Biology EOC Words for Pages 64-80, Teacher Key
Codominance- when both alleles of a gene are fully expressed. Ex- brown and white chicken mate and
the chicks come out speckled or brown and white. There isn’t one more dominant than the other.
Autosomes- chromosomes 1-22, they occur in your somatic cells / body cells. They are responsible for
everything but your sex.
Double Helix- DNA molecule, two strands twisted around each other like a winding staircase.
Nucleotides- sub-units that make up DNA. Has three parts: phosphate group, 5-carbon sugar, and
nitrogenous base.
DNA replication- Process of making a copy of DNA.
Mutation- A change in the DNA of a gene.
Inversion Mutation- a chromosome piece reattaches to the original chromosome but in a reverse
orientation or direction.
Deleted Mutation- segments of a gene are lost, often during meiosis. A deletion changes the number of
DNA bases by removing a piece of DNA. Small deletions may remove one or a few base pairs within a
gene, while larger deletions can remove an entire gene or several neighboring genes. The deleted DNA
may alter the function of the resulting protein(s).
Point Mutation- a single nucleotide changes.
Insertion Mutation- a sizeable length of DNA is inserted into a gene. An insertion changes the number of
DNA bases in a gene by adding a piece of DNA. As a result, the protein made by the gene may not
function properly.
Duplication Mutation- A duplication consists of a piece of DNA that is abnormally copied one or more
times. This type of mutation may alter the function of the resulting protein.
Translocation Mutation- piece of a chromosome reattached to a non-homologous chromosome.
Chromosome segments, and the genes they contain, change positions.
Messenger RNA- Form of RNA that carries genetic information from the nucleus to the cytoplasm and
acts as a template for protein synthesis.
Transfer RNA- Form of RNA that brings amino acids to ribosomes during protein synthesis.
Ribosomal RNA- RNA that is in the ribosome and guides the translation of mRNA into a protein. Cells
protein factories.
Gene Expression- proteins are made based on the information encoded in DNA. Also known as protein
synthesis.
Translation- process that converts or translates a mRNA message into a polypeptide (one or more
makes up a protein).
Transcription- process of copying a sequence of DNA to produce a complimentary strand of RNA.
Protein Synthesis- proteins are made on the information encoded in DNA= gene expression.
Codon- sequence of three nucleotides that codes for an amino acid. Ex- AUG= methione, CUU= leucine
Genotype- Genetic make-up or set of alleles that an individual has for a characteristic.
Phenotype- Physical make-up or traits that results from a set of alleles.
Polygenic Inheritance- several genes affect one characteristic.
Sex linked- alleles are located only on the X and Y chromosome.
Incomplete dominance- when an offspring has a phenotype between that of its parents. Ex- Red and
white flowers make pink flowers.
Frameshift Mutation- mutation that involves the insertion or deletion of a nucleotide in the DNA
sequence. Causes a gene to be read in the wrong three nucleotide sequence. Ex- The Cat Ate = The Ata
te (remove the C)