Genetics Flashcards
Hemoglobin
a protein that is used to carry and transport oxygen in the blood
Insulin
a protein that is secreted by beta cells and used to regulate glucose (blood sugar levels in the body)
Linus Pauling
protein guy that came up with the structure of proteins. He determined the structure and interactions of all proteins and antibodies
Frederick Griffith
scientist to first discover DNA in the world of protein
Virulent
very strong strain and will cause disease
Principle of transformation
The principle that explains the ability of nonvirulent bacteria to become virulent.
Non Virulent
very weak strain and does cause disease
Oswald Avery
bacteriologist that identified DNA as the substance responsible for genetic transformation
DNA
Deoxyribonucleic acid, molecule that carries genetic information for the development and functioning of an organism.
RNA
Ribonucleic acid, RNA has a similar structure to DNA but with key differences: the sugar in RNA is ribose, which includes an extra oxygen atom compared to the deoxyribose in DNA. Additionally, RNA contains uracil instead of thymine. These distinctions enable RNA to move freely within the cell and play a crucial role in protein synthesis.
RNAses
Enzymes that break down RNA
DNAses
Enzymes that break down DNA
Erwin Chargaff
looked at the structure of DNA and discovered nucleic acids
Adenine
Purine that bonds to Thymine
Thymine
Pyrimidine that bonds to Adenine
Guanine
Purine that bonds to Cytosine
Cytosine
Pyrimidine that bonds to Guanine
Chargaff’s Rule
A-T and C-G always in DNA
Rosalind Franklin
Franklin’s graduate student, Raymond Gosling, captured the now-famous “Photo 51,” an X-ray diffraction image that revealed the helical structure of DNA.
Name some of the contributions of Linus Pauling
Came up with structure of proteins and covalent bonds
Discovered the structure of hemoglobin’s
Study the structure and interaction of proteins and antibodies
Created the basis for proteins
Explain Frederick Griffith’s experiment and how did it contribute to the discovery of DNA?
Griffith performed an experiment with bacteria and mice. He took a rough strain and a smooth strain of diseases. One was a virulent strain, which contains bacteria that causes disease and the other was a non-virulent strain, which doesn’t cause disease. In the first half of the experiment, Griffith used both strains and inserted them into two separate rats. One rat who received the non virulent strain survived, and the rat who received the virulent strain died. In the second half of the experiment, he added heat, when he added heat to both strains, it killed the bacteria within them, so when they were injected into the rats they survived. Then he combined both strains with heat and put them in the same rat, the rat survived. In the last portion of the experiment, Griffith took the non virulent strain and added heat to the virulent, when he put both strains into the rat, it died. The reason that this happened is because the DNA of the virulent strain jumped into the non-virulent and changed its genetic makeup turning the non virulent into the virulent, making it lethal which killed the rat.
How did Frederick Griffith contribute?
Heat denaturized proteins in virulent strand, and proved the existence of Nucleic Acids
Explain the principle of transformation of Frederick Griffith
Process by which genetic material from one organism is taken up by another organism, leading to a change in its characteristics.
Explain Oswald Avery’s experiment and how did it contribute to the discovery of DNA?
Had an experiment where he put rough strain into two test tubes. Then used DNAse (protein that eats DNA) and RNAse (protein that eats RNA). When He put the RNAse in it created more bacteria because DNA can always create more RNA. When he put the DNAse in, it destroyed the DNA, meaning no bacteria was created. Through this experiment he proved that DNA is the basis of all life.
Explain Chargaff’s rule and how did it contribute to the discovery of DNA?
A-T and C-G are always in DNA structure and showed the structural makeup of DNA
Explain what is wrong with this structure of DNA that Linus Pauling drew?
It has 3 helix’s and nucleic acids do not behave like proteins.
Explain Rosalind Franklin’s picture and its importance to the discovery of DNA.
The image taken above shows a clear x-shaped pattern which revealed that DNA has a double helix structure made of two intertwined strands. Provided evidence on how DNA is built and how it carries genetic information.
Nucleic acids
molecules found in cells that store and transmit genetic material. The two types are DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA holds the instructions for building and maintaining an organism, while RNA helps carry out those instructions.
Ribose
oxygen present sugar molecule
Nucleotides
are the basic building blocks of nucleic acids. Each nucleotide is made up of three parts: a molecule sugar, phosphate group and a nitrogenous base (adenine, thymine, cytosine, and guanine).
Deoxyribose
no oxygen present sugar molecule
DNA
molecule that is held together in an non covalent manner by van der waals bonds
RNA
nucleic acid that carries out the instructions of DNA by making proteins and regulating gene activity.
Uracil
in DNA, uracil replaces thymine.
Supercoiling
how DNA can coil positively or negatively. The coiling can possibly break the structure
different forms of DNA
B-DNA
A-DNA
Z-DNA
B-DNA
normal version
A-DNA
supercoiled; clockwise
Z-DNA
messed up, more flat; counterclockwise
DS
Double stranded
Hairpin
protects the structure of RNA
SS
Single Stranded
Why are ATP and GTP not nucleotides?
ATP and GTP have nothing to do with DNA. They have too many phosphates and have everything to do with the formation of energy.
What is the function of phosphate in nucleic acids?
Portion of the DNA that provides structural support to the molecule.
List three differences between RNA and DNA.
DNA:
Deoxyribose
Two Helix
Numerous type of DNA
RNA
Ribose
One Helix
One type of RNA
Explain the antiparallel structure of DNA.
The antiparallel structure of DNA refers to the orientation of its two complementary strands, which run in opposite directions. Each strand of the DNA double helix has a directionality defined by its sugar-phosphate backbone, with one strand running from the 5’ (five-prime) end to the 3’ (three-prime) end, while the other runs in the reverse direction from 3’ to 5’.
Adenine will always pair up with?
Thymine in DNA and Uracil in RNA
Three different types of RNA
RNA Sequence (level 1)
RNA secondary structure (level 2)
RNA tertiary structure (level 3)
What does it mean RNA can form Hairpins and why?
an unpaired loop of messenger RNA (mRNA) that is created when an mRNA strand folds and forms base pairs with another section of the same strand.
What are the structures RNA can form?
RNA Sequence
RNA secondary structure
RNA tertiary structure
Hairpins are what level
level 2
Replication
process by which the genome’s DNA is copied in cells.
Polymerase
enzyme that is used to put together (writer)
Exonuclease
pulls nucleotides out of the structure of DNA (editor)
DNA Polymerase
enzymes that make the covalent bonds between the nucleotides (monomers) to form a new DNA strand (making a huge polymer).
DNA pol III
polymerase that is first (writer) and elongates primers (epsilon)
Topoisomerase
relaxes the DNA structure to give other proteins access
Ligase
glues backbone of new DNA strand together
DNA pol I
degrades the primers and fills the gaps of new strand (editor of DNA)
Leading strand
can be continuously built in the direction of the replication fork because the new strand is already in the 5’ to 3’ orientation.
Primase
enzyme that adds primers (first pieces of nucleotides that signals DNA polymerase where to land, DNA pol III)
Helicase
Breaks DNA into two halves (strands) for replication
Lagging strand
must be built in repetitive segments in the opposite direction of the replication fork because of the strand orientation.
SSB Proteins
Protein that holds onto single stranded DNA so it doesn’t destabilize, while replication is occurring
Okasaki fragments
gaps in the DNA
5’to 3’
leading strand
3’ to 5’
lagging strand
Origin of replication (ORC)
starting point for replication of DNA
Replication bubble
a structure that forms when a DNA double helix is opened up and separated into two strands, and then two Y-shaped replication forks are created within the bubble
Replication Fork
it’s the spot where the DNA is being unzipped to make a copy of each strand during DNA replication.
Transcription
process in which a strand of DNA is copied into an RNA molecule
RNA pol II
places and puts new nucleotides together on strand
RNA pol I
makes rRNA
RNA pol III
makes tRNA
Pre M-RNA
RNA molecule right after being copied from the DNA
M-RNA
RNA molecule that forms after a cap is attached to protect the message, introns are spliced (polishes and deletes the unnecessary information from draft message), and gets a poly AAA at the 3’ end which shows the length of message.
Promoter
sequence of DNA that binds RNA polymerase to initiate transcription
TATA BOX
The landing zone for the RNA pol II that promotes the initiation of transcription.
Terminator
a section of DNA that adds adenine nucleotides at the end of message and that terminates the process.
Spliceosome
RNA complex that identifies and edits introns out of a pre mRNA mole.
Exon
piece of gene that is coded
Intron
pieces of RNA with no relevant information
snRNP’s (snurps)
participate in pre-mRNA splicing by recognizing the critical sequence elements present in the introns, thereby forming active spliceosomes.
CDS
coding sequence
UTR
untranslated region in DNA that protects the message from being destroyed
Cap (Methylguanosine)
protects the message
Poly aaa Tail
makes the RNA molecule more stable and prevents its degradation
rRNA
ribosomal RNA and helps make peptide chains
tRNA
transference RNA, transports the amino acids to the ribosomes and attaches the peptide using the enzyme t-RNA synthetase.
Codon
codes for an amino acid
Amino acid
building blocks of proteins (assemble into peptide chains)
Aceptor stem
the amino acids that accept the message from the nucleic acids
Anticodon
codon on the tRNA
t-RNA synthase
enzyme that makes tRNA
Ribosome
proteins that are divided of two pieces (60s large and 40s small) and help put amino acids together
Subunit 60s large
in charge of assembling the polypeptides
Subunit 40 s small
in charge of reading mRNA
APE: protein assembly sites
A: tRNA lands and delivers Amino Acids
P: tRNA makes the peptide bond
E: exits ribosome
Marshall Nirenberg Genetic code
created a table to translate the 20 Amino acids
Ubiquitin
enzyme that makes ubiquitination- the disassembling and destroying of proteins so they can be recycled.
Antibiotics
used to kill bacteria or fungi, these usually disrupt transcription and/or translation of specific proteins.
What is the difference between a polymerase and a exonuclease?
Polymerase - puts the nucleotides in the structure
Exonuclease - takes out nucleotides in the structure
Name all the proteins involved in DNA replication and their function.
DNA polymerase and DNA primase to catalyze nucleoside triphosphate polymerization
DNA helicases and single-strand DNA-binding (SSB) proteins to help in opening the DNA helix so that it can be copied
DNA ligase and an enzyme that degrades RNA primers to seal together the discontinuously synthesized lagging-strand DNA fragments
DNA topoisomerases to help to relieve helical winding and DNA tangling problems.
For Replication. DNA uses what polymerase?
Poly III and Poly II
What is the function of splicing the pre-RNA?
Getting rid of introns
What causes Okasaki fragments?
discontinuous DNA replication on the lagging strand during DNA replication
What is the sequence that promotes transcription of a gene?
TATA box
What is the function of the UTR’s?
Protection the message of RNA from being destroyed
What is the function of the Poly AAA tail? Like an instruction manual.
Tells everything about the function, expiration date, and location for RNA.
How does the t-RNA change from secondary structure to tertiary structure?
formed by further folding of the secondary structure
What does the s in the subunit means?
Large 60s (faster) and small 40s (slower), sedimentation (s)
Which subunit interacts with the m-RNA, and which interacts with the amino acids?
This subunit is primarily responsible for binding to the mRNA and ensuring accurate codon-anticodon pairing between the mRNA and tRNA molecules, which determine the sequence of amino acids in the growing protein chain
How does the acronym APE help us understand the function of the ribosome?
Puts steps of how ribosome makes peptide chain in nymonic order
What is ubiquitination?
essential player in protein homeostasis, serving to rapidly remove unwanted or damaged proteins.
How do antibiotics disrupt Replication, transcription, and translation?
targeting essential processes in the cell
How do antibiotics know how to attack the pathogens in our body and not our
machinery?
Antibiotics work by affecting things that bacterial cells have but human cells do not. For example, human cells do not have cell walls, while many types of bacteria do.
Transcription
process of copying genetic information from DNA into a molecule called RNA
Translation
the process by which a cell makes proteins using the genetic information carried in messenger RNA (mRNA)
Bacteriophage
viruses that infect and replicate on in bacterial cells
Coronavirus
negative single stranded RNA virus, this is why its so easily transmitted
DS
Double Stranded
HIV
is a retrotranscriptase virus where the RNA must undergo reverse transcription into DNA to be integrated into the host cell’s genome.
SS
Single
Positive sense
a DNA strand whose nucleotide sequence matches the sequence of an RNA transcript that can be translated into amino acids
Negative Sense
equivalent to the template strand, whereas the positive-sense strand is the non-template strand whose nucleotide sequence is equivalent to the sequence of the mRNA transcript.
5’ to 3’
leading strand
Group 1/Class 1
Hepatitis B DSDNA
Adenovirus DS DNA
Herpes Simplex DSDNA
3’ to 5’
lagging strand
Group 2/Class 2
Parvovirus SSDNA
Group 3 / Class 3
Reovirus DS RNA
Rotavirus DS RNA
Group 5/Class 5
Influenza SS RNA
Covid SS RNA
Ebola SS RNA
Group 4/Class 4
Poliovirus SS RNA
Group 6/class 6
Retroviruses SS RNA
Retrotranscriptase
enzyme that turns RNA into DNA
Baltimore Scheme
a scheme for classifying viruses based in its genome type and replication strategy
Explain the Central Dogma of Molecular Biology
DNA -> RNA -> Protein
Dictates the DNA replicates, RNA gets transcribed, and RNA turns into proteins
Explain How viruses disrupt the Central Dogma of Molecular Biology?
Because they can replicate RNA and some can go backwards in the scheme.
Can proteins turn into RNA?
No
For polio viruses, why do they need to turn their SSRNA into SSRNA -?
It is because it needs a template to be able to create mRNA, so it can replicate itself
Origin Recognition Complex (ORC)
Found in Eukaryotes and it is the start of replication without it then it cannot be replicated.
What is a fundamental characteristic that makes viruses from group IV to be different from group VI?
Viruses from group VI can turn their RNA into DNA
How can HIV turn SSRNA + into SSDNA-?
They use retrotranscriptase and replicate a single strand of DNA
Chromosomal Recognition Complex (OriC)
Found in Prokaryotes and it is the start of replication and without it cannot be replicated.
DNA pol III
enzyme responsible for DNA replication in prokaryotes
DNA Pol Epsilon
key enzymes involved in the replication of eukaryotic DNA. It plays a crucial role in synthesizing the leading strand during DNA replication.
Spliceosome
RNA complex that identifies and edits introns out of a pre mRNA molecule
Intron
Extra material that needs to be taken out.
Histones
used to wrap the DNA to form nucleosomes
P arm
shorter arm of chromosome
Exon
Material that will be coded for and so needs to stay in the DNA.
Q arm
longer arm of chromosome
Centrosome
middle part of chromosome that holds it together
Plasmids
a small circular DNA molecule found in bacteria and some other microscopic organisms.
Mention 3 differences between Prokaryotes and Eukaryotes.
Prokaryotes lack a nucleus, while eukaryotes have a distinct nucleus containing their DNA.
Prokaryotes have no membrane-bound organelles, whereas eukaryotes have multiple organelles like mitochondria and endoplasmic reticulum.
Prokaryotes are smaller and simpler in structure compared to larger and more complex eukaryotic cells.
The difference between Orc (Eukaryotes) and Ori C (Prokaryotes)
Orc (Origin Recognition Complex) - A protein complex that binds to a specific DNA sequence (the origin of replication) to initiate DNA replication.
Oric - The specific DNA sequence on a bacterial chromosome where DNA replication starts, which is recognized by the Orc complex.
If we swap the ORC with Ori C would the eukaryote be able to replicate its DNA?
No, because the DNA polymerase will look for the orc or ori c and won’t find it, which will prevent it from being able to replicate its DNA
What happens if we eliminate the Ori C of prokaryotes?
No replication of DNA will occur
The different components of a chromosome:
The p arm is the short structure of the chromosome
The q arm is the long arm structure of the chromosome
The centromere is the constricted point of the chromosome
