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7th Sci Ch. 4 Vocab
Question | Answer |
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Heredity | The passage of genetic instructions from one generation to the next generation. |
Trait | A specific characteristic that an organism can pass to its offspring through its genes. |
Genetics | The scientific study of heredity. |
Fertilization | The process in sexual reproduction in which an egg cell and a sperm cell join to form a new cell. |
Purebred | An offspring of many generations that have the same form of a trait. |
Gene | A sequence of DNA that determines a trait and is passed from parent to offspring. |
Allele | The different form of a gene. |
Dominant allele | An allele whose trait always shows up in the organism when the allele is present. |
Recessive allele | An allele that is hidden whenever the dominant allele is present. |
Hybrid | An offspring of crosses that has two different alleles for a trait. |
Probability | A number that describes how likely it is that a particular event will occur. |
Punnett square | A chart that shows all the possible combinations of alleles that can result from a genetic cross. |
Phenotype | An organism’s physical appearance, or visible traits. |
Genotype | An organism's genetic makeup, or allele combinations. |
Homozygous | Having two identical alleles for a particular gene. |
Heterozygous | Having two different alleles for a particular gene. |
Incomplete dominance | A situation in which one allele is not completely dominant over another allele. |
Codominance | A situation in which both alleles for a gene are expressed equally. |
Multiple alleles | Three or more possible alleles of a gene that determine a trait. |
Polygenic inheritance | The inheritance of traits that are controlled by two or more genes, such as height in humans. |
Meiosis | The process that occurs in formation of sex cells [sperm and egg] by which the number of chromosomes is reduced by half. |