DNA Flashcards
The amino acids that correspond to three nucleotide codons of mRNA?
Genetic code
The strand of DNA that is not used to transcribe mRNA; this strand is identical to the mRNA except that T nucleotides in the DNA are replaced by U nucleotides in the mRNA
Non-template strand
The enzyme that catalyzes the joining of DNA fragments together
DNA ligase
A form of RNA that carries the nucleotide sequence code for a protein sequence that is translated into a polypeptide sequence
mRNA
The molecule shape of DNA in which two strands a nucleotides wind around each other in a spiral shape
Double helix
Bond between the sugar and phosphate group that builds the backbone of DNA
Phosphodiester bond
Connects the nitrogenous bases according to base pair rules : A-T, G-C, holding DNA into its 3D shape
Hydrogen bond
Method used to amplify many copies of the DNA fragments in the process of DNA fingerprinting
Polymerase chain reaction
Enzyme from Thermos Aquaticus, a thermophile, responsible for building the complementary strands of DNA during PCR; heat stable
Taq polymerase
Molecular scissors that can cut DNA at specific locations
Restriction enzymes
A short nucleic acid sequence that provides a starting point for DNA synthesis
Primer
Specific equipment responsible for DNA sequencing, cloning, generation probes, quantification of DNA and more
Thermocycler
The process of removing the DNA from the nucleus and the rest of the cellular material
DNA extraction
The four nitrogenous bases of DNA
Adenine thyamine cytosine guanine (A,T,C,G)
A simple machine that makes a small containers of liquid
Vortex
If I have eight DNA nucleotides, how many DNA bases do I have? And how many base pairs?
Each nucleotide-regardless of whether it’s a DNA or RNA nucleotide-has a phosphate, sugar, and a base.
(So 8 DNA nucleotides would have 8 bases. DNA bases pair in twos which equal 4 DNA base pairs)
What would be the complementary DNA bases for this strand?-
If one strand of DNA has the base pairs: A, T, T, G, A, C… can you complete what the complimentary DNA bases would be for the other DNA strand?
Remember the base pairing rules for DNA and the popular mnemonic “apple to tree” (A-T) and car to garage” (C-G). Answer: T, A, A, C, T, G
In a process known as transcription, a complimentary RNA strand called Messenger RNA has to compliment the DNA. So if we still had the original portion of DNA: A,T,T,G,A,C… What would be the complementary RNA bases?
RNA= AU “apples under”, CG “car garage” Answer: U,A,A,C,U,G
True or false: bases are read in 3’s, so a codon is how these bases will be read. (E.g, AUG, CCA, GUC, etc.)
True
True or false: by reading a code on chart, you can determine the amino acids that will be brought in by the tRNAs. You can also determine the sequence of amino acids that make up a protein.
True
True or false: The most common ways to read a chart are the rectangular codon chart and the circular codon charts
True
True or false: codons are on the mRNA. The start mRNA is AUG.
True
True or false: The tRNA anticodon will be UAC if the mRNA is AUG (because of the base pairing rule)
True
True or false: when using a codon chart it is the mRNA that we look at.
True
True or false: In a rectangular codon chart, The left side of the chart is: first base, The top part is: second base, and the right side is: third base
True
True or false: The code mRNA for AUG stands for methionine.
True
True or false: methionine is commonly the starting amino acid for many polypeptide chains as AUG is a start codon.
True
True or false: when an mRNA reaches a STOP- It means it doesn’t code for an amino acid And it’s the end of a sequence for a polypeptide.
True
Who discovered relationships between DNA bases; A to T and G to C (the base pair rule)?
Erwin Chargaff
Who took X-ray crystallography DNA image number 51?
Rosalind Franklin, Raymond Gosling, Maurice Wilkins
Long, double helix, deoxyribose, nucleus only-guanine, cytozine, adamine, thymine=
DNA Structure
Short, single strand, ribose, nucleus or cytoplasm- juanine, cytozine, adenine, uracil
RNA structure
5’ prime carbon - 3’ prime carbon (DNA runs anti parallel)
Anti-parallel configuration
The three parts of a nucleotide
Neutrogynous base, pentose sugar, phosphate group
What are the two nitrogenous bases
Purines and pyrimidines
Double ring, guanine, adenine
Purine
Single ring, thiamine (uracell in RNA), cytosine
Pyrimidine
Forms between pento sugars and phosphate groups; creates backbone of DNA
Phosphodiester bonds
Nucleotides attached two ways
Phosphodiester bonds and hydrogen bonds
Form between complimentary nitrogenous base pairs; holds two DNA strands together; forms rungs of a ladder
Hydrogen bonds
DNA: A to T, G to C
RNA: A to U, G to C
Chargoffs base pairing rule
Occurs in “S” synthesis phase of interphase; 1) double helix unwinds and unzips (replication fork), 2) each parent strand of double helix serves as a template, 3) free floating DNA nucleotides are assembled according to base pair rules to form complementary daughter strand 5’-3’
DNA replication basics
What are the 5 bonds
Ionic, covalent (polar and nonpolar), hydrogen, peptide, phosphodiester
Forms between pentose sugars and phosphate groups; creates backbone of DNA
Phosphodiester bond
True or false: The Human genome contains 3 billion base pairs
True
True or false: DNA replication results in two double stranded DNA molecules identical to original DNA
True
Discontinuous synthesis on the lagging strand produces DNA segments
Okazaki fragment
Discontinuous synthesis occurs 5’-3’ (away from replication fork) and runs out of DNA
Lagging strand
True or false: leading and lagging strands are daughter strands
True
Searches DNA for initiation site
DNA promoter
Region from promoter to Terminator
Coding sequence
Detects termination signal and releases primary mRNA
Terminator
What are the 3 stages of transcription
DNA promoter, coding sequence, terminator
Sequence of three nucleotides in DNA or RNA that codes for specific amino acids; signals beginning or end of protein synthesis
Codon
Keratin, muscles, enzymes, hemoglobin, antibodies, JETRAT (junction, enzyme, transport, recognition, attachment, transduction), ribosomes, hair and nails
Types of proteins
Assemble according to base pair rules: U-A, C-A
Free floating RNA nucleotides
Bond between amino acids of one amino acid and the carboxyl group of another
Peptide bonds
True or false: There are more variation at RNA sequences
True
Original DNA is split and each half is used as template to assemble new
Semi-conservative replication
What are the five enzymes
DNA helicase, RNA primase, DNA polymerase 3, DNA polymerase 1, DNA ligase
Unwinds and unzips double helix of DNA; two parent strands
DNA helicases
Creates RNA primer; attaches to end
RNA primase
Builds daughter strand in 5’-3’ direction; requires primer, must move in 5’-3’ direction; proofreads as it builds daughter strand
DNA polymerase 3
Degrades RNA primer and replicates it with DNA nucleotide
DNA polymerase 1
Seals gaps in DNA backbone on lagging strand
DNA ligase
5’-3’
Lagging strand
3’-5’
Leading strand
Two stages of making proteins
Transcriptions and translation
Flow of information from gene or DNA nucleotide sequence to protein production (DNA- RNA to protein)
Central dogma of biology
Happens in nucleus; short (1) strand segment of original DNA; creates complimentary messenger RNA strand
Transcription DNA to RNA
True or false: translation is RNA to protein that creates a polypeptide
True
Enzyme that controls transcription; assigns promoter; unwinds Helix and detects termination
RNA polymerase
Transcribes messenger and DNA and carries out ribosome for protein synthesis
mRNA processing
Needs to get ready and dressed
Pre mRNA
Three steps of mRNA processing
5’ cap, 3’ cap and splicing
Coding regions
Exons
Non-coding regions
Introns
Mature RNA
Splicing
True or false: translation process occurs in ribosomes
True
3 RNA types
mRNA, tRNA, rRNA
Carries genetic code information from DNA to ribosome
mRNA (messenger)
Three nucleotides in DNA are RNA that correspond to specific amino acids; signal start or end of protein synthesis
Codon
True or false: There are 64 codons
True
Transports amino acids to ribosomes
tRNA (transfer)
Complementary to mRNA; found on bottom of transfer RNA
Anticodons
Where amino acids attach- “shuttle”
Amino acid attachment site (AAA site)
Forms ribosome with protein; polypeptide is built; has large and small subunits; A acceptor site, P peptide site, E exit site
rRNA (ribosomal)
What are the 3 tRNA building sites
A- acceptor, P- peptide, E- exit
Considered redundant but not ambiguous; very specific, universal to all life on Earth
Genetic code
3 types of RNA
Messenger (mRNA), transfer (tRNA), ribosomal (rRNA)
What are the 3 stages of transcription
Initiation, elongation, termination
First step; RNA polymerase binds to DNA and promoter; initiating unwinding of double helix to access template strand (promoter)
Initiation transcription
RNA polymerase moves a long DNA template strand; adding nucleotides to RNA by base pairing rules with DNA sequence; (coding sequence)
Elongation transcription
Final stage; RNA polymerase reaches termination sequence on DNA; causing RNA to detach and transcription process ends (Terminator)
Termination transcription
3 stages of translation?
Initiation, elongation, termination
Starting translation by assembling ribosome, mRNA and first tRNA molecule at start codon (start codon)
Initiation translation
Sequential addition of amino acids to growing polypeptide chain as ribosome moves along mRNA (mRNA codone)
Elongation translation
Final stage where polypeptide chain is released from ribosome when a stop codon is reached (stop codon releasing factor)
Termination translation
What are the different categories of mutations you can see in DNA (genetic changes)?
Point mutations, frame shift, chromosomal
Insertions or deletions that shift reading frame
Frame shift mutations
Large scale changes like deletions, duplications, inversions and translocations
Chromosomal mutations
Study of how environmental factors and behaviors can alter gene function without changing DNA sequence; changes can: affect how a body reads DNA sequences
Epigenetics
Effects how body reads DNA sequences; impact production of protein in cells; influence risk of disease; passed from parents to children
Changes in Epigenetics
Diet, exercise, sleep, smoking, alcohol, stress,, toxin exposure (pollution, cigarette smoke), chemicals (BPA, lead), RX
Changes in epigenetics that are caused by these
True or false: Epigenetics can be reversible and are different from genetic changes
True
What does CRISPR stand for?
Clustered, regularly, interspace, short, palindromic, repeats
Genetic sequence found in bacteria that acts as defense mechanism against viruses; scientists have adapted this system to create a powerful tool for gene editing in the lab
CRISPR
DNA sequence that read the same forwards and backwards
Palindromic
What are the three types of stem cells?
Totipotent, pluripotent, multipotent
Derived from early embryo and have potential to develop into any cell type in the body
Embryonic stem cell
Found in various tissues throughout the body; can differ into limited range of cell type specific to their tissue origin
Adult stem cells
Adult cells reprogram to behave like embryonic stem cells, allowing them to differentiate into various cell types
Induced pluripotent stem cell
What are the three base substitutions/point mutations?
Silent, nonsense, missense mutations
What are the two frameshift mutations?
Insertions and deletions
True or false: an insertion or deletion of one or two bases is generally worse than an insertion or deletion of 3, 6 or 9 bases because it can shift the reading frame of the genetic message causing major impact.
True
What is an example of a missense mutation?
Sickle cell anemia
True or false: most mutations result from unrepared DNA polymerase errors during DNA replication (spontaneous mutations)
True
True or false: non-ionizing radiation (UV light), results in thymine dimmers, which lead to skin cancer.
True
True or false: for every second exposed to the sun, a skin cell accumulates 50 to 100 thymine dimmers
True
True or false: Gene expression takes place differently in prokaryotes and eukaryotes
True
True or false: prokaryotes have OPERONS
True
Functionally related genes group together on chromosome, switched on or off together
OPERON
Dissaccharide made of glucose and galactose
LAC= lactose
Bacteria can use lactose for energy; glucose is favorite energy source when both glucose and lactose are present; enzymes to digest lactose are only needed when lactose is present (positive control) and glucose is low
LAC OPERON
The production of enzymes that break down lactose
LAC OPERON
When the DNA is uncoiled and loosened from nucleosomes to bind transcription factors
Epigenetic level
When the RNA is transcribed
Transcriptional level
When the RNA is processed and exported to the cytoplasm after it is transcribed
Post transcriptional level
When tRNA is translated into protein
Translational level
After the protein has been made
Post translational level
True or false: eukaryotes don’t have operons
True
True or false: in eukaryotic gene expression, functionally related genes are not necessarily grouped spatially
True
True or false: In eukaryotic gene expression, coordinated expression is achieved by multiple similar control regions associated with functionally related genes
True
True or false: Eukaryotic gene expression, coordinate control of genes via similar control elements, rather than operons
True
A few specific methods for Eukaryotic gene expressions:
Chromatin modifications- (histone acetylation and DNA methylation); DNA control sequences (enhancers in silencers); regulator proteins (activators and repressors); transcription factors; alternative splicing of mRNA; degradation of mRNA; blockage of translation; proteasomes
Non-genetic influences on gene expression or phenotype changes without genotype changes
Epi genetics
True or false: maternal exposure to famine in early pregnancy increases the child’s risk of coronary heart disease, obesity and schizophrenia as an adult
True
True or false: all the information needed to build a new individual is encoded in the DNA sequence of the bases ATGC
True
Part of a DNA base sequence that codes for a specific protein
Gene
More primitive organisms, no nucleus, transcription and translation occurs simultaneously and regulation primarily at transcription level, archaebacteria and eubacteria
Prokaryote
Membrane-bound organelles (specialize in function-nucleus, mitochondria, chloroplast), transcription occurs first in nucleus then translation occurs in the cytoplasm, many levels regulation, protist, fungi, plants and animals
Eukaryot es
True or false: only prokaryotes have operons
True
True or false: coordinated expression is achieved by multiple similar control regions associated with functionally related genes
True
True or false: epigenetics can be changed by environment and lifestyle. These can affect gene expression for you and generations of your offspring
True
True or false: nucleosomes can slide along DNA. When nucleosomes are condensed (top), from methylation of DNA, transcription factors cannot bind and gene expression is (turned off).
True
True or false: when the nucleosomes are spaced far apart (bottom), from acetylation of histones, the DNA is exposed. Transcription factors can bind, allowing gene expression to occur. (Turns on)
True
True or false: cAMP levels increase only when glucose levels are low
True
Red blood cells
Erythrocytes
White blood cells
Leukocytes
Platelets
Thrombocytes
Protein that transports oxygen to all parts of the body
Hemoglobin
The transparent, yellowish fluid portion of blood
Plasma
Type of shock that results from significant blood loss
Hypovolemic shock
Proteins on the surface of B cells that are secreted into the blood due to exposure to an antigen
Antibodies
Universal blood donor
O negative
Universal recipient
Type O, A B positive
When red blood cells with A or B antigens mixed with anti-a or anti-B antibodies and cause red blood cell clumping
Agglutinate
