Cell Bio Lab Exam Flashcards
Look at microscope and identify Ocular Lens, Objective Lens, Stage, Clips, Course Focus Knob, Find Focus Knob, and Diaphragm
When examining objects under a microscope, always begin your observations with the _______ power lens, usually ____x.
Lowest, 4
When using a microscope, only use the coarse focus knob with the _______ power objective lens
Lowest
How to do find the total magnification of the microscope?
Multiplying the magnification of the ocular lens (10x) by magnification of objective lens
What are the three shapes of bacteria
Cocci, Bacillus, and Spirillum
What is principle behind a detergent-based cell lysis solution?
The detergent dissolves the phospholipids of cell membranes by forming water soluble complexes with them
What is cell lysate?
The contents of dissolved membranes, cellular proteins, DNA, and other contents
What was the purpose of the gatorade when collecting cheek cells?
The sodium in the gatorade ensured that cells would not break open and release their DNA before being collected because it is compatible with the osmotic environment
What is DNA insoluble in?
Ethanol
Why was ethanol used to extract the DNA from the Cell Lysate in Lab 2?
DNA is insoluble in Ethanol, allowing it to precipitate out of the lysate and become visible as stringy fibers
What two bases are Purines?
Adenine and Guanine
What two bases are Pyrimidines?
Cytosine and Guanine?
Why do Pyrimidines and Purines come together in DNA?
Only three rings can fit between the two sugar-phosphate chains so they combine with each other
How is DNA coiled so tightly to fit inside the nucleus of a cell?
It is tightly bound around histones which then create loop-like nucleosomes, and then the nucleosomes coil and condense to become chromatins
What is Agarose isolated from?
Seaweed
How will DNA travel through a gel during Gel Electrophoresis?
The smallest DNA fragments will move furthest while larger fragments move much less. DNA is negatively charged so when the electrical current comes the DNA will move toward the positive side of the apparatus
Does the percentage of Agarose in Gel matter?
Yes, if there is a greater percentage the DNA will have a more difficult time moving than a low percentage which is why we used 0.8% in our lab
In Gel Electrophoresis, the higher the voltage, the ________ the gel runs and DNA migrates
Faster
Gel Electrophoresis:
Black end is _______
Red end is _________
Negative
Positive
Restriction enzymes are ______ that are produced by bacteria to precent or restrict invasion by foreign DNA
Proteins
A nuclease is any enzyme that cuts the phosphodiester bonds of the DNA ________ while an Endonuclease is an enzyme that cuts somewhere ______ the DNA molecule
Backbone
Within
Restriction enzymes appear to be made solely by _________
Prokaryotes
What is a DNA Palindrome?
A sequence in which the top strand is ready 5’ to 3’ and the same for the bottom but other way
It is a restriction site of 4-6 base paires
What are sticky ends and what enzyme is responsible for creating them?
The cutting of DNA but not directly across from each other on the molecule leaving “tails”
EcoRI and HindIII produce Sticky Ends
What are Blunt ends and what enzyme is responsible for creating them?
The cutting of two strands of DNA directly across from each other producing a straight end
SmaI produces blunt ends
What enzyme puts back together DNA fragments that are generated from restriction digestion?
DNA Ligase
What is the definition of Recombinant DNA
DNA molecule that has been assembled from different starting molecules
What is the definition of DNA Splicing?
The cutting and linking of DNA molecules
What is the point of DNA Splicing?
To remove a functional DNA fragment from the chromosome of one organism and combine it with the DNA of another organism to study how the gene works
What is the sugar found in then backbone of DNA?
Deoxyribose
Where does the restriction enzyme EcoRI cut?
G and A
An important feature of restriction enzymes is that each enzyme only recognizes a specific palindrome and cuts only at the specific ________
sequence
What is a bacteriophage?
A bacterium-invading virus
Why do restriction enzymes work best at 37 Degrees Celsius?
They were isolated from bacteria that live inside warm-blooded animals and therefore are used to that temp
What are plasmids?
Small, circular DNA molecules that can reside in cells
Why can a cells DNA copy plasmids?
Plasmids contain an origin of replication allowing DNA to begin synthesizing a new molecule here
In the plasmid lab, after the bacteria absorb the plasmid DNA, they __________ the new antibiotic resistance genes
Express
What is a probe?
A special DNA “hook”
usually a form of DNA called single-stranded DNA
What is southern blotting?
Transferring DNA fragments from a gel directly to a membrane so the pattern of the fragments would be preserved
What is Souther Hybridization Analysis?
The combination of restriction analysis, transfer to a membrane, and hybridization to a probe
What is genetic transformation?
it is the change caused by genes and involves the insertion of a gene into an organism to change the traits
What is genetic transformation used for?
in agriculture it can be used to add genes that code for frost, pest, or spoilage resistance
What is gene therapy?
The genetic transformation of a sick person’s cells with healthy copies of the defective gene that caused the disease
What is the source of the Green Fluorescent Protein Gene?
A Bioluminescent Jellyfish
Following the transformation procedure in the GFP lab, what trait will the bacteria exhibit?
They will fluoresce
What is the recent occurrence of bacterial resistance to antibiotics due to?
The transmission of plasmids
The gene for GFP can be switched on in transformed cells by adding the sugar ____________ to the cells’ nutrient medium
Arabinose
To genetically transform an entire organism, you must insert a new gene into _____ cell in the organism
Every
The pGLO plasmid carries the GFP gene that codes for the green fluorescent proteins and a gene that codes for a protein that gives the bacteria resistance to an antibiotic
What plate from the pGLO lab glowed?
LB/Amp/Ara/+pGLO plate
All of the shit to make it glow
What four sites does the pGLO Plasmid have?
Ampicillin Resistance site allows pGLO plasmid to resist ampicillin
Arabinose Promoter allows expression of GFP if arabinose is present
Origin of Replication allows for reproduction of plasmid
Green Fluorescent Protein
What was the purpose of the chromatography column in the pGLO lab?
The chromatography column contains hydrophobic beads and high salt buffers helped to keep the hydrophobia proteins stuck to the beads while all other shit drained through
What did the binding buffer do in the GFP lab?
Allowed the GFP to remain with the chromatography column
What did the elution buffer in the GFP lab do?
It contained less salt and allowed the hydrophobic GFP to no longer stick to the beads and instead drip down the column
What is another word for Sanger Sequencing?
Chain termination
How does Sanger Sequencing (Chain Termination) work?
DNA is added to four tubes, DNTP is added, ddNTP is added, and DNA polyermase is added to synthesize the strand with incorporated ddNTPs that will stop the synthesis when one is added
This can then be run through gel electrophoresis
What is the difference between a deoxynucleotide and dideoxynucleotide?
Dideoxynucleotide lacks the 3’ OH group that is necessary for the phosphodiester bond to form
What is cycle sequencing ?
one tube that incorporates all necessary components that allows the termination event to be detected via wavelengths of light
What is DNA profiling?
The use of molecular genetic methods used to determine the genotype of a DNA sequence
What is the purpose of PCR
Polyermase Chain Reaction produces large amount of a specific piece of DNA from trace amounts of staring material
What are the requirements for PCR to occur?
One DNA template strand, DNA polymerase, 2 DNA Primers, and 4 Nucleotides, and Reaction Buffer
What are polymorphic sequences?
The less than 0.5% of the human genome that differs and can be used for DNA profiling
The DNA sequences that are used in forensic labs are non-coding regions that contain segments of _______________
Short Tandem Repeats
What is the Denaturation Process of PCR Amplicatiion
Heat is used to melt apart or denature the double stranded DNA template
What is the Annealing Process of PCR Amplification?
Sequences of DNA either upstream or downstream of target sequence are used to make primers that will serve as a start and stop point for amplification
What is the Extension Process of PCR Amplification?
DNA polymerase binds to primers and adds nucleotide and synthesizes new copies of the double stranded template
In our PCR lab, what was DNA polymerase isolated from to perform at temperatures of 52-94 degrees celsius
A thermophilic Bacterium
What are the three possible ways to create transgenic animals?
Pronuclear Microinjection
Retroviral Transformation
CRISPR Cas9 Transformation
What occurs in the the process of Pronuclear Microinjection?
Female mouse super ovulates breeds with male but embryo is collected and injected in nuclei before sperm nuclei fuse
Embryo transfer to a pseudopregnant girl then occurs
What occurs in the process of Retroviral Transformation?
The virus is incorporated into the cell’s genome and cell presents new genes
Bad because random insertion of the genome occurs so it may mess with the cells DNA
What occurs in the CRISPR Cas9 Transformation Process?
Use of guide RNA complementary sequence to insertion site
Pros involve picking exactly where you want your sequence to be in genome
This is targeted not random
Over thousands of years, each of the ________ major world crop plants has been extensively improved
15
What is Plant Biotechnology and what does it allow for?
An extension of traditional plant breeding that allows for transfer of only one gene
What is the difference between traditional plant breeding and plant biotechnology?
Traditional plant breeding involved the combination of multiple genes at once while Plant Biotechnology allowed for the combination of one desired gene
List three ways agricultural productivity is limited
Weeds, Pests, and Diseases
How does Glyphosphate work?
Blocks EPSPS and therefore does not allow plant to produce proteins , leading it to die
What would the Glyphosphate Resistant Gene do for crops?
Allow plant to be sprayed with chemical and no get harmed but weeds around would die
What is a problem with Glyphosphate?
Weeds become resistant to Round-up creating super weeds
How does Bt as an insecticide work?
The Cry protein in the Bt binds and creates pores in intestinal lining of insects causing death
Now a modified version of Cry gene can be placed within plants so when insects eat it they will die but humans will not
What is a problem with the development of insect resistance?
Other organisms such as Monarch Butterflies and unintentionally targeted
What occurs within papaya’s to withstand the ring spot virus?
Papaya’s are transformed with gene for coat protein of PRSV so that the gene from the pathogen is used in plant so that virus can bind to its receptors
What is Golden Rice?
The addition of three genes that synthesize beta-carotene being implemented into rice allowing for body to convert to vitamin A
What is Wheat transformation and how does it work?
Embyros from a stage are collected and bombarded with DNA coated gold particles
Cells that survive are grown and trait is seen
Agrobacterium Method
It naturally infect plants and acts like a fat tumor so scientists can hijack that and replace it with a gene of interest to get into the platns
How did antisense technology work to keep tomatoes from spoiling?
Antisense mRNA united with plants mRNA and inactivated it. No mRNA was produced and therefore no proteins were produced and no decay occured
What can be classified as an embryonic stem cell and what are they dubbed after that time period?
8 weeks post fertilization
Fetal cells and are totipotent
Adult stem cells are __________ and have been isolated from various organs in the body
multipotent
Why was Dolly the sheep named Dolly?
The cells used to create her were taken from the mammary gland of an adult
creation of dolly the sheep summary
Cells taken from mammary gland of adult
placed in culture
growing in G1 phase
Eggs were removed from oocyte donor and enucleated
Somatic cell and enucleated egg fused together
transfered to surragote
What was the first animal to go extinct twice?
Pyrenean Ibex
What is the difference between animal therapeutic cloning and reproductive cloning
Reproductive intent is to produce a new being
Therapeutic cloning provides stem cells
