Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Intro to Molecular Biology & Genetics > Eukaryotic DNA > Flashcards

Eukaryotic DNA Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

what does DNA stand for ?

A

Deoxyribonucleic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does RNA ?

A

Ribonucleic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the role of DNA ?

A

respiratory of genetic information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How long is DNA in human cells ?

A
  • roughly two meters of DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the size of the nucleus ?

A

5μm in diameter (2-10 μm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the DNA paking accomplished by ?

A

specialised proteins that bind to the DNA and fold it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what do the proteins that package DNA generate ?

A
  • a sereis of organised coils and loops = higher lvel if organisation
  • prevent the DNA from becoming an unmagegeable tangle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the most important fuction of DNA ?

A
  • carry genes, because this info specifies all RNA molecules and protein that mame up an organism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does a chromosome consist of ?

A
  • single, long linear DNA molecule
  • they are folded and packed by proteins into a more compact structure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what processes are chromososmes required for ?

A
  • Gene expression
  • DNA replication
  • DNA repair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the name of the protein that keeps chromososmes bound together ?

A

Chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is DNA in Viruses ?

A
  • nacked DNA
  • Protein free packing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is DNA in Prokaryotes ?

A
  • Partially condensed
  • Some proteins bind DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is DNA in Eukaryotes ?

A
  • highly condensed
  • many proteins bind DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are chromosomes/DNA in bacteria?

A
  • circular
  • condensed by supercoiling
  • nucleoid-associated proteins holds their structure
  • DNA ot wrapped arounf protein like in Eukaryotes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the process of DNA condensation in eukaryotes ?

A
  1. Chromatin formation
  2. Fimalment formation
  3. Scaffold formation
  4. Metaphase chromosome formation
17
Q

What happens in chromatin formation ?

A
  1. coils of DNa are wrapped around a core of DNA binding proteins (histones)
  2. resembles beads on a string, each bead is called a nucleosome
  3. 10nm in diametre and 147 bp of DNA
18
Q

what happens in filament formation ?

A
  • the beads on a string chromatin structure of DNA can only be seen in a low salt-buffer
  • Dna is comdemsed further to form a ribbon-like structure called FILAMENT
  • 30nm ribbon
  • reduced lengh of DNA by 100x
19
Q

what does the Linker histone (H1) regulates ribbon formation ?

A
  • linker = the region of DNA between nucleosomes
  • specilalised histone (H1) binds to linker DNA
  • H1 no present within nucleosomes
  • binding H1 regulates formation of the ribbon structure
19
Q

what does the Linker histone (H1) regulates ribbon formation ?

A
  • linker = the region of DNA between nucleosomes
  • specilalised histone (H1) binds to linker DNA
  • H1 no present within nucleosomes
  • binding H1 regulates formation of the ribbon structure
20
Q

what happens in the scaffold formation ?

A
  • 30nm filament is further looped around and anchored to the chromosome scaffold at specific points by specialised proteins
  • loosely condensed structure consisting of 300nm loops is as well as a more condensed struccture of 700nm loops
21
Q

what happens in metaphase chromososme ?

A
  • most compact phase of DNA condensation is only seen during mitosis
  • compact chromosomes lines up at the equator of the cell and become visisble under the microscope
22
Q

what is DNA supercoiling ?

A
  • Twisting of DNA likea rope
23
Q

What does supercoilling do ?

A
  • reduce the space required for DNA packaging (efficient DNA storage)
24
Q

what are the 2 types of supercoilling ?

A

positive and negative supercoilling

25
Q

what is positive supercoiling ?

A
  • when DNA is overwound
  • they are formed when they are unwunded by helicase
  • enzyme (DNA gyrase) to reduce the strains
26
Q

what is negative supercoiling ?

A
  • underwounded DNA
  • most DNAs are negatively supercoiled by enzymes called TOPOISOMERASES

Intro to Molecular Biology & Genetics (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions