Molecular Genetics and Biotechnology Quiz

Naturally occurring enzymes that precisely cut long DNA sequences (15-40 base pairs). They are highly specific but have limited flexibility in targeting.

Artificial restriction enzymes composed of a zinc finger DNA-binding domain and a DNA cleavage domain. They can be engineered to target specific DNA sequences for editing.

Similar to ZFNs, but use a more easily extendable DNA-binding motif called TALEs. This allows for greater targeting flexibility.

A revolutionary gene editing system using a single guide RNA (sgRNA) and a Cas9 nuclease. The sgRNA guides Cas9 to a specific target DNA sequence, where it makes a double-stranded break.

A specific DNA sequence that must be present adjacent to the target sequence for Cas9 to function. It helps Cas9 distinguish between target and non-target DNA.

The unintended cleavage of DNA sequences that are similar but not identical to the intended target sequence. This can lead to unintended mutations and unwanted consequences.

An alternative gene editing system that uses short interfering RNAs (siRNAs) or microRNAs as guides in eukaryotes, and DNA fragments as guides in archaea.

A short, double-stranded RNA molecule that guides Argonaute to specific targets for silencing or degradation.

Enzymes used by bacteria to defend against viruses that cut DNA at specific nucleotide sequences called restriction sites

Restriction enzymes used in molecular genetics. They recognize short palindromic sequences and make double-stranded cuts, producing either sticky or blunt ends

A technique that uses restriction enzymes and gel electrophoresis to analyze variations in homologous DNA sequences

A technique that separates molecules based on size and electrical charge using an electric current. Smaller molecules move faster towards the positive electrode

A technique that transfers DNA fragments from a gel to a solid medium, allowing for further analysis of specific DNA sequences

A laboratory technique used to amplify specific DNA fragments in vitro, doubling the target sequence with each cycle

A more precise method for quantifying DNA using fluorescence to track amplification during each cycle and create an amplification curve

The cycle number in qPCR where the amplification of DNA exceeds a set threshold. A lower Ct value indicates a higher starting amount of DNA

Duplications or deletions of particular segments of DNA. These variations can be analyzed using qPCR

Amplification of a specific DNA fragment using bacteria. Plasmids (circular DNA molecules) are used as vectors to carry the foreign DNA

Specialized cloning vectors designed to make it easier for the inserted foreign DNA to be transcribed and translated inside the target organism

A method of DNA sequencing that uses dideoxynucleotides (ddNTPs) to terminate the DNA synthesis process at specific locations

A technology that can sequence millions of DNA fragments simultaneously, providing rapid and cost-effective sequencing of genomes

Can sequence longer fragments than NGS, using different approaches such as PacBio sequencing or Nanopore sequencing

A third-generation sequencing technique that uses a nanopore (tiny hole in a membrane) to detect electrical current changes as a single DNA molecule passes through

The two main pathways are Non-homologous end joining (NHEJ) and Homology-directed repair (HDR). NHEJ is more frequent but less precise, often introducing small insertions or deletions, while HDR uses a template to repair the break, offering more accurate repair.

Both CRISPR-Cas9 and Argonaute are engineered tools for gene editing using guide RNAs. CRISPR-Cas9 relies on a Cas9 enzyme to cleave DNA, while Argonaute uses small DNA or RNA guides to target and modulate gene expression without DNA cleavage.

All molecular scissors, including meganucleases, ZFNs, TALENs, and CRISPR-Cas9 systems, induce double-strand breaks (DSBs) in DNA, relying on the cell's natural DNA repair mechanisms to make changes in the genome.

CRISPR systems use guide RNAs that hybridize with specific DNA sequences, while Argonaute relies on small DNA or RNA guides that recognize RNA targets in the cell.

It starts with an observable phenotype (trait) and then identifies the underlying gene causing it. It involves random mutagenesis and phenotypic screening.

It begins with a gene and investigates its function by altering its expression. It involves targeted gene manipulation and analysis of the resulting phenotype change.

Gene knockout permanently inactivates or removes a gene, while gene knockdown only temporarily reduces its expression. These often involve RNA interference.

Ectopic gene expression occurs when a gene is expressed in a different location or time than it normally is. This can be achieved by manipulating the promoter or using other techniques.

Transgenic organisms are genetically modified to include a transgene, an engineered piece of DNA. This transgene can be inherited by future generations if integrated into the germline.

Map-based sequencing involves constructing genetic and physical maps of a genome to determine the order and distance between genes and markers, followed by sequencing overlapping DNA fragments.

Shotgun sequencing involves randomly fragmenting the DNA, cloning and sequencing these fragments, and then assembling them based on overlapping regions.

A haplotype is a specific combination of alleles at different loci inherited together from one parent on a single chromosome.

Linkage disequilibrium occurs when alleles at different gene loci are not randomly associated and occur together more or less frequently than expected by chance, due to their proximity on a chromosome.

GWAS attempt to identify genetic regions associated with specific traits. They use tag-SNPs to represent haplotypes and find common variants linked to the trait, potentially indicating the causal variant.

Genes that are evolutionarily related, meaning they share a common ancestor. They can be either orthologs or paralogs.

Homologous genes found in different species that evolved from the same gene in a common ancestor. They usually retain the same function.

Homologous genes found within the same species that arose from gene duplication events. They usually retain the same function but may have different specificities.

The study of all RNA molecules present in an organism or tissue, including both coding (mRNA) and non-coding RNA (tRNA, rRNA, etc).

The study of the proteome, which is the complete set of proteins produced by an organism or tissue.

Heritable changes in gene expression that occur without alterations to the DNA sequence itself. Modifications affect how genes are read and used.

Addition of a methyl group to a cytosine base in DNA. Typically occurs in CpG islands.

Changes to the histone proteins, the structures around which DNA wraps. These changes, like acetylation, methylation, and phosphorylation, affect how tightly DNA is wrapped.

RNAs that do not code for proteins but can regulate gene expression by interacting with mRNA or recruiting chromatin-modifying complexes.

Enzymes that establish the epigenetic code by adding modifications to DNA or histones. Examples include histone acetyltransferases (HATs) and histone methyltransferases (HMTs).

Proteins that interpret the epigenetic code, binding to specific modifications and then recruiting other proteins or complexes to influence gene expression.

Enzymes that remove modifications from DNA or histones, resetting the epigenetic code.

A system of modifications on histone tails that influences gene expression. For example, acetylation is associated with active genes, while methylation is often associated with gene repression.

This law predicts that allele and genotype frequencies in a population will remain constant from generation to generation if certain conditions are met.

Factors that can alter allele and genotype frequencies in a population, driving evolutionary change. These include mutation, migration, genetic drift, and natural selection.