Unit 6 Flashcards
DNA
Double stranded, contains genetic material and instruction
RNA
single stranded, used in the process of replicating DNA
mRNA
RNA that is created by using the DNA strands as a template and this gets processed through the ribosome where the protein is created
tRNA
transfer RNA that carries specific amino acids to the ribosome for protein creation
rRNA
ribosomal RNA, one of the most common types of RNA
Prokaryote circular chromosome vs Eukaryotic linear chromosome
one circular chromosome for prokaryotes that allows for more rapid replication but multiple linear chromosomes for eukaryotes which allows for more complex information to be stored
DNA Plasmid
circular DNA that is double stranded and different from the chromosomal DNA of the cell, can occur in both prokaryotes and eukaryotes
in bacteria, the plasmid codes for resistance to antibiotics
Purine
a part that is used to compose RNA and DNA
A and G
Pyrimidines
a part that is used to compose RNA and DNA
T, U, and C
DNA Replication
process through which a DNA strand splits and creates two new strands from the original strand
5’ to 3’
both strands of DNA have a 5’ and 3’ end and they both go in different directions in an antiparallel fashion
DNA Replication is semiconservative
this basically just means that each strand of DNA has an old strand and a new one too
Template strand
DNA strand which is the template for the RNA which is creating the transcript
Non template strand
the strand from which the RNA is not creating the transcript from
Sense strand
the strand that is identical to the mRNA that is created during transcription
this is also known as the coding strand, the mRNA is NOT using this strand as a template to create itself
Antisense strand
the strand that is complementary to the mRNA that is created during transcription
it is also known as the template strand, as the mRNA is using this strand to form itself
Antiparralel
parallel but going in different directions
Helicase
in charge of untwisting the double helix
Topoisomerase
in charge of breaking/altering and rejoining the DNA strands as the helicase unzips in order to relieve tension in the strand
Replication fork
basically just the part where the DNA has been split up into two parts in a Y shape
Replication bubble
the small part of the DNA that has become unwound to carryout the DNA replication process
DNA polymerase
it adds nucleotides to the strands after they are split apart in order to replicate them.
RNA Primer
a short RNA section used as a place for DNA polymerase to bind so that it can initiate DNA replication (it can’t start without anything else already there)
Continuous or leading strand
the strand that gets created in the direction that the replication fork is going in
Discontinuous or lagging strand
the strand that gets created in broken pieces (okazaki fragments) in the opposite direction that the replication fork is going in.
Ligase
puts the DNA fragments together (the separated pieces on the lagging strand)
Transcription
this is when the DNA is read as a reference and a RNA is created that is complementary to the strand
termination
the ending of protein synthesis when the new protein is released
Ribosome
the site for protein synthesis
Codon
groups of three nucleotides that order a specific amino acid
Anticodon
this is the key to the codons, it lies on tRNA which carries the amino acids to the mRNA strands in order to help create the protein… the anticodon correlates to the codon on the mRNA and this helps them bring the right amino acid that is needed
Central dogma of molecular biology
basically genetic information is a one way street
ex.
DNA -> RNA -> Protein
or
RNA -> Protein
RNA polymerase
in charge of putting ribonucleotides into an mRNA chain during transcription
Gene
information that codes for certain traits
Poly-A tail
the group of adenine that are at the end of the 3’ side for mRNA
protects from degradation, helps with travel from nucleus to cytoplasm, + helps with binding to ribosome
GTP cap
a kind of guanine on the 5’ side of the mRNA
helps to bind mRNA to the ribosome
Introns
doesn’t stay in the mRNA after transcription
Exons
it does stay in the RNA and has information about coding proteins
Alternative splicing
this is when introns (and sometimes exons) are slide out of the mRNA strand.
Spliceosome
this splices the RNA and prompts the removal of the introns
Translation
the mRNA is read and amino acids are created based on the code provided by it
Initiation
at the initiation site, RNA polymerase binds to the promoter region which tells the polymerase where to start transcribing
elongation
the codons in the mRNA get read and the amino acid chain gets longer
Start codon
group of three nucleotides that starts translation
Stop codon
group of three nucleotides that stops translation
polypeptide chain/protein
a string of amino acids together than make up proteins
Retrovirus
a virus that has RNA and can use reverse transcriptase to change its RNA to DNA once inside a host
Reverse transcriptase
enzyme coded by retrovirus and uses this to turn their RNA into double stranded DNA so that the virus can mimic the host
Epigenetics
the way in which environmental and external factors can affect the expression of genes
Chromatin (euchromatin vs heterochromatin)
Chromatin is made of DNA and histones and they tightly package the DNA into a chromosome form to fit in the nucleus
Heterochromatin is highly condensed and shows inactive gene state vs euchromatin is less condensed and shows active genes
Histone Protein
gives structural support to chromosomes, dna wraps around the histones to make compact chromosome
Methylation
adding methyl groups, and is a chemical alteration of the DNA that can be passed down
Acetylation
adds acetyl groups to the histones and can affect the structure of the DNA, can turn genes on
Transcription factors
regulates transcription and controls the rate as well
Enhancers and Repressors
enhancers are small sections of DNA that activators can be bound to increase likelihood of transcription for a specific section
repressors when bound to its operators can reduce chances of transcription for a certain section
Activators
a protein that binds to enhancers in order to increase transcription
Operon
groups of genes on the same strand in a genome that are co-regulated and have related functions
Lac operon
structural genes that order for proteins to be made that can digest lactose
Trp operon
code for enzymes that are needed to create tryptophan
Cell differentiation
this is the process through which a cell becomes specialized
Promoter
the section of the DNA where the RNA polymerase binds to
Differential gene expression
expression of different genes by cells even if they have the same genetic composition
microRNA
used to control gene expression and helps the cell control how many and what kind of proteins are made
Mutation
a change in the DNA or RNA sequence from the original sequence of nucleotides
Phenotype
the physical display of a trait
Positive mutation
mutations that cause positive impacts like a mutation that protects the organism from developing heart disease or diabetes
negative mutation
a mutation that hurts the survival of the organism like cystic fibrosis or sickle cell anemia
Point mutation
this is when only one nucleotide changes
Nonsense mutation
a change in the DNA that makes a protein terminate before it should have
Insertion
this is when nucleotides are added/injected into a sequence
Deletion
when nucleotides or groups of nucleotides are removed from the sequence
Frameshift mutation
when the insertion or deletion is not a multiple of three and causes a shift in the reading frame for the codons
Mutations are the primary source of genetic variation
the main way in which evolution and genetic diversity comes to exist in our world is because of random mutations
Triploidy
when an organism has 3 sets of chromosomes in its cells instead of the usual two
Polyploidy
when an organism has more than the two normal sets of chromosomes
Horizontal gene transfer
transfer of genetic material between organisms that aren’t related to each other, main way for bacteria to get new genetic material
Conjugation
through physical contact, usually through a plasmid, bacteria directly transfer their genetic material
Transduction
DNA is moved from one bacteria to another by a virus
Transformation
bacteria takes DNA that is floating around near it
Gel electrophoresis
a process to separate nucleic acids and proteins by size
PCR
polymerase chain reaction - technique used to make million and billions of copies of certain parts of DNA sequences
Bacterial transformation
when bacteria takes foreign DNA into itself and is able to incorporate it
DNA sequencing
technique used to find the exact bases that are in DNA strands
Genetically modified organisms
organisms whose fenes have been artificially changed
