Genetic Engineering

The correct restriction enzyme makes a cut at the correct site. This helps join the gene and vector properly.

Many substances are produced in a host cell, so the desired product must be separated. Purification is especially important in medicine production.

Restriction enzyme cuts, ligase joins, vector carries, and selection shows correct cells. This order gives easy exam revision.

A gene is a DNA segment that carries information for a trait. For exams consider it the functional unit of heredity.

Plasmids are small DNA molecules that can carry foreign genes. For exams remember plasmid as a common vector.

Restriction enzymes cut DNA at specific recognition sites. For exams remember them as molecular scissors.

A vector helps deliver a foreign gene into a host. Plasmids and viruses are examples of vectors in exams.

A host cell can replicate and express recombinant DNA. For exams think of it as the workshop for the gene.

In transformation a cell takes up external DNA. For exams connect it with gene entry into a cell.

A selectable marker helps select transformed cells. Antibiotic resistance gene is a common exam example.

PCR makes many copies of a selected DNA segment. For exams remember it as a DNA amplification technique.

Gel electrophoresis separates DNA fragments by size. For exams remember smaller fragments move faster.

A DNA probe identifies target DNA by binding to a complementary sequence. For exams remember the rule of complementarity.

In bacteria plasmid is usually small circular DNA in cytoplasm. For exams remember it as separate from the chromosome.

A cloning site is the place in a vector where a foreign gene is inserted. For exams remember it as an insertion site.

A foreign gene is a gene introduced into the host from outside. In exams it may also be called the desired gene.

Human insulin has been produced using recombinant DNA technology. For exams remember it as a key example of medical biotechnology.

An organism whose genes are artificially modified is called a GMO. For exams remember its full form as genetically modified organism.

Bt cotton has been given insect resistance. For exams remember it as an example of agricultural biotechnology.

Agrobacterium is a natural tool for transferring genes into plants. For exams connect it with plant gene transfer.

The CRISPR-Cas system recognizes a specific DNA sequence and enables targeted changes in it; therefore, it is commonly used for gene editing. Measuring soil moisture is the function of an agricultural sensor, not CRISPR. Exam tip: associate CRISPR with targeted DNA modification and gene editing.

The same restriction enzyme creates compatible ends that are easier to join. For exams connect this with sticky ends.

Sticky ends help DNA fragments join through complementary bases. For exams remember them as useful for recombination.

Blunt ends form when both strands are cut at the same position. For exams distinguish them from sticky ends.

In ligation the gene is joined to the vector using DNA ligase. For exams remember it as the DNA joining step.