Ch-3-Nucleus and Dna Flashcards
What helps molecules move btw nucleus and cytosol?
nuclear pores
What is dumbbell shapped signifying
its the shape of nucleus with cell type, normally spheroid but dumbbel is leukemia anemia
What is the nuclear envelope compartments (4)
-Outer n.memb = cont to the RER
-Peri n.space = cont ER lumen
-Inner n.memb= binding site for n.lamina
(NPC allow passing of molecules)
NPC
150nm thick
What is the nucleoporins surrounding (3)
Transmembrane ring - anchors NPC
Scaffold - layer of the ring
Channel - centroal pore
Which DNA is un-expressed
Heterochromatin
From the chromatin type which has less coil
Euchromatin
What is the N.Lamina connected to?
To chromatin , allows DNA replication and transcription
How is N.Import done
Proteins are bound to Import-R , those proteins have a Nucl Local signal that are bound to (phe-gly- repeats) fibrils.
What disciple involves the study of the genetic make up
Genomics
What is responsible for low correlation of complexity to chr. #
Non-coding DNAaka 1.1% actual is coding aka exons.
what is it called when parts of the DNA’s genome can move around
Trasnposons
How much % needed of a genetic variation for a it to gain/loose a fxn
1% is just mutation, >1 is called a polymorphism,
What type of genetic variation explains a pattern of mendelian genetics
Mutation do
What does chargaff rule signify
A=T
G=C
Purines and Pyrimidines with H # bonds
T-C = pyrm
A-G= pur
AT - 2H
GC- 3H bonds
What type of bonds link DNA
Phosphodiester bond
What direction is strand direction in
5’ P–>3’OH
This type of mutation is when theres a substitution of of an A.A to another
Misense
This type of mutation is when theres a pre-mature stop
NonSense
This type of mutation is an insertion or deletion
Frameshift
What are 2 ways for DNA to be packaged
DNA Supercoiled
or
Nucleosomes
What shape does supercoiling give
solenoidal
What gives a R. handed confirmation twist
Overwinding gives +’ve
What gives the DNA space to seperate
Underwinding with a -‘ve supercoil
What mediates the overwinding or underwinding
Type 1 topoisiomersae will break 1 strand
where as Type 2 will break both strand
What makes gene regulation possible
chromatin remodleing
What is it referred to when centromere is located at one end of the chromosome
telo-centric
What is it referred to when centromere is located at the centre
Metacentric
What is it referred to when centromere is located at one end of the chromosome
Acrocentric
