
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Term
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Definition
physical characteristics
genotype + environmental factors |
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Term
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Definition
| identical in structure similar in content |
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Term
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Definition
| 2 sets of chromosomal types - two sets of 23 chromosomes or 23 homologous pairs in humans |
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Term
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Definition
| One set of chromosomes - could be a natural state for some species (yeast) or it could be the amount of genetic material present in gametes |
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Term
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Definition
| an abnormal state of haploid |
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Term
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Definition
G1 (cell grows) - S (DNA duplicates) - G2 (prepares for mitosis)
G=Growth
s=Synthesis (DNA duplicates)
DNA is packaged to prevent shearing forces from damaging the DNA. The packaging also helps in regulation of gene expression at this level. |
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Term
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Definition
2 each of H2A, H2B, H3, H4
DNA wrapped 2 times around histone octamer |
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Term
nucleosomes linked by?
creates chromatin |
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Definition
H1 histone - Linker DNA
nucleosome is 10nm |
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Term
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Definition
Prophase
Prometaphase
Metaphase
Anaphase
Telophase
cytokinesis |
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Term
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Definition
| Chromosomes condense and mitotic spindle forms |
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Term
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Definition
| Nuclear envelope disintegrates and spindle microtubules anchor to kinetochores. |
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Term
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Definition
| Chromosomes align on the spindle-assembly checkpoint (equator) |
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Term
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Definition
| Sister chromatids separate, becoming individual chromosomes that migrate toward spindle poles. |
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Term
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Definition
| Chromosomes arrive at spindle poles, the nuclear envelope re-forms, and the condensed chromosomes relax. |
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Term
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Definition
| Cytoplasm divides; cell wall forms in plant cells. |
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Term
| DNA packaging during cell division |
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Definition
| DNA is tightly packaged to prevent damage during chromosomal movements. |
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Term
| Packaging during Cell Division |
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Definition
step one: Solenoids - 6 nucleosomes/360 degree turn also known as the 30nm fiber
Step 2: Chromatid and Chromosome Formation
- Scaffolding proteins will lay down the foundation for chromsomes
- solenoids will complex with the scaffolding proteins forming chromatids
- Two sister chromatids are attached at their centromeres forming chromosomes |
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Term
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Definition
| 6 nucleosomes/360 degree turn also known as the 30nm fiber |
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Term
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Definition
| centrally located centromere |
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Term
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Definition
displaced centromere more towards the top of the chromsomes
short P arm to Q arm |
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Term
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Definition
Extremely short p-arm (top region) in relation to q-arm (bottom region of chromsome)
Humans have 5 pairs of acrocentric
EXTREMELY short |
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Term
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Definition
The centromere is just below telomere
NOT FOUND IN HUMANS, FOUND IN RODENTS |
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Term
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Definition
recessive inherited
dominant mutation - not transferred
P-arm mutation |
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Term
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Definition
| taking a gene from one organism and inserting it into a different organism |
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Term
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Definition
comes from mother - acts like prokaryote
mother's sister's children have same as yours |
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Term
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Definition
color on the X-chromosome
must be female of Klinefedter's Male XXY |
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Term
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Definition
| spread out genes to prevent mutations, regulate expression, etc. |
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Term
| rDNA on acrometric chromosomes |
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Definition
| during interphase, organize the nucleoli, could form nucleoli during interphase |
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Term
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Definition
looks for homozygous or heterozygous by mating with homozygous recessive.
If heterozygous subject, get 1:1 ratio of Dominant trait to Recessive trait |
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Term
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Definition
myconium present indicates virgin female
4 sets of chromosomes - 3 autosomal, 1 sex |
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Term
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Definition
| during prophase I of meiosis, pairing of homologous pairs forming synaptonemeal complex, leads to crossover and formation of chiasma |
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Term
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Definition
| during prophase to telophase stages of mitosis, meosis I and meiosis II. It is the movement of nuclear material or division of the nucleus. |
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Term
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Definition
| Secondary oocyte with unequal cytokinesis |
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Term
oogonia and spermatogonia
oogonium and spermatogonium |
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Definition
oogonium and spermatogonium undergo meosis to become primary oocyte and primary spermatocyte
primary oocyte and polar body undergo to get ovum (ootid) and polar bodies
secondary spermatocytes become spermatids and mature into sperm |
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Term
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Definition
| Mother of modern genetics - jumping genes |
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Term
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Definition
| homologous regions in X and Y chromosomes that allow them to form synaptonemeal complexes |
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Term
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Definition
| any allele that can cause the premature death of an organism. It can be due to a dominant or recessive allele. Death can occur at any stage of development from fertilization to relatively old age. |
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Term
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Definition
| the expression of one allele does not completely mask the expression of the second allele |
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Term
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Definition
| both alleles are completely expressed |
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Term
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Definition
| the degree to which individuals with a particular genotype demonstrate that genotype |
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Term
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Definition
| the number of individuals who have a particular genotype demonstrating that genotype |
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Term
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Definition
| many genes influence one characteristic |
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Term
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Definition
| one gene influences many characteristics |
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Term
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Definition
factors other than the immediate genes that regulate the expression of these genes
Temperature
Modifiers, enhancers, or silencers |
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Term
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Definition
| [n(n+1)]/2 = the number of possible genotypes |
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Term
| Restricted, Mallard, Dusky |
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Definition
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Term
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Definition
enzyme A - Enzyme B - Enzyme C to product
peppers - express 9:3:3:1 as different colors |
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allows you to determine if a phenotype is due to a mutation at one location or if multiple locations are involved.
drosophila clot X safranin eyes = red eyes (both produce brown eyes if homozygous recessive, |
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daughterless mutation dada cannot produce daughters, DA da crossed to dada father will have both sons and daughters in equal numbers
mother's genetic makeup influencing the offspring |
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| DNA binding matrix - ion exchange chromatography (binds DNA) |
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RNase A, glucose & isotonic salts
RNase cleaves any RNA present and ensures a pure extraction of DNA, free from RNA impurities.
Could also use ethanol |
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Lysing solution. NaOH (denatures DNA) and SDS (denatures proteins)
SDS (sodium dodecyl sulfate) - SDS is an anionic detergent which disrupts cell membrane and destabilizes all hydrophobic interactions holding macromolecules in their native form. |
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neutralization buffer - plasmid comes back together perfectly...Genomic DNA hybridizes incorrectly
Precipitates the SDS |
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| Cell debris and genomic DNA - discarded |
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