Glossary

• The 4 bases are Adenine, Thymine, Cytosine, Guanine
• Alleles are different versions of the same gene.
• Autosomes are chromosomes that are not sex chromosomes.
• Carcinogens are mutations that cause cancer
• Centrometre is where 2 chromatids are joined together
• Chromatid: One of the strands of a chromosome following replication (Interphase)
• DNA is made of Phosphate, Deoxyribose sugar and one of 4 bases (A,T,C,G)
• The gametes are the sperm and egg
• Gene: A section of DNA that carries the genetic code for a characteristic
• Genome: The complete set of DNA
• Dominant: The allele is dominant to the other. Can block recessive allele.
• Recessive=The allele is not represented and the dominant. Recessive will only come if it is homozygous recessive (2 recessive alleles)
• Homozygous: 2 identical alleles on homologous chromosomes
• Heterozygous: Having 2 different alleles on homologous chromosomes
• Meiosis: Cell division that produces 4 gametes with half chromosomes of the parent cell
• Mitosis: Cell division that produces 2 daughter cells identical to the parent cell
• Mutagen: An agent that causes mutation
• Nucleotide: The building blocks of DNA. Made of Phosphate, Deoxyribose sugar and one of 4 bases (A,T,C,G)
• Pathogen: A disease-causing organism
• Phenotype: The observable characteristics of the individual
• Genotype= The collection of alleles we have. Letters for the gene: Capitals are dominant, lower case is recessive (Big R, Little r)
• Recessive Trait: The trait that is hidden in heterozygous individuals and is only expressed when homozygous recessive
• Somatic Cells: All cells except reproductive cells
• Sex-linked genes: Genes present on the sex chromosomes