Bacterial enzymes that recognize foreign/viral DNA and cuts them into fragments - form of protection
Cut only a specific sequences usually palindromic sequences (sequence forwards = sequence backwards)
Bacterial DNA is protected by methylation (addition of -CH3 groups)
A Vector is a segment of DNA used to transfer a desired sequence into another cell. Often, the vector is a
bacterial DNA sequence such as a Plasmid
A vector is always a plasmid. But a plasmid is not always vector.
Technique used to ID target fragments of known DNA.
Electrophoresis to spread out pieces according to size
Blot it onto a membrane such as nitrocellulose
Add radioactive probe made from DNA or RNA
Visualize with radiographic film
Technique used to ID target fragments of known RNA.
Procedure is the same as southern blots
Detects particular protein with anti-bodies in a mixture of proteins
Restriction fragment length polymorphism (RFLP)
IDs individuals and not specific genes.
DNA of different individuals have different restriction sites and varying distances between restriction sites. After fragmenting the DNA with endonuclease, a band pattern that is unique to the individual is revealed (southern blot). Better known as DNA fingerprinting.
What are the stop codons?
UAA, UAG, and UGA
How can you calculate all the possible codons?
There are 4 different nucleotides and 3 possible positions for those nucleotides.
Thus, 43 = 64 possible nucleotides
A polypeptide contains 100 amino acids. How many possible amino acid sequences are there for this polypeptide?
There are 20 possible amino acids and 100 positions.
20100 = possible sequences.
What is a degenerative code?
There is more than one series of nucleotide sequences that code for an amino acid.
How are amino acids unambiguous?
Any series of nucleotides codes for ONLY one amino acid.
5' end attaches to small subunit of RNA and the tRNA-anticodon brings methionine (start codon) to P-site. The large subunit joins and translation begins.
Polypeptide its elongated, tRNA with corresponding amino acid attaches at the A-site (aminoacyl). - This step requires 2 GTP
C-terminus of Met attaches to the N-terminus of the following AA at the A site in a dehydration reaction.
Translocation( requires GTP): ribosome shifts 3 nucleotides along the mRNA toward the 3' end and the tRNA that carried Met moves to the E-site and exits the ribosome.
Polypeptide synthesis stops when a stop codon is reached at the A-site. Release factors add water to the A-site and release the polypeptide from the tRNA and ribosome.
Further, the ribosome breaks into large and small subunits and awaits another round of translation.
Sugars, lipids, or phosphates may be added to the amino acids
Polypeptide may be cleaved in one or more places
Separate polypeptides may join and form quaternary structures
Body cell or non sex cell, undergoes mitosis, diploid, and identical to parent cell
Sex cells, undergoes mitosis, meiosis, haploid, not identical to parent cell, and brings a variety of genetic information
DNA fragment of one chromosome breaks free and attaches to a homologous chromosome
When a part of chromosome breaks off or when a portion is lost during homologous recombination and/or cross over events
Segment of DNA from one chromosome is inserted into another chromosome
Orientation of DNA on the chromosome is reversed
Genes that stimulate normal growth in human cells
Converted proto-oncogenes via mutagens (UV radiation, chemicals, or random mutations) that cause cancer
Mutagen that can cause cancer
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