Flashcards in Neuroscience Deck (101)
What is prophase?
when the nuclear envelope breaks down and chromosomes start to be pushed around, pairs of homologous chromosomes form special bonds with each other
What is metaphase?
homologous chromosomes align at middle of cell; random alignments
What is an allele?
- They are “flavours” of genes that arise from mutations
- Also inherited by offspring
- They arise from mutations
- Functional transporter = dominant (ex: W)
- Defective transporter = recessive (ex: w)
What is a totipotent cell?
can become any of the 200 types of cells in the body, ultimate stem cell
What is regulating gene expression?
Turning a gene or a set of genes on or off
What is a heat map?
Graphical representation of data where the individual values contained in a matrix are represented as colours
- Aid in comparison of very complex data
- In general, a heat map displays relative abundance
- Used to correlate gene expression as a function of:
Location in the body (cell type)
What is a pluripotent cell?
Can form many types of cells within the same lineage
What is unipotent?
Can divide to produce more skin cells
What are the two major types of stem cells?
- Forms all the cells of you
- Trophoblast forms the placenta
- Tissue specific, not totipotent
- Hematopoietic stem cells (blood cells)
- Epithelial and epidermal stem cells (skin)
Explain the promise of stem cell research
- Identify drug targets and test potential therapeutics
- Study cell differentiation
- Understanding prevention and treatment of birth defects
How do you clone an organism?
• To clone an organism, it is not enough for the DNA to be identical
• All the necessary information in the DNA must be unlocked
What is differentiation?
Cells decrease in potential as they grow- the fate the cells is already locked in
Cloning is achieved through the process of what?
Explain the idea that information can be unlocked in G0
A method to unlock inaccessible information in DNA
Forensic DNA analysis focuses on what?
On the differences between individuals and “Variable regions” at specific locations throughout the genome tend to differ between individuals
What type of variability does forensic DNA focus on?
Short Tandem Repeats (STRs)
- An STR can have different numbers of repeats
What is a polymerase chain reaction?
Allow fabrication of millions of copies of molecules
STRs are amplified using what?
- The PCR primers attach to DNA sequences on either side of the repeats
- These regions do not vary between individuals
- The same primers can amplify the repeat region in any individual
Everyone inherits how many copies of STR?
Two- one from mom and one from dad
Forensic DNA analysis uses a standard set of what?
- The human genome contains thousands of STR markers
- For forensic investigation, the FBI has chosen 13 of the most reliable STRs, plus a marker called AMEL, which detects gender
- Using a standard set of markers allows information to be shared at the local state and federal level
Explain the evolution of DNA sequencing methods
1980s: Sequencing technology was labour intensive and used hazardous radioactive chemicals
1990s: More automated steps- sample preparation, sequence reading, etc.
- Additional improvements over the years cut cost and increased speed, allowing the HGP to finish under budget and ahead of schedule
Today: next generation sequencing technology
- faster and cheaper
Next step: the $1,000 genome
- The goal: sequence a human genome for $1,000 by 2014
Next generation sequencing technologies are very close to reaching this goal; it is now $100
How can information from the 1000 genomes project be used?
What does CRISPR stand for?
Clustered Regularly Interspaced Short Palindromic Repeats
What does CRISPR do?
CRISPR-Cas9 recognizes invading DNA or RNA and cuts it into pieces
• This process can be engineered to introduce new DNA at two cut sites
• Gene drive alters the inheritance of this new DN from 50% to ~100%
What does homologous mean?
What does diploid mean?
pairs of homologous chromosomes
What is a DNA profile?
The number of repeats an individual has in both copies of all 13 STR markers, plus AMEL
What is gene drive?
A manipulation in the copy of genes in which the altered gene is always inherited
What is the significance of parasitism?
• It changes the structure of the brain
• Changes the connections between brain cells
• Changes the activity of the brain, which leads to changes in behaviour