Terms from Biology Videos Flashcards
DNA Polymerase
Enzyme that carries out DNA replication
Helicase
Breaks apart double stranded DNA
Primase
Creates RNA primer
Primer
Pairs with template strand to initiate DNA replication
Ligase
Joins molecules together to form one large molecule
Okazaki Fragment
Short, newly synthesized DNA fragments that are formed on the lagging strand
Leading Strand
Strand that is in the direction of the growing replication fork
Lagging Strand
Strand that is in the opposite direction of the growing replication fork
DNA is read in the __ to __ direction
3’ to 5’
DNA is synthesized in the __ to __ direction
5’ to 3’
Proto-oncogene
Normal cellular gene that regulates cell division and growth
Tumor Suppressor Gene
Genes preventing the proliferation of cancer in cells
What are the four reasons why proto-oncogenes can mutate into oncogenes?
- Missense mutation
- Gene amplifications
- Chromosomal translocations
- Viral integration
What are the three types of mutations?
- Chromosomal mutations
- Genome mutations
- Gene mutations
Silent Mutation
Base substitutions that do not alter the amino acid sequence of the polypeptide
Missense Mutation
Base substitutions in which an amino acid change does occur
Nonsense Mutation
Base substitutions that change a normal codon to a stop codon
Frameshift Mutation
Involving the addition or deletion of a number of nucleotides that is not divisible by three
PCR
A technology which allows us to amplify single or multiple copies of DNA pieces to make millions of copies of DNA sequences.
What components are required for PCR?
- DNA template
- Two primers
- Taq polymerase
- dNTPs
- Buffer solution
- Mg2+
- K+
What are the steps of PCR?
- Denaturation (heating)
- Annealing (binding)
- Elongation
DNA
Double stranded (sugar and phosphate sides) molecule that carries genetic information
Codominance
Situation in which two different alleles for a genetic trait are both expressed
Essentially, both alleles are expressed because they share dominance
Incomplete Dominance
Form of intermediate inheritance in which one allele for a specific trait is not completely expressed over its paired allele.
• Results in a third phenotype in which the expressed physical trait is a combination of the phenotypes of both alleles (like a red and white flower leading to a pink flower).
Pleiotropy
Phenomenon of one gene being responsible for or affecting more than one phenotypic characteristic.
Epistasis
When the expression of one gene is affected by the expression of one or more independently inherited genes
ex: people who are born with the albinism gene will have no pigmentation even if their genes for hair, skin, and eye color indicate they should have high levels of melanin
Mitosis
Process where a single cell divides into two identical daughter cells (cell division).
Meiosis
Specialized form of cell division that produces reproductive cells, such as plant and fungal spores, sperm and egg cells. Consists of meiosis I (reduction) and meiosis II (division)
Cell Growth Checkpoint
- Occurs toward end of G1 phase
- Makes sure cell is big enough and has made proper proteins for S phase
- Goes through resting period (G0 phase) if it does not meet criteria in order to divide
DNA Synthesis Checkpoint
- Occurs during synthesis (S) phase
* Makes sure DNA has been replicated correctly
Mitosis Checkpoint
- Occurs in mitosis (M) phase
- Makes sure mitosis is complete
- Rinse and repeat the cell cycle
