Lecture 10-11 Flashcards
What processes take place within nucleus?
Dna replication
Transcription
RNA processing (only translation occurs in cytoplasm)
What does the nucleus consist of?
Nuclear envelope
Nucleoplasm
Nucleolus
What part of the nuclear envelope is connectedwith endoplasmic reticulum membran?
Outer membrane which has ribosomes
How are the lipid bilayer of inner and outer nuclear membranes connected?
At each nuclear pore
Where does the nuclear lamina exist?
Inner membrane of the nuclear envelope
What causes the nuclear envelope to break up into vesicles?
Phosphorylation of lamins which causes the nuclear lamina to dissemble.
How do macromolecules pass between pores of nucleu
By a mechanism that imports proteins to the nucleus and exports RNA to the cytoplasm.
What is the nucleoplasm made of?
Contains chromatin and nuclear matrix.
Chromatin- be seen as dark staining areas which are associated with nuclear membrane, contain condensed chromatic called hetrochromatin.
Euchromatin- light staining areas with more dispersed chromatin, account for the metabolic active chromatin.
What is the klinefleter syndrome?
XXY chromosomes
What is chromatin?
Complex of DNA and protein (lessser impact form
Of chromosomes)
What is a nucleosome?
Two full turns of dna wound around octametric histone core plus the adjacent LINKER DNA
Histone Octomer
Made of 4 pairs of histones
