Intro to Euk Genetics Flashcards
What did the icelandic pedigree for cancer lead to us finding?
found clusters of males in the fmaily tree getting breaqst cancer
lead to finding of BRCA2 gene - b cancer causing
how did plant breeding techniques lead to india’s what output matching its population growth?
conventional wheat was susceptible to damage and stuff
crossed semi dwarf with conventional to make hybrids
got increased of plants less susceptible to damage
how did researchers discover the genetic basis of the circadian rythm
using drosophila melanogaster (already knew it has a circadian rythm, wake in day sleep at night i wanna sleep rn)
mutated the drosophola to see which mutation affected the rythm
found the period mutant
could mutate to chang ethe sleep cycle
identified the gene and the protein i encoded for
worked out pathway in which circadian rythm works
how did they test the period gene for circadian rythms in mice
isolated the suprachiasmatic nucleus
put it in the dark so light doesnt affect it
marked the period protein
saw that the protein lights up at night and dies down in the day, w/o external stimuli
how many protein coding genes estimated in humans
21,000
but thousands of other that dont code for proteins, most control gene expression
gene definition, both as its effect and as a DNA molecule
efftect on phenotype:
inherited factor that affects the characteristics of an individual
but as DNA molecule:
part of chromosome that’s involved in transcription of DNA to RNA, including exons introns etc etc
where genes located
on chromosomes, one paternal one maternal (diploid
what is a centromere
assembles kinetochore (complexof proteins)
these attach to microtubules
what is a telomere
each end of chromosome, needed to stabilise
have T-loop
stops them from recombining with other DNA or fusing w/ other chromosomes
what happens to telomeres over time
shorten after each round of DNA replication and cell division until SENESCENCE - no longer able to replicate
how is telomere shortening prevented
certain cell types (e.g. stem cells and germ cells)
have the enzyme telomerase
prevents shortening during DNA rep
immortalllll
acc occurs in cancer cells where telomerase is reactivated, so it can replicate w/o telomere being damaged
sexual life cycle in humans
diploid zygote
mitosis and development leads to adult
adult has haploid sex cells
fertilization
diploid zygote boom
whats something different in the sexual life cycles in plants &some algae
some organisms are haploid (e.g. gametophyte)
purpose, process and location of mitosis
purpose - produce 2 geneticlaly identical diploid daughter cells
process - a single cell division
location - all tissues
purpose, process and location of meiosis
purpose - produce 4 haploid gametes from diploid mother cell
process - 2 sequential cell divisions
location - gonads
