Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Genetics > Lecture--Chapter 12 > Flashcards

Lecture--Chapter 12 Flashcards

(84 cards)

Start Studying
1
Q

Chromosomes have a DNA helix of 2 strands, which are complexed with _____.

A

proteins

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

The relaxed DNA molecule of a single chromosome is longer than the ________ of the cell.

A

greatest dimension

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

Human genome (23 chromosomes) is about _____ long.

A

1 meter

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

To fit into cells, DNA must be ____.

A

compacted

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

generally a single circular DNA helix

A

bacterial chromosome

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

main chromosome + any plasmids:

A

genome

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

Multiple copies of genome may be present during times of _____.

A

fast growth

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

Genome is located as a _____, not in a nucleus.

A

nucleoid

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

bacterial “chromosome” (lacks chromatin)

A

genophore

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

Bacterial chromosome is a few million ____ in length.

A

nucleotides

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

E. coli has ~______ base pairs.

A

4.6 million

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

Haemophilus influenzae has ~_____ base pairs.

A

1.8 million

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

structural genes (encoding proteins)

A

transcribed gene sequences

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

intergenic regulatory regions

A

nontranscribed DNA segments

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

start site for DNA replication

A

origin of replication

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

Bacterial DNA must be packed about ______ smaller than its relaxed length.

A

1000-fold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Intergenic and repetitive sequences include regions with roles in ______.

A

chromosome packing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

With bacterial DNA. compaction is largely accomplished by ____ and ____.

A

looping; supercoiling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

additional coils due to twisting forces

A

supercoil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

different structural conformations of a molecule

A

topoisomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Coiled coils form loops in response to _____.

A

twisting forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

_____ supercoiling is the ______ state.

A

negative; normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Negative supercoiling creates tension which promotes _____.

A

strand separation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Negative supercoiling: DNA replication in _____.

A

cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Negative supercoiling: DNA transcription for ______.
gene expression
26
Supercoiling is _____.
regulated
27
enzymes that either create or reduce supercoiling
topoisomerases
28
reduce ("relax") negative supercoiling
type I topoisomerases
29
break a single strand, allow rotation around the unbroken strand, and re-form phosphodiester backbone
type I topoisomerases
30
creates negative supercoiling
DNA gyrase
31
DNA gyrase plays a part in ____.
type II topoisomerases
32
makes a double strand break, redirects the broken strand, then re-seals
type II topoisomerases
33
essential for bacteria to survive
DNA gyrase
34
_______ is one way to cure some bacterial diseases.
inhibiting DNA gyrase
35
broad-spectrum antibiotics for UTIs, hospital-acquired pneumonia
quinolones
36
drug-resistance, side effects issues
quinolones
37
A eukaryotic genome is the complete set of _____ chromosomes.
nuclear
38
Long ____ DNA molecules complexed with proteins.
linear
39
Nearly all eukaryotic genomes have ______ of DNA.
multiple pieces
40
human genome:
3.1 billion nucleotides, 22,000 genes
41
human genome: initial draft completed in ____, final draft in ____.
2003; 2006
42
human genome: useful for ____ research, _____, _____ studies.
biomedical; forensics; evolution
43
Large variation in genome size among _____.
species
44
many per chromosome, about every 100,000 base pairs
origins of replication
45
one per chromosome
centromere
46
defined DNA sequence of ~125 base pairs, yeast
point centromere
47
long repetitive DNA sequences, most common
regional centromere
48
both ends, specialised repeated sequences
telomeres
49
stabilise and protect the ends of the chromosomes
telomeres
50
the number of times a particular motif appears throughout a genome
DNA sequence complexity
51
usually occur only once or a few times
unique sequences
52
encode proteins (gene exons)
structural genes
53
control expression
regulatory regions
54
100s to 1000s of copies
moderately repetitive sequences
55
Moderately repetitive sequences: _____ and ____ protein genes.
ribosomal RNA; histone
56
Moderately repetitive sequences: remnants of _____.
transposable elements
57
10s of thousands to millions of copies
highly repetitive sequences
58
Highly repetitive sequences: Alu and LINE ______.
transposable elements
59
clusters of highly repetitive sequences (satellites)
tandem arrays
60
Tandem arrays: polymerase errors in ____.
replication
61
Tandem arrays: _____ (chromosome pairing) and ____.
centromeres; telomeres
62
Eukaryotic DNA must be _____ packed to fit.
tightly
63
Eukaryotic DNA increased ___ and ____ makes compaction difficult.
size; complex structure
64
a double-stranded segment of DNA wrapped around an octamer of histone proteins
nucleosomes
65
basic proteins that bind to negatively charged phosphates in the minor groove of the DNA backbone
histones
66
Eukaryotic Chromosome Compaction: DNA is wrapped around the nucleosome (_____).
beads on a string
67
Eukaryotic chromosome compaction: nucleosomes coil to form ______.
30 nm fiber
68
Eukaryotic Chromosome Compaction: 30 nm fiber organised into ______.
radial loop domains
69
Eukaryotic Chromosome Compaction: MARs are:
matrix attachment regions
70
Eukaryotic Chromosome Compaction: Additional packing of radial loops and further packing is seen in ____ chromosomes.
metaphase
71
discrete nuclear locations of each chromosome
chromosome territories
72
Compaction state of ____ chromosomes is variable.
interphase
73
tightly compacted regions, generally not transcribed
heterochromatin
74
always heterochromatic and inactive
constitutive heterochromatin
75
chromatin that can interconvert between heterochromatin and euchromatin
facultative heterochromatin
76
less condensed regions capable of gene transcription
euchromatin
77
the entire chromosome is packed into heterochromatin
mitotic chromatin
78
compacted radial loops remain anchored to a _____.
protein scaffold
79
protein that coats individual chromosomes at the beginning of mitosis, then folds the strands.
condensin
80
loops on matrix fiber
euchromatin
81
matrix fiber folded
heterochromatin
82
chromatin attached to scaffold proteins
condensin
83
family of ATPases that catalyse changes in chromosome structure (condensins and cohesins)
structural maintenance of chromosomes (SMC) proteins
84
proteins that promote binding between sister chromatids and regulate their separation during nuclear division
cohesin

Genetics (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions