Solutions & Dilutions & Chromatography
Transformation & Sterile Technique
Gel electrophoresis & PCR
Central Dogma of Biology
Acids & Bases
100
What is molarity?
Molarity (M) = mole/ Liter
100
What is a restriction enzyme?
An enzyme that cuts DNA at a specifc sequence
100
What is the overall electric charge of DNA? In gel electrophoresis, toward which electrode will DNA move?
DNA is negatively charged. DNA will "run towards the red" positive electrode.
100
What is the central dogma of biology?
the flow of genetic information from DNA to RNA to protein
100
What is the pH range for acids?
1 to <7
200
If you want to make 2L of a 6M NaCl solution, how many grams of NaCl do you need? Na molar mass: 22.9898 g/mol Cl molar mass: 35.453 g/mol
6M NaCl = 6 mol NaCl / 1L 2L solution * (6 mol NaCl / 1L) = 12 mol NaCl molar mass of NaCl = 22.9898g/mol + 35.453g/mol = 58.4428 g/mol NaCl 12 mol NaCl * (58.4428 g/mol) = 701 g NaCl
200
What are the 2 kinds of restriction enzymes?
Blunt-end and sticky-end cutting restriction enzymes
200
If you start with 10 pieces of DNA, how many copies of DNA will you have after 5 rounds of PCR?
10 * (2^5) = 320 copies of DNA
200
What is transcription?
the process when a particular segment of DNA is copied into RNA (mRNA) by the enzyme RNA polymerase
200
What is the pH range for bases?
>7 to 14
300
If you have a stock solution of 6M NaOH and you want to make 500mL of 1M NaOH, how much of the 6M NaOH do you need? How much water do you need?
C1*V1 = C2*V2 C1 = 6M NaOH, V1 = ? C2 = 1M NaOH, V2 = 500mL V2 = 500mL * (1L/1000mL) = 0.5L (6M NaOH) * V1 = (1M NaOH) * (0.5L) V1 = 0.0833L of 6M NaOH water needed= 0.5Ltotal solution - 0.0833L NaOH = 0.4166L water
300
What is transformation?
The genetic alteration of a cell resulting from the direct uptake and incorporation of genetic material from outside the cell
300
What in the structure of DNA contributes to the majority of it's overall electric charge?
negatively charged phosphate groups in the sugar-phosphate backbone
300
What is translation?
The synthesis of proteins directed by an mRNA template. During translation amino acids are linked together to form a polypeptide chain which will later be folded into a protein. tRNA, a specialized RNA molecule carries an amino acid at one end and has a triplet of nucleotides, an anticodon, at the other end. The anticodon of a tRNA molecule can basepair, i.e form chemical bonds, with the mRNA's three letter codon.Thus the tRNA acts as the translator between mRNA and protein by bringing the specific amino acid coded for by the mRNA codon to the ribosome to add to the growing polypeptide chain.
300
What is the pH for a neutral solution?
7
400
What does TLC stand for and what is it useful for?
Thin Layer Chromatography is useful for separating molecules based on polarity from a mixture.
400
What is sterile (asceptic) technique?
A set of specific practices and procedures used to prevent the introduction of unwanted organisms into an environment.
400
What are the 3 steps of one cycle of PCR?
1. Denature (separate the 2 complementary strands of DNA at ~95 degrees C) 2. Anneal primers (attach primers to the complementary sequence of DNA at ~55 degrees C) 3. Extend (add nucleotides to the growing complementary DNA strands at ~75 degrees C)
400
What is a codon?
The information contained in the nucleotide sequence of the mRNA is read as three letter words (triplets), called codons. Each word stands for one amino acid.
400
If you measure the pH of a solution to be 4, what is the concentration of H+ ions in that solution? Is this solution acidic, basic, or neutral?
pH = -log[H+] [H+] = 10 ^(-pH) = 10 ^(-4) M Acidic
500
If you have a mixture of molecules of 2 different sizes, what technique should you use to separate them?
size-exclusion chromatography
500
What is a recombinant plasmid?
A recombinant plasmid is a plasmid that contains a foreign fragment of DNA in it.
500
In what direction does DNA replication occur? Why is there directionality?
5' -> 3' Because the enzyme DNA polymerase can only add a new nucleotide to an existing 3' end of DNA (it needs a free hydroxyl group)
500
If a sequence of DNA is: 5' - ACGATTCGCGTACGA - 3' What is the sequence of the corresponding mRNA? What is the sequence of the first corresponding tRNA anti-codon?
mRNA: 3' - UGCUAAGCGCAUGCU - 5' tRNA: 5' - ACG - 3'
500
If a solution has a pH of 8, what is the pOH of the solution?
pKw = pH + pOH pKw = 14 by definition We are given pH = 8 14 = 8 + pOH Solve for pOH pOH = 6
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