Lecture Slides Flashcards
A _______ is an organism’s complete set of DNA, including all of its genes. Each ________ contains all of the info needed to build and maintain that organism.
Genome, genome
In humans, a copy of the entire genome, more than 3 billion DNA base pairs, is contained in all ________ that have a nucleus.
cells
How many feet of DNA strand are compacted in Cell?
6ft.
______ reads DNA to make protien!
RNA
When genes are tightly bound, it keeps them from being _______or read.
expressed
So, DNA is _______ in all cells of an individual & _________ different across individuals (except identical twins).
same; different
If DNA is ______ in all cells, why do we have different kinds of cells?
If identical twins have identical DNA, how do they end up _______?
identical; differing
Environment
__________ is the study of: all the cases where the genetic code alone isn’t enough to describe what’s happening-there must be something else going on as well
Epigenetics; genes and DNA don’t define us completely
Waddington’s (1948)The Epigenetic Landscape claims that there is no simple correspondence between ________&________. Rather, there is an interaction of genes with one another and with the ___________.
The marble on the hill: at the top________, and rolling downhill- increased, irreversible ___________.
Genes & outcome; with environment; undifferentiated cell; differentiation. (downward because cant roll back up! it’s also nature! hill represent SES, Family, and School etc.)
“Marble Location: Top of the Hill”
Zygote
The first stage of development- ________ can form every cell in body + placenta
totipotent
Down the hill= _______
Blastocyst
Cell differentiation begins: _________(Placenta) & ___________
Trophoblasts; inner cell mass
Inner cell mass contains embryonic stem cells (ESCs) that are ________ (Can form every cell in body except ________)
pluripotent; placenta
Sperm contains ______ chromosomes and egg contains _____ chromosomes.
23; 23
cells know what to do through ______________ based on their location.
chemical messaging
Research has revealed ESCs can be maintained in ______ state so there is a hope for therapies. Differentiated cells can be _________________.
(e.g. a skin cell can “roll back uphill” to become a ________)
undifferentiated; reprogrammed back into stem cell; stem cell
In 2006, Takahashi and Yamanaka inserted ____ genes into differentiated cells and they were reprogrammed (induced) to _________.
4; pluripotency
What are the 4 inserted genes doing in the iPS cell research?
They’re undoing epigenetic Modification
When you modify DNA you are altering whether or not a _________
gene is expressed
What are the two major classes of epigenetic modifications?
DNA Methylation & Histone Acetylation
What is DNA Methylation and what does it do?
Binds a methyl group to DNA (methyl sent down and attaches to DNA because of enzyme-external experiences). Begins a cascade of events that INTERFERE with gene expression. “SILENCING”
What is Histone Acetylation and what does it do?
Binds acetyl group to histone (protein) and begins cascade of events that ENHANCE gene expression. (relaxes chromatin structure and unwinds, genes now available to be read or turned on.
we still have the _____ genes but enzymes send different chemical groups that either turn on or off genes.
same
Gene “Switched on”
Active (open) chromatin; unmethylated cytosines; acetylated histones
Gene “Switched Off”
Silent (condensed) chromatin; Methylated cytosines; deacetylated histones
DNA methylated =
OFF & TIGHT
Acetylated Histones
ON & LOOSE (think loose ass)
When you reprogram cells you move cells ______ in epigenetic landscape.
up
In Takahashi & Yamanka study- the proteins expressed by inserted genes: _______ responsible for __________ and cell begins to ____________.
demethylate; pluripotency; dedifferentiate
Takahashi and Yamanka research revealed that epigenetic markers _______ be removed.
could
What are the long lasting effects of childhood trauma?
elevated cortisol levels in adults with traumatic childhoods
In response to hippocampus: _______ releases ____ and arginine vaspressin, which stimulate _______ to release _______ which stimulates _______ to release ______ which circulate back to hippocampus and tells you to “calm down”.
Hypothalamus; CRH; Pituitary; ACTH; Cortisol
What are effects of excess cortisol to the body?
EVERYTHING
Maternal behavior of rats ________ the genes expression; less nurtured rats have ______ marks hiding the genes.
sculpted; more
RATS: offspring to low licking mothers have ______ cortisol. So its not the genes of the mother, its the ________ of the mother.
More; behavior
In healthy cells, ther is a balance between activity of _________ genes and __________ suppressor genes.
oncogenic (switch off); Tumor (associated with prevention, switch on)
Cells become cancerous thru 2 processes: ________ to these genes (difficult to treat without destroying tissue) and _________ to these genes (_____ of ______ suppressor genes= decreased activity leads to invasive cancer; treatment with drugs that inhibit ________ responsible for methylation)
mutations; with epigenetic modifications; methylation of tumor; enzymes
Normal cell =
oncogene turned off & tummor-suppressor switched on!
unmethylated agouti gene in rats = ____________
and methylated agouti gene in rats = brown coat, normal weight
yellow coat; obese
The epigenetic modifications of rats of the Agouti Gene were handed down to offspring but, _________ diet for pregnant yellow females = brown, healthy pups and _____ reduces________ of agouti but with diet of methyl rich + BPA food the pups are brown and healthy
methyl rich; BPA; methylation (tightens agouti gene so silences it)
In the brains of mice induced to experience “chronic social defeat stress” the ___________ gene is silenced: indicating depression.
emotion processing
with antidepressants there is evidence of histone acetylation, so the emotion processing gene is ___________.
activated
Genotypes ______ determine how we live
dont
Phenotypic plasticity allows us to cope with the variation that the ________ presents.
environment
________ offers an explanation for how plasticity develops.
Epigenetics
Epigonetic modifications come from the _________.
enviornment
