Download Genetics Vocabulary

Genetics Vocabulary
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Inherited trait — A characteristic that makes one person different from another. Eye color and height are traits. For every inherited
trait, you have two genes, one from each parent.
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Cells — The microscopic, living building blocks from which every living thing is comprised. The human body is composed of over 75
trillion cells.
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Nucleus — A membrane-bound structure within a cell that contains the genetic information that the cell needs to grow and divide.
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Gene — A section of a chromosome, made up of DNA.A given gene provides the information that a cell needs to create a specific
protein.
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Genetics — The scientific study of heredity, including the structure and function of genes.
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Heredity — The characteristics you get from your parents.
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Chromosomes — A rod-like structure of tightly coiled DNA found in the cell nucleus of plants and animals. Chromosomes are
normally found in pairs; human beings typically have 23 pairs of chromosomes.
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Gregor Mendel — (1822–1884) The Austrian monk who bred pea plants and discovered in 1865 that traits are controlled by
genes. His work became the basis for modern genetics and the study of heredity.
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Phenotype — Physical appearance of an organism (e.g. tall, short). Usually the appearance of the dominant gene, or the recessive if it
is a purebred trait.
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Genotype — The genetic makeup of an organism.
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Dominant gene — A specific sequence of DNA that contains information which determines a given trait for an organism.
Dominant traits, like brown eye color, overcome recessive traits, like blue eye color.
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Recessive gene — A specific sequence of DNA that only determines a given trait when found twice in a gene pair.
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Cross — Mating of two organisms.
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Purebred — Organism with identical genes for a trait.
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Hybrid — Organism with different genes for a trait.
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Reginald Punnett — (1875–1967) English geneticist who discovered some basic principles of genetics by studying poultry and
sweet peas.
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Punnett square — A chart that shows all possible gene combinations in across of parents whose genes are known.
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Protein — A large complex molecule made up of one or more chains of amino acids. Proteins perform a wide variety of activities in the
cell.
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DNA — (deoxyribonucleic acid) A specialized molecule that contains the genetic information that allows characteristics to be passed
from parents to offspring. The information contained in the DNA molecule provides a “blueprint,” or a set of codes, for building other
molecules used by the cell.
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Meiosis — The process of cell division resulting in the formation of egg and sperm cells with half the amount of genetic material as
other cells.
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Gamete — (egg, sperm) Specialized cell that contains half of the genetic information found in most cells.
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Mutation — A change in the genetic code of an organism. Some may be beneficial for an organism; others may be lethal, but the
majority go unnoticed.
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Variations — Small differences in characteristics among animals of the same species, brought about by genetic mutations