Flashcards in AP bio chapt 9 Deck (62):
DNA and its role in heredity: Needed to show the three following...
Evidence: DNA in the Nucleus
Nuclein; Precipitation of DNA from White blood cell (WBC)
In 1868, Miescher:
Was extracting DNA from puss in wounds
Evidence: Doubles in the cell cycle
Evidence: Twice as much in diploid cells
Further flow cytometry
Evidence: DNA is transmitted
Virus that attacks bacteria
Elucidating the structure of DNA: Why so key to know DNA structure? 2 important q's:
1. How is DNA replicated between cell division
Elucidating the structure of DNA: Crucial piece of evidence...
Crucial piece of evidence came from x-ray diffraction. Roseland Franklin
Double Helix: 4 key features:
1. Double stranded.
DNA from many species exhibited the certain regularities.
Structure Confers Function: 4
1. Storage of genetic information
Structure confers function: 1. Storage of genetic information
We are looking at the nucleotide sequence: summarize by saying "Variations = differences"
Structure confers function: 2. Precise replication during cell division
complementary base pairing. This was huge as we now have a way of copying
Structure confers function: 3. Susceptibility to mutations
Change in sequence
Structure confers function: 4. Expression of coded information as phenotypes
DNA --> RNA --> Proteins
DNA replication is semiconservative:
They realized there must be a copying mechanism. Each parental strand is a template.
DNA replication is semiconservative: 2 general steps:
1. DNA unwound
DNA replication is semiconservative: Ways to read the DNA.
The parent strand is read in a 3' to 5' manner. Nucleotides are added 5' to 3' direction.
Nucleotides added to new strand of DNA on 3' end:
DYKNOW NOV 9 slide 5 look up and understand
Origin of Replication
- Many ORi's: 10,000-40,000 bases
DNA Replication and Primase: A ___ ___ is needed
Starter Strand is needed: primer
DNA Replication and Primase: Most of time is:
DNA Replication and Primase: _____ to template DNA
DNA Replication and Primase: Enzyme used called _______: definition
Primase: Able to add RNA nucleotides to the enzymatic strand to our replication complex getting started
DNA Replication and Primase: Primer of RNA is eventually ______ and the whole strand is ____
DNA Replication and Primase: _____ ______ catalyzes the addition of nucleotides to the growing strand
15 ID'd DNA polymerase in humans
DNA Replication - Strand
Function is to replace the primer.
DNA Replication: Each ____ ____ requires...
Each Okazaki Fragment requires its own primer, synthesized by the primase.
DNA Replication: ____ ____ adds nucleotides to the...
DNA polymerase adds nucleotieds to the 3' end until reaching the primer of the previous fragment.
DNA Replication: A _____ ___ ______ then ______ ____ _____ with DNA.
A different DNA polymerase then replaces the primer with DNA.
DNA Replication: The Final ________ linkage between fragments...
The Final phosphodiester linkage between fragments is catalzyed by DNA ligase.
The Terminal Primer: Okazaki fragments are
Okazaki fragments are added to RNA primers to replicate the lagging strand
The Terminal Primer: When the last primer is removed...
When the last primer is removed no DNA synthesis occurs because there is no 3' end to extend -- a single-stranded bit of DNA is left at each end.
The terminal primer: These are cut after...
These are cut after replication and the chromosome is slightly shortened after each cell division
The area that gets chopped off at the end of cell division put a cap on the end to stabilize
The little lights at the end of the chromosome are called telomeres. They are highly repetitive.
The older we get the shorter our _____ get.
Can add an RNA template with ______
PCR -Polymerase Chain Reaction: Materials needed:
PCR Figure 9: 15
DNA Repair Mechanisms
Two flavors of this. The top one is occurring while replication is taking place.
Genetic mutations: Somatic
All but germ line DNA
Genetic Mutations: Germline
Mutations can occur in:
Either coding or non-coding regions.
One nucleotide is different/single nucleotide change
Point Mutations: list:
Point mutations: silent
Silent: No effect
Point mutations: Loss of function
loss of function of either the gene, or protein, or mRNA is non-functional
Point mutations: Gain-of-Function
when you have a single nucleotide change, the mutation causes new protein function. If dominant inheritance; "always on"
Point mutations: Conditional
Restrictive - mutant phenotype being expressed
Point mutations: slide 12 dyknow nov 12
affect many many genes. Multiple changes
Chromosomal mutations: Deletion
Removal of a chromosome segment.
Chromosomal mutations: Duplication
when we have homologous chromosome break and swap DNA incorrectly.
Chromosomal mutations: Inversion
Chromosomal mutations: Translocation
Non-homologous chromosomes exchange segments.