Unit 2 Flashcards
What joins the ends of DNA together in cloning?
T4 DNA ligase
What gel is used to separate small and large bases of DNA?
Agarose - large
Acrylamide - small
What is the order of vector size?
Plasmids, bacteriophage lambda, cosmoids, BACs, YACs
What is a cosmoid?
It’s a bacteriophage that takes out every gene besides DNA replication and packaging so we can fit out own DNA into it. The other essential genes we have the bacteria producing.
What is one major disadvantage of YACs?
Yeast cells undergo a lot of homologous recombination.
What is multi-plex PCR?
Using a sample and a bunch if different primers to amplify more than one gene of interest; need to know how to separate them though (usually by size)
What is the purpose of microarrays?
To view the expression level of a cell and what genes are being expressed.
What is the mutation that causes fragile X?
CGG repeats in the first exon (FMR1) of the FRAXA gene
Can pre-mutation carrier males for fragile X give the full mutation to his children?
No, sperm carrying full mutation is selected against.
What are the gender specific risks for pre-mutation fragile X carriers?
Male - developing ataxia later in life
Female - developing premature ovarian failure
What method is used to detect fragile X pre-mutation genome?
Southern Blot - uses EcoR1 and Eag1 which will only cut unmethylated DNA.
PCR cannot replicate the CGG repeats.
What is Thalassemia?
Alpha or beta globin genes aren’t being produced. Homotetramers are formed by the other leading to inclusion bodies and red blood cell death.
What is the order of produced hemoglobin in development?
Epsilon/zeta, gamma, beta. Alpha produced constantly
What causes sickle cell disease?
A point mutation that switches GAG(G) to GTG(G) or AAG(G).
What restriction site does sickle cell get rid of?
Mnl1
What causes many cases of alpha thalassemia?
Unequal crossover between regions of homology
What is Hb Constant Spring?
UAA to CAA in stop codon that results in 31+ amino acids extra. Unstable alpha globin. Beta globin homotetramers form.
Cystic fibrosis is a defect in what?
A chloride channel
What is the time span of embryogenesis?
From fertilization to 8 weeks
What’s the difference between Carnegie stages and postovulatory age?
Carnegie is described based on physical appearance while postovulatory age is based on time since last ovulation.
What is the morula?
A 16 cell embryo, is compact and forms 3 days after fertilization
What is the zona pellucida?
Extra membrane of an egg cell that persists until the blastocyst gets to the uterine wall
What are trophoblasts?
The edge cells in a blastocyst
What do the inner mast cells differentiate into?
Epiblast - will become the embryo
Hypoblast - will become supportive tissue
What is the process of gastrulation?
Forming an endo, meso and ecto derm from the epiblast
What are contiguous gene syndromes?
They’re syndromes that relate phenotypic abnormalities due to unrelated genes being deleted together
What is spina bifida?
Failure to close the neural tube
What is Williams syndrome?
Deletion if a section of a chromosome that includes the elastin gene as well as other things. Low IQ, excellent music skills, ect.
What is velocardiofacial syndrome?
2nd most common syndrome, cleft palate and conotruncal heart defects characteristics. Small deletion (micro deletion)
What is a homologous gene?
A gene that is similar in structure and evolutionary origin to a gene in another species
What is genome equivalence? How does it relate to differential gene expression?
Every somatic cell has the same genes. However, their expression levels are different depending on the cell
What is the induction system?
Cells release factors that when they reach competent cells, or responders, they react accordingly.
What is pax6?
A competence factor in eye development. Heterozygous loss of pax6 results in aniridia.