Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PCB 3522: Molecular Biology I > Chapter 8: Genome Structure, Chromatin, and the Nucleosome > Flashcards

Chapter 8: Genome Structure, Chromatin, and the Nucleosome Flashcards

1
Q

How long is the human genome?

A

2 meters

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

How do prokaryotes and eukaryotes differ in regards to genomes?

A

Prokaryote genomes are circular and usually have one copy of chromosome. Eukaryote genomes have 2 to 100 chromosomes.

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

How does the genome size correlate to the species complexity?

A

A larger complex organism can call genomes into action in more complicated events then a smaller, less complex organism

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

How does the genome density correlate to the species complexity?

A

More complex organisms have decreased gene density due to intergenic sequences

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

What are genomes?

A

Genomes are wound around nucleosomes and condensed into in chromosomes

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

During mitosis, chromosomes are found with two identical strands called ____________

A

Sister strands

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

How are overlapping genes arranged in eukaryotes?

A

Genomes are typically antiparallel in eukaryotes

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

Define sex chromosomes

A

Carry sex-determining genes.

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

True or False:

Humans are 99% identical to other mammals

A

False

Humans are 92% identical to other mammals

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

Explain the chromosome 2 Fusion

A

The Chromosome 2 fusion is a fusion in humans, but separate in other primates

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

Explain the 44 Chromosome Man

A

Chromosome 14 and 15 are fused.

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

How genetically similar are humans to all neanderthals?

A

99.84% generally identical

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

How genetically similar are humans to all chimps?

A

98.77% generally identical

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

What plays an important in distinguish humans from other animals, and affects expression/regulation?

A

Introns and noncoding intergenic DNA

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

Who (males or females) undergo X inactivation?

A

Females

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

How did the Y chromosome evolve?

A

The Y chromosomes evolved from the X chromosome. Was once identical to X. Evolves fast.

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

Describe repetitive intergenic DNA

A

50% of the human genome DNA is repetitive

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

Describe PAR

A

It is the pseudoautosomal regions (PAR1 and PAR2) of the Y chromosome, homologous to the X chromosome. Genes in this region are inherited in an autosomal rather than a strictly sex-linked fashion

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

Describe SRY

A

It is the male-specific transcription factor for sex determination

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

Chromatin is made up of ______ and ______

A

DNA, Protein

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

What is the smallest virus?

A

Hepatitis delta virus (1700 nt)

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

True or False:

Eukaryotes have polyploid cells

A

True

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

The more complex an organism, the _____ its gene density

A

less

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

The larger an organisms genome size, the ________ its complexity

A

greater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
More complex organisms have decreased gene density due to __________
Intergenic sequences
26
True or False: | The mitochondria genome had genes with overlapping exons
True
27
True or False: | There are 6 million base pairs of DNA per diploid cell
True
28
Define X inactivation
One X undergoes inactivation in the cells of females
29
True or False: | Sex ratio is 50% in all animals
True
30
Define intron
A segment of DNA or RNA molecule which does not code for proteins and interrupts the sequence of genes
31
What causes gene duplication?
- DNA polymerase slippage - Unequal crossing over - Trisomy - Transposon
32
Transposons
Cut themselves out and move to different location
33
Retrotransposons
Transcribed by RNA polymerase into RNA. Then encodes reverse transcriptase and copies themselves somewhere else in the genome
34
________ are derived from ancient viral infections
Endogenous Retroviruses
35
What is the Alu element?
The Alu element is a transposon descended from signal recognition particle which targets proteins to ER
36
Explain the horizontal gene transfer
Genes can be shared horizontally between species
37
What is within the coding RNA?
Messenger RNA with exons
38
Explain alternative splicing
Produces 100,00 transcripts from the 20,000 genes and generate isoforms with different functions. 95% may be an error
39
_________ act as scaffolding, guides, effectors/enhancers the regulate genes, and act as a signal for viral tranSfection.
Long noncoding RNA
40
______ forms a hairpin secondary structure. Regulates post transcriptional gene expression
MicroRNA
41
_____ is a response to foreign RNA and is often 100% complementary
siRNA
42
miRNA can inhibit _________
Translation
43
MicroRNA are _____-specific
Tissue
44
_____ is a type of coding RNA
mRNA
45
Define centromere of chromosomes
Only 1 per chromosome. The point of attachment for kinetochore proteins which link chromosomes to microtubles.
46
Define telomeres of chromosomes
Single-stranded ends of chromosomes, repeats of TTAGGG
47
When do Sister chromatids exists?
S phase to M phase
48
_______ protects the ends of chromosomes. may anchor chromosomes to the edge of the cell during division
Telomeres
49
The _________ is chromosome duplication and chromosome segregation
Cell Cycle
50
Phase at which the cell cycle is at rest (quiescent)
G0
51
Phase of the cell cycle for growth and prearation
G1
52
Explain the S (synthesis) phase
DNA synthesis, each chromosome is duplicated to produce two sets of sister chromatids
53
Phase of the cell cycle that allows preparation for division
G2
54
Explain the M (mitosis) phase
Sister chromatid centromeres are bund by kinetochore proteins, which attach to the mitotic spindles
55
At what phase does DNA replication occurs?
S phase
56
At what phase does DNA segregation occurs?
M phase
57
Cell cycle checkpoints
Cell with DNA damage will arrest in G1 before synthesis
58
Movement in the cell is regulated by ______ and ________
cyclins and cyclin-dependent kinases (CDKs)
59
True or False: DNA replication and histone synthesis which results in two identical sister chromatids per chromosome. At what phase does this occur?
True S phase
60
Sister chromatin are bound by _______
Cohesin
61
When is cohesin added to DNA?
S phase
62
During prophase, ______ is added to condense chromosomes
Codensin
63
What is the function of Aurora B Kinase?
Checks and regulates microtubule attachment, senses tension via phosphorylations
64
Explain the metaphase plate alignment
Kinesin and dynein controls alignment at the metaphase plate.
65
This enzyme cuts cohesin
Separase
66
True or False: | Crossing over is essential to mitosis
False | .... essential to meiosis
67
What is the tension that holds chromosomes together during meiosis 1?
Recombination
68
What is the tension that holds chromosomes together during meiosis 2?
Cohesion
69
What is the tension that holds chromosomes together during mitosis?
Cohesion
70
What are nucleosomes?
The building blocks of chromosomes
71
What is the function of topoisomerase?
Relaxes DNA that is too overwound
72
Describe the solenoid model
A superhelix with six nucleosomes per turn
73
Describe the zigzag model
The longer link passes through the center of the fiber
74
Define acetylation
loosening, activation (HATs and HDACs, which are drug targets)
75
Define methylation
silencing, represseon, occasional activation. Can be mono, di, or trimethylated (HMTs and HDMAs)
76
True or False: | Chromosome organization affects transcription
True
77
True or False: | To access gene, remove the genome by nucleosome sliding, histone exchanging, or nucleosome eviction
True
78
True or False: | Alternating patterns of A-T and G-C benefits the nucleosome
True
79
Histone tail can be modified by _____, _____, and _______
acetylases, methylases, and ATPases
80
The modification of histone tail affects ...
chromatin structure, function, and gene expression
81
Which drug targets loosens and activates the DNA?
HATs and HDACs
82
Serine, arginine, lysine, and threonine can be modified by .....
Phosphorylation, acetylation, methylation, ubiquitination, SUMOylation
83
Which drug targets can silence, repress, and sometimes activates DNA?
HMTs and HDMs
84
Loosening of the DNA is called ______
Acetylation
85
Tightening of the DNA is called _______
Methylation
86
Explain histone code
Proteins can read the modifications and modify gene expression
87
Bromodomains recognizes acetylation or methylation?
Acetylation
88
Chromodomains recognizes acetylation or methylation?
Methylation
89
True or False: | Bromodomains recognizes acetylated lysines
True
90
True or False: | Chromodomains recognizes methylated lysines
True

PCB 3522: Molecular Biology I (8 decks)

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