Technologies such as Oxford Nanopore mitigate some repeat issues but still struggle with really long repeats because:

Read error rates are too high for distinguishing repeat unit variants

In shotgun sequencing, what does the term “coverage” typically represent?

Average number of times each base in the genome is read

GenBank is a key database in genomics. Which statement best describes its primary function?

Public repository of nucleotide seq (DNA and RNA) from all organisms

Illumina is a next-gen sequencing technique that uses ~150 bp reads. What is the challenge in sequencing long repeats?

Ambiguous mapping of identical reads

In metagenomics, why does the presence of multiple microbial species complicate genome assembly and analysis?

Mixed samples generate a chaotic reads from potentially hundreds of species

During metagenomic studies, scientists often rely on reference databases like GenBank to identify species. A limitation?

Many microbial species remain unsequenced, leaving large knowledge gaps.

In next-generation sequencing-by-synthesis (e.g., Illumina), what is the key feature of the method?

Light is generated by adding a labeled nucleotide to the growing DNA

Which advantage of long-read sequencing is most critical for resolving long tandem repeats?

Ability to span entire repeat arrays without breaks

studbud

3/25 BIORA Genome Evolution

10 termsStudBud Administration6 plays

Imported from external platform

Flashcards10 cardsFPractice quizPHost liveL

Questions 10

Answers

1
Technologies such as Oxford Nanopore mitigate some repeat issues but still struggle with really long repeats because:
Its read length is still not long enough (< 10 kb)
Repeats create secondary structure that inhibit ligation
Coverage will be too low
Read error rates are too high for distinguishing repeat unit variants
2
In Illumina sequencing-by sequencing-by-synthesis, the Q30 threshold indicates what level of base-call accuracy?
99.9%
95%
99.999%
99%
3
In shotgun sequencing, what does the term “coverage” typically represent?
Average number of times each base in the genome is read
Percentage of reads that map to repeated sequences
Probability that the library preparation succeeded
Number of polymerases used per reaction
4
GenBank is a key database in genomics. Which statement best describes its primary function?
Proprietary database hosting only human genome data
A specialized database for protein structural data only
A closed-access database for patent-protected gene sequences
Public repository of nucleotide seq (DNA and RNA) from all organisms
5
Illumina is a next-gen sequencing technique that uses ~150 bp reads. What is the challenge in sequencing long repeats?
Polymerase slips during synthesis
Base-calling errors
Ambiguous mapping of identical reads
High GC-content causing drop-out
6
In metagenomics, why does the presence of multiple microbial species complicate genome assembly and analysis?
All microbes share a single universal genome, making them indistinguishable
Mixed samples generate a chaotic reads from potentially hundreds of species
Short-read sequencing technology cannot process microbial DNA at all
Most microbial genomes have similar G+C content, causing mapping confusion
7
During metagenomic studies, scientists often rely on reference databases like GenBank to identify species. A limitation?
Reference databases only accept data from eukaryotes.
Many microbial species remain unsequenced, leaving large knowledge gaps.
The format used by GenBank is obsolete.
Databases are private and unavailable to researchers.
8
In next-generation sequencing-by-synthesis (e.g., Illumina), what is the key feature of the method?
Sequencing is achieved by breaking DNA into single bases
DNA is sequenced via direct measurement of electrical current changes
Light is generated by adding a labeled nucleotide to the growing DNA
Each newly added nucleotide is removed before the next base is incorporated
9
Canonical telomere repeat sequence in human:
TTAGGG
AATTG
GACTCC
ATTAG
10
Which advantage of long-read sequencing is most critical for resolving long tandem repeats?
Direct chemical measurement of base composition
Reduced PCR amplification bias
Ability to span entire repeat arrays without breaks
Faster computational alignments over short reads

3/25 BIORA Genome Evolution Flashcards | StudBud