Brainscape's Knowledge GenomeTM

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


See full index

BIO 1090 > Lecture #9 > Flashcards

Lecture #9 Flashcards

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

What are the three parts to a DNA nucleotide?

A

Phosphate group, five-carbon sugar, and nitrogenous bases

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

What are the 4 nitrogenous bases?

A

Adenine, Guanine, Cytosine, and Thymine

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

Nucleotides are connected by …?

A

phosphodiester bonds

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

Is DNA polar or non-polar?

A

polar

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

What identifies the 5’ end of a DNA strand?

A

free phosphate group

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

What identifies the 3’ end of a DNA strand?

A

free hydroxyl group

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

how are the DNA strands held together?

A

with hydrogen bonds between the bases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the most common form of DNA?

A

B-DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is one characteristic of B-DNA?

A

Contains a major and minor groove

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are eukaryotic chromosomes composed of?

A

DNA, RNA, Histones, Non-Histone proteins, and non-chromatin nuclear constituents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many levels of condensation are there in eukaryotic chromosomes?

A

3

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

What occurs during the first level of chromosomes in eukaryotic chromosomes?

A

Packaging DNA into nucleosomes – produces a 10nm fibre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is DNA packed into nucleosomes?

A

DNA links between core histones of nucleosomes, 146 bp of DNA wrapped 1 ¾ turns around the histone octamer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the final steps in the first level of condensation?

A

DNA is wrapped around a nucleosome core of 8 histone proteins and anchored by a 9th
There are two molecules of each histones: H2A, H2B, H3, H4 in the nucleosomal core plus one molecule of Histone H1 to further stabilizer the structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens during the second level of condensation in eukaryotic chromosomes?

A

an additional folding or supercoiling of the 11 nm fibre to produce a 30 nm fibre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the second level of condensation in eukaryotic chromosomes involve?

A

nucleosomal interactions, Histone H1 and the solenoid and zig-zag DNA structure

17
Q

What happens during the third level of condensation in eukaryotic chromosomes?

A

Attachment of the 30nm fibre at many positions to a (non-histone) protein scaffold

18
Q

What are telomeres?

A

consists of 500-3000 copies of the DNA sequence repeated on the ends of chromosomes

19
Q

What are three important factors of telomeres?

A

Resist degradation by DNases, Prevent fusion of chromosomal ends, and facilitate replication of the ends of the linear DNA

20
Q

What are centromeres?

A

Provides the point of attachment of sister chromatids and of chromosomes to microtubules in the mitotic spindle

21
Q

What is the structure of the metaphase chromosome?

A

consists of a 30nm fibre

22
Q

What is a metaphase chromosome?

A

DNA in its most condensed form

BIO 1090 (12 decks)

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