Flashcards in Bittel and Ferguson Deck (59)
Is DNA parallel or antiparallel
How often is there a turn in DNA
one turn every 10 bp
What digest linker DNA?
What is a nucleosome core particle made up of?
8 histone proteins
-2 molecules each of H2A, H2B, H3, H4
-2x standee DNa that is 147 nucleotide pairs long
What are the universal features of cells on earth?
-all cells store their heredity info in the same linear chemical code: DNA
- all cells replicate their hereditary information by templated polymerization
- all cells translate RNA into protein in the same way
- each protein is encoded by a specific gene
- all cells function as biochemical factories dealing with the same basic molecular building blocks
- all cells are enclosed in a plasma membrane across which nutrients and waste materials pass
-life requires free energy
What does acetylation do for genes? methylation?
What is an Okazaki fragment?
chunk of DNA on lagging strand
look at DNA repair pathways
What is homologous recombination
crossing over and gene conversion occurring in same chromosome, multiple opportunities for genetic reassortment
What is a DNA only transposon?
short invited repeats at each end
What enzyme is required for movement in DNA only transposon?
what is the mode of movement for DNA only transposon?
moves as DNA, either by cut and paste or replicative pathways
describe retroviral like retrotransposons
directly related long terminal repeats at each end
retroviral like retrotransposons enzyme
reverse transcriptase and integrase
retroviral like retrotransposons move of movement
moves via an RNA intermediate whose production is driven by a promoter in the LTR
describe nonretroviral retrotransposons
poly A at 3' end of RNA transcript, 5' end often truncates
nonretroviral retrotransposons enzyme
reverse transcriptase and endonuclease
nonretroviral retrotransposons move of movement
moves via an RNA intermediate that is often synthesized form a neighboring promotor
____ in somatic cells direct differentiation into Sertoli cells instead of follicle cells
What do Sertoli cells do?
secrete anti-mullerian hormone to suppress female development, causing mullerian duct to regress
What do leydig cells do?
In the absence of sry, what occurs?
genital ridge becomes ovary
PGC becomes egg
somatic cells differentiate into follicle cells (support cells) and theca cells (estrogen producing cells)
are gametes haploid or diploid?
What do capacitated sperm use to penetrate granulose cells?
What does the zona pellucida act as?
The zona pellucida induces sperm to undergo ______ reaction, which does what?
acrosome, contents help sperm to tunnel through the zona pellucid and alters sperm so it can bind and fuse with plasma membrane of egg
what do membrane proteins ZP1, 2 and 3 do in binding of the sperm to the egg
ZP 2 and 3 form long filaments
ZP1 cross link the filaments
What is the central dogma of biology
DNA is transcribed to messenger RNAs which act as templates for protein synthesis in translation
What are the three phases of translation?