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Biology Ch 6 Vocab
Term | Definition |
---|---|
Somatic cells | Also called body cells, make up most of your body tissues and organs. |
Gametes | Sex cells. |
Homologous chromosomes | Two chromosomes that are exactly the same. |
Autosomes | Chromosome pairs 1 through 22. |
Sex chromosomes | Chromosomes that directly control the development of sexual characteristics. |
Sexual reproduction | The fusion of two gametes that results in offspring. |
Fertilization | The fusion of an egg and a sperm cell. |
Diploid | Means a cell has two copies of each chromosome. |
Haploid | Means that a cell has only one copy of each chromosome. |
Meiosis | A form of nuclear division that divides a diploid cell into haploid cells. |
Gametogenesis | The production of gametes. |
Sperm | The male gamete. |
Egg | The female gamete. |
Polar bodies | Cells with little more than DNA that are eventually broken down. |
Traits | Distinguishing characteristics that are inherited, such as eye color, leaf shape, and tail length. |
Genetics | The study of biological inheritance patterns and variation in organisms. |
Purebred | Genetically uniform. |
Cross | The mating of two organisms. |
Law of segregation | Mendel's first law. |
Gene | A piece of DNA that provides a set of instructions to a cell to make a certain protein. |
Allele | Is any of the alternative forms of a gene that may occur at a specific locus. |
Homozygous | Describes two of the same alleles at a specific locus. |
Heterozygous | Describes two different alleles at a specific locus. |
Genome | All of an organism's genetic material. |
Genotype | The genetic makeup of a specific set of genes. |
Phenotype | The physical characteristics of an organism. |
Dominant allele | The allele that is expressed when two different alleles or two dominant alleles are present. |
Recessive allele | The allele that is only expressed when two copies are present. |
Punnett square | A grid system for predicting all possible genotypes resulting in a cross. |
Monohybrid crosses | Crosses that examine the inheritance of only one specific trait. |
Testcross | A cross between an organism with an unknown genotype and an organism with the recessive phenotype. |
Dihybrid crosses | Crosses that examine the inheritance of two different traits. |
Law of independent assortment | States that allele pairs separate independently of each other during gamete formation, or meiosis. |
Probability | The likelihood that a particular event will happen. |
Crossing over | The exchange of chromosome segments between homologous chromosomes during prophase 1 of meiosis 1. |
Genetic linkage | Genes located close together tend to be inherited together. |