Bio 251 Spring 2025 Final Exam Study Guide Vocabulary

Flashcards of terms related to recombinant DNA, molecular analysis, biotechnology, epigenetics, developmental genetics, and cancer genetics mentioned in the study guide to help with exam preparation.

Restriction enzymes

DNA molecules that cut DNA at specific sequences.

Restriction sites

Specific DNA sequences recognized by restriction enzymes.

Cohesive ends

Staggered cuts in DNA that leave short, single-stranded tails.

Blunt ends

Cuts in DNA that result in non-staggered ends.

Engineered nucleases

Nucleases that are designed to target specific DNA sequences.

Zinc-finger nucleases

Engineered proteins that can be designed to bind to specific DNA sequences and cleave the DNA.

Transcription activator-like effector nucleases (TALENs)

Engineered proteins that can be designed to bind to specific DNA sequences and cleave the DNA.

CRISPR-Cas system

A gene-editing system that uses a guide RNA to target a specific DNA sequence for cleavage by the Cas9 enzyme.

Homologous recombination

Repair of DNA double-strand breaks using a homologous template.

Nonhomologous end joining

Repair of DNA double-strand breaks without a homologous template, often leading to insertions or deletions.

Gel electrophoresis

A method for separating DNA fragments based on size using an electric field.

Probe

A labeled DNA or RNA sequence used to identify complementary sequences by hybridization.

Polymerase chain reaction (PCR)

A technique for amplifying specific DNA sequences using repeated cycles of DNA synthesis.

Gene cloning

The process of inserting a DNA fragment into a vector and replicating it in a host cell.

Cloning vector

A DNA molecule that can carry foreign DNA into a host cell and replicate there.

Linkers

Short, synthetic DNA sequences added to the ends of DNA fragments to facilitate cloning.

Expression vectors

Vectors designed to produce a protein product from a cloned gene.

Transformation

The process of introducing foreign DNA into a cell.

In situ hybridization

A technique for detecting specific DNA or RNA sequences in cells or tissues.

Dideoxy sequencing

A method for sequencing DNA by incorporating dideoxynucleotides that terminate DNA synthesis.

Illumina sequencing

A high-throughput method for sequencing DNA based on reversible terminator chemistry.

DNA fingerprinting

A method for identifying individuals based on their unique DNA profiles.

Forward genetics

A method for identifying genes by starting with a mutant phenotype and identifying the responsible gene.

Reverse genetics

A method for determining gene function by starting with a gene and creating a mutation to observe the resulting phenotype.

Targeted mutagenesis

The process of introducing specific mutations into a gene of interest.

Site-directed mutagenesis

Introducing a mutation at a specific site in a gene.

Oligonucleotide-directed mutagenesis

Using synthetic oligonucleotides to introduce specific mutations into a gene.

Transgene

A gene that has been introduced into a new organism.

Gene therapy

The introduction of genes into human cells to treat disease.

Epigenetics

The study of heritable changes in gene expression that do not involve alterations to the DNA sequence itself.

Epigenesis

The theory that development is a gradual process of increasing complexity.

Epigenome

The complete set of epigenetic modifications in a cell or organism.

Methylation

The addition of a methyl group to DNA, often associated with gene silencing.

Acetylation

The addition of an acetyl group to histone proteins, often associated with increased gene expression.

Epigenetic marks

Chemical modifications to DNA or histone proteins that influence gene expression.

X inactivation center

A region on the X chromosome that controls X inactivation.

Xist lncRNA

A long non-coding RNA that is involved in X inactivation.

Tsix

An RNA molecule that is transcribed from the opposite strand of the Xist gene and acts as an antagonist to Xist.

Jpx

A gene that promotes Xist expression on the X chromosome to be inactivated.

PRC2

A protein complex involved in transcriptional repression and chromatin remodeling.

Pluripotency

The ability of a cell to differentiate into any cell type.

Induced pluripotent stem cells

Stem cells that are generated from differentiated cells by reprogramming.

Paramutation

An interaction between two alleles that results in heritable change in gene expression of one allele.

Epialleles

Alleles that produce different phenotypes due to epigenetic modifications.

Genomic imprinting

Genes that are expressed in a parent-of-origin-specific manner.

Genetic conflict hypothesis

The idea that genomic imprinting evolved because of conflicting interests between males and females over resource allocation to offspring.

Totipotent cell

A cell that has the potential to differentiate into any cell type, including extraembryonic tissues.

Determination

The process by which a cell becomes committed to a particular fate.

Egg-polarity genes

Genes that establish the anterior-posterior axis in the early embryo.

Segmentation genes

Genes that control the formation of segments in the developing embryo.

Homeotic genes

Genes that specify the identity of different body segments.

Morphogen

A protein that diffuses from a source and specifies different cell fates at different concentrations.

Gap genes

A type of segmentation gene that defines broad regions of the embryo.

Pair-rule genes

A type of segmentation gene that defines alternating segments of the embryo.

Segmentation-polarity genes

Genes that define the anterior and posterior compartments within each segment.

Homeobox genes

A DNA sequence found in homeotic genes that encodes a DNA-binding domain.

Hox genes

A family of related genes that control body plan development in animals.

Sepals

The outermost structures of a flower, typically green and protective.

Petals

The colorful, often fragrant structures of a flower that attract pollinators.

Carpels

The female reproductive structure of a flower, consisting of the stigma, style, and ovary.

Stamen

The male reproductive structure of a flower, consisting of the anther and filament.

Class A genes

Homeotic genes that control the development of sepals and petals.

Class B genes

Homeotic genes that control the development of petals and stamens.

Class C genes

Homeotic genes that control the development of stamens and carpels.

Apoptosis

Programmed cell death, characterized by controlled self-destruction of the cell.

Necrosis

Uncontrolled cell death, often caused by injury or infection.

eyeless gene

A gene that controls eye development in Drosophila.

Antigen

A molecule that elicits an immune response.

Antibodies

Proteins produced by B cells that bind to specific antigens.

Humoral immunity

Immunity mediated by antibodies produced by B cells.

Cellular immunity

Immunity mediated by T cells.

Clonal selection

The process by which lymphocytes that recognize self-antigens are eliminated.

Primary immune response

The initial immune response to an antigen.

Secondary immune response

A rapid and stronger immune response to an antigen that has been encountered before.

Memory cells

Long-lived lymphocytes that can respond quickly to a previously encountered antigen.

T cells

Lymphocytes that mediate cellular immunity.

B cells

Lymphocytes that produce antibodies.

Autoimmune disease

A disease in which the immune system attacks the body's own tissues.

Multiple sclerosis

An autoimmune disease in which the immune system attacks the myelin sheath of nerve cells.

Lupus

An autoimmune disease in which the immune system attacks various tissues and organs.

Insulin-dependent diabetes mellitus

An autoimmune disease in which the immune system attacks the insulin-producing cells in the pancreas.

T cell receptors

Proteins on the surface of T cells that bind to antigens presented by other cells.

Immunoglobulin

A protein that recognizes and binds to antigens.

Somatic recombination

The process by which antibody genes are rearranged to create a diverse repertoire of antibodies.

Immune rejection

The rejection of a transplanted organ by the recipient's immune system.

MHC antigens

Proteins on the surface of cells that present antigens to T cells.

Histocompatibility

The degree to which the MHC antigens of a donor and recipient match.

Benign tumor

A non-cancerous tumor that does not spread to other parts of the body.

Malignant tumor

A cancerous tumor that can spread to other parts of the body.

Metastasis

The spread of cancer cells from one part of the body to another.

Oncogenes

Genes that promote cell growth and division.

Proto-oncogenes

Normal genes that can become oncogenes if mutated.

Tumor-suppressor genes

Genes that inhibit cell growth and division.

Aneuploidy

An abnormal number of chromosomes.

Translocation

The movement of a segment of DNA from one chromosome to another.

Duplication

The presence of an extra copy of a segment of DNA.

Deletion

The absence of a segment of DNA.

Inversion

The reversal of a segment of DNA within a chromosome.

Clonal evolution

The process by which a population of cells acquires mutations that allow them to grow and divide more rapidly.

Loss of heterozygosity

The loss of one copy of a tumor-suppressor gene, leading to increased cancer risk.