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| Allele | The alternative forms of genes having the same place in homologous chromosomes which influence the development of alternative traits or characters. |
| Anaphase | The phase in mitosis when chromatids separate and move toward opposite poles. In meiosis, the paired chromosomes move apart. |
| Anther | The saclike part of the stamen on seed-producing plants which develops and contains pollen. |
| Chromosome | A microscopic, dark-staining body, visible in the nucleus of the cell at the time of nuclear division, which carries the genes, arranged in linear order. Its number in any species is usually constant, and it serves as the bridge of inheritance, i.e., the sole connecting link between two succeeding generations. |
| Cross Pollination | Transfer of pollen between plants that are not of identical genetic material. |
| Dioecious | A plant that produces flowers that have either stamens or pistils, but not both on the same plant. |
| Diploid | Having one genome comprising two sets of chromosomes. Somatic tissues of higher plants and animals are ordinarily diploid in chromosome constitution in contrast with the haploid (monoploid) gametes |
| Dominant Gene | A gene that prevents its allele from having a phenotypic effect. |
| Egg | The reproductive body produced by a female organism: in animals, the ovum; in plants, the germ cell, which after fertilization, develops into the embryo. |
| Fertilization | Union of pollen with the ovule to produce seeds. |
| Filament | The part of the stamen of a flower that is below the anther and supports it. |
| Gamete | A “sex-cell,” capable of uniting with another gamete to produce a cell (fertilized egg, or zygote) that in turn is capable of developing into a new individual. |
| Gene | The simplest unit of inheritance. Physically, each gene is apparently a nucleic acid with a unique structure. It influences certain traits. |
| Genetics | The science that deals with the laws and processes of inheritance in plants and animals. |
| Genotype | The genetic constitution (gene makeup), expressed and latent, of an organism. Individuals of the same genotype breed alike. |
| Haploid | In genetics, this is half the number of chromosomes that are usually present in the nucleus; occurs during reduction division. |
| Heredity | Genetic transmission of traits from parents to offspring. |
| Heterozygous | Having two different genes at the same locus on a pair of homologous chromosomes. |
| Homozygous | Possessing identical genes with respect to any given pair or series of alleles. |
| Inheritance | The transmission of genetic factors from parent to offspring. |
| Interphase | The period in the life of a cell between mitotic divisions. |
| Meiosis | Cell division early in the reproductive process, and in the formation of pollen and ovule. Each pair of chromosomes in the cell being divided separates, and one member of each pair goes to each of the two new cells formed. |
| Meristems | Plant tissue capable of cell division and therefore responsible for growth. |
| Metaphase | The stage of cell division in which the chromosomes are arranged in an equatorial plate or plane. It precedes the anaphase stage. |
| Mitosis | Cell division involving the formation of chromosomes, spindle fibers, and the division of chromosomes by a process of longitudinal splitting. Each of the resulting daughter cells thus has a full set of chromosomes as distinguished from reduction division or meiosis, in which the daughter cells have half the somatic number. |
| Monoecious | Plants that have male and female sex organs in different flowers on the same plant, such as cucumbers and squash. |
| Nectar | A sweet secretion of flowers of various plants, used by bees to store as honey. |
| Nucleus | The central portion of the cell protoplast surrounded by a very thin membrane. It consists of nucleoplasm and includes within itself variously arranged chromatin, nuclear sap, and nutritive substances. It is of crucial significance in metabolism, growth, reproduction, and the transmission of the determiners of heredity characters. |
| Ovary | The portion of the pistil or carpel of a flower that contains one or more ovules. |
| Ovule | The body that, after fertilization, becomes the seed; the egg-containing unit of the ovary. |
| Petal | A division of a flower inside the calyx; a unit of the corolla, consisting of petioles, which usually surrounds the pistil and stamens. |
| Phenotype | The observed character of an individual without reference to its genetic nature. Individuals of the same phenotype look alike but may not breed alike. |
| Pistil | The female element of a flower; composed of stigma, style, and ovary. |
| Pollen | The male element that carries the spores in the fertilization of the egg nucleus in the ovule of a flower. The pollen is borne by the anthers and is usually a yellowish, dustlike mass of separate grains. |
| Pollen Grain | The anther or male part of the flower produces pollen grains that are the male sex cells. |
| Pollen Tube | Tube formed following the germination of a pollen grain, when the grain resides on the stigma of a flower. The tube carries the male gametes to the ovule. |
| Pollination | The transfer of the pollen from the anther to the stigma of a flower, the first step in producing a fruit or seed. |
| Prophase | The first phase of cell division wherein many of the preparatory steps takes place, such as shortening and thickening of the chromosomes, division of the centromeres, disappearance of the nuclear membrane, and formation of the spindle. |
| Recessive | In genetics, a gene or trait which is masked by a dominant gene. |
| Seed | The embryo of a plant; also kernels of corn, wheat, etc., which botanically are seed like fruits as they include the ovary wall. |
| Self-Pollination | The transfer of pollen from the anther to the stigma of the same flower or to flowers of the same plant or other plants of identical genetic material such as apple varieties, clones of wild blueberries, etc. |
| Sexual Propagation | Producing plants from seeds. |
| Stamen | The organ of a flower which bears the pollen (microspores) consisting of the stalk (filament) and the anther. |
| Stigma | The receptive surface of the female organ of a flower that receives the pollen. |
| Style | In the pistil of a flower, the part between the ovary and the stigma; if the style is lacking, the stigma is sessile on the ovary. |
| Telophase | The phase of cell division between anaphase and the complete separation of the two daughter cells; includes the formation of the nuclear membrane and the return of the chromosomes to long, threadlike and indistinguishable structure. |
| Zygote | A fertilized ovum or egg, it is the diploid cell formed from the union of the sperm with an ovum. |
