If allowed to self fertilize will always produce progeny of the same type.
A 2:1:1 ratio indicates what?
A cross between 2 hybrids (2Aa:1AA:1aa)
Mendel's laws:
First law, the Law of Segregation
Second Law, the Law of Independent assortment
Mendel's First law, the Law of Segregation:
Alternative versions of genes account for variations in inherited characters. (concept of alleles)
For each characteristic, an organism inherits two alleles (one per parent)
The dominant allele, is fully expressed in the organism's appearance; the recessive allele, has no noticeable effect on the organism's appearance.
The two alleles for each characteristic segregate during gamete production
Mendel's Second law, the Law of Independent Assortment:
One gene's inheritance is not
affected by that of another
A nucleotide is composed of what:
Sugar (ribose / deoxyribose).
Nitrogenous bases (purines & pyrimidines).
Phosphate group (PO4).
What are the two types of nitrogenous bases and how many atoms do they have?
Purine 9 atoms.
Pyrimidne 6 atoms.
What are the purine bases of DNA?
Adenine
Guanine
What are the pyrimidine bases of DNA?
Cytosine
Tyhosine
'/What are the purine bases of RNA?
Adenine
Guanine
What are the pyrimidine bases of RNA?
Cytosine
Uracil
What group is on the 5' and, on the 3' end of a DNA strand?
Phosphate group (PO4) is on 5' end.
Hydroxcyl group (OH) is on 3' end.
Define oligomer
Short single-stranded nucleic acid fragments
What criteria can distinquish between DNA & RNA?
The sugar bases, DNA contains deoxyribose and RNA contains ribose.
How does DNA act as a genetic information carrier?
Can store large amounts of information.
Can be replicated faithfully.
Define trinucleotide:
Quiz choose the correct letter: What criteria can you use to distinguish DNA from RNA?
E) The sugar base (ribose vs. deoxyribose).
What is the chemical nature of the transforming agent (Strep. pneumo)?
Resistant to organic solvent and proteases (not a protein).
Resistant to ribonuclease (not RNA).
Sensitive to deoxyribonuclease (DNA).
What are the 3 types of DNA sructures and which was discovered first?
A, B, Z
B was discovered first
What are Chargaff's rules?
The content of pyrimidines and purines are always roughly equal.
When competing with giants...
Giants start small
Giants make mistakes too
Define denaturing (DNA melting):
Process of seperating DNA strands by heating them.
Define melting temperature (Tm):
The temperature at which DNA strands are half denatured.
Define annealing (renaturing):
Process of reuniting seperated DNA strands.
Define DNA hybridization:
Process of annealing a DNA strand with a complimentary or nearly complimentary RNA strand or DNA strand from a different origin.
What effect does G/C content have on denaturing and annealing?
Increased G/C content requires more heat to denature.
Increased G/C content requires less time to anneal.
Quiz True or False: The G/C and A/T base pairings are important for?
Holding the two DNA strands together __.
Replicating DNA __.
The temperatures required for denaturing and renaturing of two DNA strands __.
Keeping the DNA helix with the same width __.
The length of the DNA molecule __.
Whether a DNA should be in A form or B form __.
T_ Holding the two DNA strands together.
T_ Replicating DNA.
T_ The temperatures required for denaturing and renaturing of two DNA strands.
T_ Keeping the DNA helix with the same width.
T_ The length of the DNA molecule.
F_ Whether a DNA should be in A form or B form.
What are the purposes of molecular cloning?
Separate a gene from the other genes
Amplification of modified forms of genetic materials
Manipulation of a piece of DNA for further experiments
Which vectors can be used as DNA carriers?
Plasmids
Bacteriophage/phage
Cosmids
Bacterial artificial chromosome (BAC)
Yeast artificial chromosome (YAC) Virus
Importance of restriction endonucleases?
Host enzymes that prevent the invasion of foreign DNA, by cutting them up (restriction).
Cut within the DNA, rather than chewing away from the ends (endonucleases).
Recognize a specific DNA sequence (4-12bp) which is twofold symmetry and cut both DNA strands.
Some make staggered cuts (sticky ends).
Some make even cuts (blunt ends).
How do you set up a restriction endonuclease reaction?
Choose the right enzyme.
DNA free of contaminants such as phenol, chloroform, alcohol, EDTA, detergents, or excessive salts.
Reaction buffer.
Incubation temperature.
Stopping a reaction (heat inactivation).
What conditions contribute to Star activity?
High glycerol concentration [>5% v/v].
High enzyme concentration.
Low ionic strength [<25 mM].
High pH [>pH 8.0].
Presence of organic solvents [DMSO, ethanol…].
Substitution of Mg++ with other divalent cations [Mn++.…].
What conditions inhibit Star activity?
Use as few enzyme as possible to get a complete digestion.
Make sure the reaction is free of any organic solvents such as alcohols.
Raise the ionic strength of the reaction buffer.
Lower the pH of the reaction buffer to pH 7.0.
Use Mg++ as the divalent cation.
What are the details of each cloning vector?
Plasmid
Phage
Coxmids
Bacterial Artificial Chromosomes (BAC)
Yeast Artificial Chromosomes (YAC)
Plasmid: Extrachromosomal circular DNA molecule that autonomously replicates inside the bacterial cell; cloning limit: 0.1-10 kb.
Phage: Derivatives of bacteriophage lambda; linear DNA molecules; cloning limit: 8-20 kb.
Coxmids: Extrachromosomal circular DNA molecule that combines features of plasmids and phage; cloning limit - 35-50 kb.
Bacterial Artificial Chromosomes (BAC): Based on bacterial mini-F plasmids. cloning limit: 75-300 kb.
Yeast Artificial Chromosomes (YAC): Artificial chromosome that contains telomeres, origin of replication, a yeast centromere, and a selectable marker for identification in yeast cells; cloning limit: 100-1000 kb.
What is the function of DNA ligase?
Covalently link 2 DNA strands (blunt/ sticky, adhesive end ligation).
Quiz True or False:
Hybridization is favored by a higher concentration of complimentary sequences __.
Hybridization is favored by raising temperature __.
Hybridization is favored by raising salt concentration __.
Blund end ligation is more efficient than sticky end ligation __.
A phage plaque contains many different phage particles __.
A plasmid DNA can carry a minimal 8 kb long DNA __.
T_Hybridization is favored by a higher concentration of complimentary sequences.
F_Hybridization is favored by raising temperature.
T_Hybridization is favored by raising salt concentration.
F_Blunt end ligation is more efficient than sticky end ligation.
F_A phage plaque contains many different phage particles.
F_A plasmid DNA can carry a minimal 8 kb long DNA.
Quiz Choose the Letter: Antibiotic resistant genes in plasmid are important for?
C) selected growth of a particular plasmid carrying this gene
Quiz Choose the Letter: The following substrates are best for Restriction Endonucleases?
A) double stranded DNA
Quiz Choose the Letter: cDNA is easier to manipulate than mRNA because?
a) It is shorter than mRNA,
b) It is more stable than RNA
c) It is easier to make than RNA,
d) It has higher G+C% than RNA
Quiz Choose the Letter: The following enzyme is required for PCR reactions