ch 8

Question 1

overview of the nucleus

Answer 1

largest organelle that holds DNA

site of transcription and DNA replication

Question 2

main components of the nucleus

Answer 2

nuclear envelope
nuclear pores
chromatin
nuclear lamina
nuclear bodies

Question 3

nuclear envelope

Answer 3

pair of phospholipid membranes
inner and outer

Question 4

perinuclear space definition

Answer 4

space between membranes

Question 5

perinuclear space function

Answer 5

controls nucleus shape
helps connect nucleus to other organelles

Question 6

nuclear pore complexes definition

Answer 6

protein pores that surround membranes

Question 7

nuclear pore complexes function

Answer 7

lets certain molecules in or out of nucleus

allows transport of tRNAs, mRNAs, proteins

Question 8

nucleoporins

Answer 8

protein subunits that make up nuclear pore complexes
>1000 subunits make up nuclear pore

Question 9

karyopherins

Answer 9

proteins that help transport molecules across nuclear envelope

Question 10

exportins

Answer 10

karyopherins that export molecules from nucleus

Question 11

importins

Answer 11

karyopherins that import molecules to the nucleus

Question 12

nuclear localization sequence (NLS)

Answer 12

amino acid sequence

Question 13

what protein detaches protein cargo from importin

Answer 13

Ran

Question 14

what is a nuclear export signal

Answer 14

amino acid sequence that tells the cell it needs to exit

Question 15

nuclear lamina

Answer 15

ring of lamin proteins linked together
controls nucleus shape
regulates chromatin and gene expression

Question 16

heterochromatin is localized…

Answer 16

around edge of inside of nucleus
attached to nuclear lamina

condensed chromatin

Question 17

euchromatin is located…

Answer 17

middle of nucleus

loosely condensed chromatin

Question 18

transcription hubs

Answer 18

regions where many genes are being transcribed

Question 19

replication hubs

Answer 19

regions where DNA is being replicated

Question 20

examples of nuclear substructures

Answer 20

nucleolus
cajal bodies
nuclear speckles

Question 21

nucleolus

Answer 21

dense region of nucleus

involved in ribosome production
rRNA is transcribed and processed
ribosomes are assembled

Question 22

what regions are involved in RNA splicing

Answer 22

cajal bodies
nuclear speckles

Question 23

where are components of the spliceosome assembled

Answer 23

cajal bodies

Question 24

where are components of the spliceosome stored

Answer 24

nuclear speckles