Regulation of Gene Expression & Biotechnology Vocabulary

Housekeeping Genes

Genes that are switched on all the time because *they are needed for life functions* vital to an organism (like the genes needed for cell respiration)

Vertical Gene Transfer

Occurs during reproduction between generations of cells

Determination

Things or processes necessary to commit a cell to a particular type of cell. Cytoplasm Determinants Neighboring Cells (Cause)

Sex Pilus

A structure on the cell wall that allows one bacterium to adhere to another prior to conjugation.

Totipotent

Cells that are able to develop into *any* type of cell found in the body.

Pleuripotent

Cells that can become any/all cell types *except* of tissues needed to support the growth of a fetus such as a placenta

Repressor

*A protein that binds to an operator* and physically blocks RNA polymerase from binding to a promoter site

Genome

*All* the genetic information in an organism

Operon

*Group of genes* operating and transcribed together with the help of other proteins

Cleavage

*Rapid mitosis* (cell division) without growth of daughter cells. The whole remains the same size but each cell gets smaller.

CpG Island

A *Cytosine and Guanine* rich region of DNA

Transposed Genes

A gene that was *copied to another chromosome*

Polymerase Chain Reaction

A method of producing thousands of copies of DNA segment using the enzyme DNA polymerase

Electrophoresis

A process where DNA fragments are separated according to size using electrical charges

Promotor

A region of DNA with a specific sequence that tells RNA polymerase where to *begin transcription*. (Ex. TATA Box)

Transcription Factor

A regulatory *protein* that binds to DNA and *affects transcription of specific genes*.

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

Lytic Cycle

A type of viral (phage) replication cycle resulting in the release of new phages by lysis (and death) of the host cell.

Bacteriaphage

A virus that infects bacteria

Gene Regulation

Ability of an organism to *control which genes are transcribed* in response to the environment

Gene Amplification

An *increase in the number of copies* of a particular segment of DNA

Reverse Transcriptase

An enzyme used in retroviruses that performs transcription in the opposite direction.RNA -> DNA.

Repressible Operon

An operon under negative control. It is *usually "on" but can be turned "off"*.

Inducible Operon

An operon under positive control. It is *usually "off" but can be turned "on"*.

Modulator

Binds to the allosteric site of a repressor to activate or deactivate it.

Specialized Genes

Code for proteins needed for a particular *cell type* or particular function

Regulator Gene

Codes for the production of the *repressor protein*. Upstream of Operator.

Transcription Factors

Collection of proteins that *mediate the binding of RNA polymerase* and the initiation of transcription.

Acetylation

Decreases the affinity of histones for DNA *making DNA more accessible* for transcription

Hershey-Chase Experiment

Determined that DNA is the genetic material using radioactive bacteriaphages and bacteria

DNA sequencing

Determining the exact order of the base pairs in a segment of DNA.

Restriction Enzymes

Enzyme that cuts DNA at a specific sequence of nucleotides

Structural Genes

Genes that *code for proteins* in an operon

Blastula

Hollow ball of cells

Methylation

Increases the affinity of histones for DNA *making DNA more accessible* for transcription

Biotechnology

Manipulation of natural biological processes in order to serve societal needs.

Capsid

Outer protein coat of a virus

Mitosis

Part of eukaryotic *cell division* during which the cell *nucleus divides*

Epigenetics

Process of influencing gene expression due to stimulus. DNA remains unchanged.

Apoptosis

Programmed *cell death*. Occurs in infected cells, development (picture), in cells that are no longer functional

Transposition

Small DNA segments are *transferred* from one chromosome to another.(Cut/Paste or Copy/Paste)

Gene Loss

Somatic cells *lose*/have less chromosomes than gametes

Alternative Splicing

Splicing of introns in a pre-mRNA that occurs in *different* ways, leading to *different* mRNAs that code for *different* proteins.

Griffith's experiment

Suggesting that bacteria are capable of transferring genetic information through a process known as transformation

Morphogenesis

The *development of the form* of an organism and its structures

Conjugation

The *direct transfer of DNA* between two cells that are temporarily joined. Typically by a sex pilus

Differential Gene Expression

The *expression* of *different* sets of *genes* by cells with the *same genome*.

Operator

The *on and off* switch of an operon

Transposons

The DNA segment that's been *transposed*.

Genetic Engineering

The direct manipulation of genes for practical purposes.

Cell Differentiation

The process by which a *cell becomes specialized* for a specific structure or function. (Effect)

Gene Expression

The process by which a gene produces its product and the product carries out its function

Bacterial Transformation

The process by which bacterial cells take up DNA molecules

Gastrulation

The process in which a gastrula develops from a blastula by the *inward migration of cells*

Prophage

The viral DNA that is embedded in the host cell's DNA

Horizontal Gene Transfer

Transfer of genes between cells of the same generation: transformation, transduction, conjugation, and transposition.

Retrovirus

Use reverse transcriptase to copy their RNA genome into DNA

Lysogenic Cycle

Viral reproductive cycle in which the viral DNA is added to the host cell's DNA and is copied along with the host cell's DNA

Transduction

Viruses carrying prokaryotic genes from one bacterium to another

Transformation

When a cell takes in *foreign* genetic material and *incorporates it into its own*.