Unit 4 (DNA, RNA, & Central Dogma) Flashcards
Define enzyme
A macromolecule serving as a catalyst, a chemical agent that increases the rate of a reaction without being consumed by the reaction. Most enzymes are proteins.
Define activation energy (Ea)
The amount of energy that reactants must absorb before a chemical reaction will start; also called free energy of activation
When a substrate enters the enzyme’s ____ ____, the enzyme changes shape and enfolds the substrate or alternatively termed ____ fit.
active site
induced
What type of bonds hold the substrates in the active site, and while being held, what complex is this in the Cycle of an Enzyme?
weak hydrogen ionic bonds
enzyme-substrate complex
Enzymes are said to be _____ when all enzyme active sites are engaged, and the only way to increase enzyme product formation rate is to increase the number of that enzyme. True or false?
saturated
true
Define enzyme-product complex
Part of the enzyme when substrates are converted to products while still held in the enzyme active site
***Increased spacing between nucleosomes correlates with increased gene expression. (Like a dance floor; lots of space = more area to express yourself)
Review
Identify mutation
Silent mutation - change in a base (nucleotide) but doesn’t change the final amino acid chain
What mutation is a change in a single base/nucleotide, and causes a premature stop codon?
Is this protein usually functional?
Nonsense mutation
No
____ mutation is a change in one base pair/nucleotide which causes a single amino acid to be changed in the resulting protein.
This mutation is the cause of the disease, sickle cell anemia.
Missense mutation
(Remember - Missense/mistake change)
____ and ____ are additions or losses of one or more nucleotide pairs in a gene.
These are ____ mutations because the genetic code can no longer be read as a triplet, and causes a ____ in the reading frame.
Insertion, deletion
frameshift
shift
(Can be “frameshift missense” and “frameshift nonsense” as well)
____ ____ ____ is used when there is damage to a single nucleotide.
DNA ____ ____ find and remove the damaged base, ____ ____ adds a new nucleotide, and ____ seals the final nick.
Base excision repair
repair enzymes
DNA polymerase
ligase
Damage to a small number of bases, caused by ____ ____ for example, is repaired by ____ ____ ____.
What are the repair steps?
UV light
nucleotide excision repair
This type of DNA repair is similar to nucleotide excision repair except that it recognizes and removes mistakes made during ____ ____.
What do DNA polymerase and ligase do?
Mismatch repair
DNA replication
