Test 2-P8,P9,P10 Flashcards
How do cells replicate
-DNA get synthesis breaking the parent double helix into 2 strands and theres strand each get a new strand with complimaenty based attached to it. So now we have 2 daughter doubles helix each with one new strand and each with one new strand.
What is genes expression
Cell In Multicellar organizsm have all the genes to make all the proteins
Transcribing from DNA, and then translating intoprotein is call gene expression
Example-babies skin cell don’t make alot of kertin which the protein to make hair but how cell decide that gene get trasncibed or translates is gene expression
Gene changes due to eviroment, development, age
Lac Opera
A cell can regulate the production of enzymes
by feedback inhibition or by gene regulation
* One mechanism for control of gene expression
in bacteria is the operon model
-Pieces of DNA on bacterial chromosomes that makes decsion about am i going to make this thing or not make this thing and it not one gene it is several genes
How the operon works
- A cluster of functionally related genes can be
coordinately controlled by a single “on-off
switch” - The switch is a segment of DNA called an
operator, usually positioned within the
promoter - An operon is the entire stretch of DNA that
includes the operator, the promoter, and the
genes that they control
The operon can be switched off by a protein
repressor(always around made by something outside the operon) - The repressor prevents gene transcription by
binding to the operator and blocking RNA
polymerase - The repressor is the product of a separate
regulatory gene, located some distance from
the operon itself
By itself, the lac repressor (protein) is active
and switches the lac operon off
* A molecule called an inducer inactivates the
repressor to turn the lac operon on. Lactose
(carbohydrate) is the inducer for the lac
operon
* The idea is not to transcribe and translate
genes unless you can use them (it’s expensive)
Pro and Con for Virus is alive
Covid 19 life cycle
Virus is covered in a membrane. Has mRNA for its genome. Can use energy from cell it is invading to reproduce.Can (is) evolving.
Covid-RNA varius want to make copies of itslef, but converious have similar genome-gene sequences and nukber of gene speciflized for pathogensis-how to differentiate
-Covid Process-Attach itself to self through virus cell interaction to bine to a protein ACE2, then it get in the because membrane hids it gentic material,virus genome is in cell, finds a host called a ribsome,Ribosomes take sequences viral RNA and tranlsates it protein, protein is the means to express genes, more of viral RNA, the faster the cell can be taken over
-Covid encode geen to complete its life cycle but also is the way it sends a message out to the cell to make more of its genes
Conlclsion-Alot of protein in cells from the virus or ones the virus has manipulated.End of viral lifcycle, it sends it potein to partiuclar places in the cell where protein are concentrated and new virus particles are made
Lac operon
b-galactosidase Degrades Lactose in to galatose and glucose using hydrosis/water because it cant use lactose diretly for energy but can use gluscose
The lac operon and contains genes that code
for enzymes used in the hydrolysis and
metabolism of lactose
Lactose present
int he absences of lactose the lac repressor bind to the operor and prevent the RNA polymeriese from moving to trsncibes the DNA into MRNA
-the machine is off
-RNA only binds to the promoter if it had to have CAMP/CRP-Present when no glusose
Lactose not present
RNA Connect to promoter, lactose, the inducer take repressor off operor by changing its shape, machine is on to transcribed lac Z, Y, A at a slow rate and translated to make protein to make enzymes to break down lactose into glusocse and galatose
When latose all gone the repressor goes back to its shape and bind to the operor again to shut it off
permeate allows to suck up lactose when it is around
if glucose and lactose around
Machine wont turn on
CRP protein sense the glucose change by sensing Camp response(signaling molecule_
-Glucose high, camp low
-Lac operon only deals with lactose
Group question 8-Lac operon when glusose and lactose around(Draw)
Draw
Eukaryotic Epigenetic
Gene Regulation
Eukaryotic gene expression is more complex than in
prokaryotes:
Transcription and translation are physically
separated.
Regulation can occur at many levels.
1st level begins with control of access to the DNA –
epigenetic regulation – and occurs before
transcription begins.
Transcription factors are proteins that control the
transcripton of genetic information from DNA to
RNA
Eukaryotic Epigenetic
Gene Regulation
*
Promoter and
Transcription machinery
This is an example of why control
of transcription is more
complicated in Eukaryotes.
* Lots of proteins involved-all of
which can affect transcription
* The control elements can be
physically far away from the part
of the gene that turns into protein
* Mutations that affect the length of
the DNA in that loop can affect
transcription
DNA bending protein changes the shape of DNA
and properly orients enhancer region.
What is alive and do virus do it
Exist as one or more cells(NO)
* Use and synthesize genetic information
to reproduce(Yes)
* Descend from other beings and are the
products of evolution(Yes)
* Produce molecules from environmental
substrates(Virus don’t do themselves but code in other cells to do this)
* Harvest energy and use it to perform
functions(Use Energy from the cells they effect not of their own and but doesn’t perfrom its own fucntion and doesn’t convert its own energy)
* Regulate their internal environment(Yes, but to rudementry extent)
Virus
usually really small
-HIV virus has an envelope/membrance around it, Capsid had RNA but not a nucleus
-All cell have DNA but virus can have DNA or RNA
-HIV has spike protein onto he outside which binds to human cells
-Virus genome is smaller tha a cell(3.1 billion base pairs), HIVless than 10,000 bp to cripple the
human immune system (human
genome is 310,000X bigger)
Cell
Covid Test
Rapid covid- test detects a protein made
by the virus(nucleocapsidprotein-not the
spike associate with mrna inside the virus).Faster,cheaper, lessaccurate
(more chance of false
negative).-(Tell us about virus that may not be infectous)(No variation/no much in nucleocapsidprotein in the variants)
PCR covid test detects mRNA (spike) from
virus.Slower, more accurate*,More
sensitive Spike proteins(Variation of covid is the spike protein-coming up against antibodies in population, the virus make new version of spike protein to get around it)
Vaccines(Ask)
MRNA vaccines, their is code to make the spike in the vaccine and now to make antibodies against this spike, not MRNA from the whole virus that why you dont get covid
Benfits-you can make it fast(6 Weeks, other vaccines take 2 or 3 years)
Bosttser-half of orignals and hald of new spike BA5
-Spike is how virus get in the cell, vaccines help cell make anitbodies to stop the virus
Are virus alive Alive
1) All (cells) viruses come from
preexisting (cells) viruses.
2) (cells)
Viruses maintain internal
environments that differ from their
external environments.
3) (cell)
Virus structure defines (cell) virus
function.
4) (cells) Viruses
communicate with other (cells)
viruses.
Covid-Why some people are asymptomatic
htpothesis :Covid virus expose someone thn other because some expose to virus similar, so they have antibodies against it
Pfizer lower does or MRNA than Moderna(MRNA Vaccine)
Johnson and Johnson(DNA molecules incorpated by cells that turns into MRNA for Spike protien)
Draw Mitocondria
Outer membrane (s)
Inner membrane
Matrix
Intermembrane space
Thylakoid
Grana
Stroma
ONE LINE= ONE MEMBRANE
Submit it to Group Exercise #9 folder- all names (first
and last)- 1 pdf file
Draw Chlorplast
Outer membrane (s)
Inner membrane
Matrix
Intermembrane space
Thylakoid
Grana
Stroma
ONE LINE= ONE MEMBRANE
Submit it to Group Exercise #9 folder- all names (first
and last)- 1 pdf file
