Bio 30 Unit 3C_ Genetics - Molecular

Griffith's transformation experiment

An experiment conducted by Frederick Griffith in 1928 that demonstrated the process of transformation in bacteria.

The Hershey-Chase experiment

A series of experiments conducted by Alfred Hershey and Martha Chase in 1952 to prove that DNA, and not protein, is the hereditary material.

DNA structure

Double helix structure, consisting of a sugar-phosphate backbone and nitrogenous base pairs.

Semiconservative replication

The process of DNA replication where each new molecule of DNA contains one strand from the original DNA molecule.

The Meselson-Stahl experiment

An experiment that proved the semiconservative nature of DNA replication.

Chargaff's Rule

The rule that states that DNA from any cell of an organism should have a 1:1 ratio of purines and pyrimidines, and the amount of guanine must equal the amount of cytosine, and the amount of adenine must equal the amount of thymine.

Nucleotide

The basic building block of DNA, consisting of a phosphate molecule, a sugar molecule, and a nitrogenous base.

5' and 3' ends of nucleic acids

The two ends of a DNA or RNA molecule

DNA polymerase

An enzyme involved in DNA replication that adds new nucleotides to the growing DNA strand.

Helicase

An enzyme that unwinds and separates the DNA strands during DNA replication.

Primase

An enzyme that synthesizes a primer sequence to initiate DNA replication.

Ligase

An enzyme that splices together Okazaki fragments of the lagging strand during DNA replication.

Transcription

The process of synthesizing mRNA from a DNA template.

Translation

The process of synthesizing a protein from an mRNA template.

tRNA

Transfer RNA, a type of RNA molecule that carries amino acids to the ribosome during translation.

rRNA

Ribosomal RNA, a type of RNA molecule that forms part of the ribosome and is involved in protein synthesis.

Codons

Three-nucleotide sequences on mRNA that specify the amino acids to be incorporated into a protein during translation.

Anticodons

Three-nucleotide sequences on tRNA that are complementary to the codons on mRNA during translation.

Gene Expression

The process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein.

Gene Expression

The process by which a segment of DNA is transcribed into mRNA and then translated into a protein.

Central Dogma

The concept that describes the flow of genetic information from DNA to mRNA to protein.

Transcription

The process of copying the information in a segment of DNA into a single strand of mRNA.

mRNA

Messenger RNA, a single-stranded molecule that carries the genetic information from DNA to the ribosomes for protein synthesis.

Translation

The process of converting the mRNA sequence into a sequence of amino acids to form a protein.

Codon

A sequence of three nucleotides on the mRNA that codes for a specific amino acid.

tRNA

Transfer RNA, a molecule that carries the specific amino acids to the ribosomes during translation.

Ribosome

The cellular structure where protein synthesis occurs, composed of rRNA and protein subunits.

Exons

The RNA sequences that code for proteins.

Introns

The RNA sequences that do not code for proteins and are removed during RNA processing in eukaryotes.

Antisense Strand

The DNA strand that is complementary to the sense strand and serves as the template for transcription.

Sense Strand

The DNA strand that has the same sequence as the mRNA, except for the substitution of T with U in RNA.

Amino Acids

The building blocks of proteins, linked together in a specific sequence determined by the mRNA codons.

Point Mutation

A mutation that involves a change in a single nucleotide in the DNA sequence.

Frameshift Mutation

A mutation that involves the insertion or deletion of nucleotides, causing a shift in the reading frame of the mRNA.

Silent Mutation

A mutation that does not change the amino acid sequence due to the redundancy of the genetic code.

Missense Mutation

A mutation that changes one amino acid in the protein sequence.

Nonsense Mutation

A mutation that introduces a premature stop codon, resulting in a truncated protein.

Somatic Cells

Body cells that are not passed on to offspring and can develop mutations that may lead to diseases like cancer.

Germ Line Cells/ gametes

Reproductive cells that can pass on mutations to offspring.

Point Mutation

A chemical change that affects just one or a few nucleotides, involving the substitution of one nucleotide for another.

Frameshift Mutation

An insertion or deletion of a nucleotide that causes the entire reading frame of the gene to be altered.

Silent Mutations

Mutations that have no effect on the cell's overall functioning.

Missense Mutations

Mutations that lead to a slightly altered but still functional polypeptide.

Nonsense Mutations

Mutations that render the gene unable to code for a functional polypeptide.

Mitochondrial DNA

DNA stored in the mitochondria and inherited only from the mother.

okazaki fragments

short segments of DNA formed during DNA replication on the lagging strand.

RNA Primer

Short segment of RNA that serves as a starting point for DNA replication.

purine

A nitrogenous base found in DNA and RNA, consisting of a double-ring structure. It is one of the two types of nucleotide bases, along with pyrimidine.

Double ring structure

In DNA and RNA, the structure refers specifically to adenine and guanine, which are purine bases. It plays a crucial role in the formation of the genetic code and the stability of the nucleic acid molecule.

sense & antisense strands

One strand of DNA is called the sense strand because when you read it in the right direction it provides the code to make a protein. In two-stranded DNA, the sense strand is bonded to an opposite DNA strand which is called the antisense or noncoding strand.

restriction endonuclease

An enzyme that recognizes specific DNA sequences and cuts the DNA at those sites. Used in genetic engineering for DNA manipulation and analysis.

complementary strands

The two DNA strands that have matching base pairs.

supplementary strands

the strand that pairs with the original strand during DNA replication. They are formed by adding nucleotides that are complementary to the original strand.

non-parallel strands

DNA structure where the two strands are not aligned in the same direction (DNA double helix)

Semi-conservative replication

DNA replication process where each new DNA molecule consists of one original (parental) strand and one newly synthesized (daughter) strand.

amino acids

building blocks of a protein

plasmid

A small, circular, double-stranded DNA molecule that can replicate independently in a host cell. commonly found in bacteria and can be used in genetic engineering to introduce new genes into cells.