|amino acids 20 molecules that contain nitrogen and together form the building blocks of proteins.
base pairs a set of two bonded nucleotides on opposite strands of DNA.
chromosome a rod
shaped structure of tightly coiled DNA found in the cell nucleus of plants and animals.
cloning the process used to make genetically identical copies of an organism.
cytoplasm substance within the cell but outside the nucleus in which various cell parts are suspended.
DNA deoxyribonucleic acid, the genetic material of cells that carries their genetic code.
gamete an organisms sex cell, which contains half the total number of chromosomes.
gene a section of a chromosome made up of DNA, the fundamental unit of heredity.
gene markers landmarks for a particular gene, either detectable traits that are inherited along with the gene or distinctive segments of DNA.
gene mapping the process of determining the positions of genes on a chromosome and the distance between them.
gene therapy the treatment of disease by replacing or changing non
genetics the scientific study of heredity.
genome all the genetic material in the chromosomes of a particular organism.
genome map a chart that shows the arrangement of the genes or other DNA markers on the chromosomes.
genotype the inherited genetic code of an organism for a specific trait.
helix a winding shape, similar to a spiral; the DNA molecule has a double
helix shape, which is two helixes twisted around each other.
human genome the collection of genes needed to produce a human being.
Human Genome Project the international research effort to identify and map all the genes in the human body.
inherit to receive a trait from an ancestor.
meiosis the division of the genetic information in reproductive cells, so that they have only half the normal number of chromosomes.
molecule a combination of atoms, and also the basic building
block of DNA and RNA. Each molecule has its own shape and attaches only to certain other molecules to form the DNA helix.
mutation a change in the genetic code that can occur because of environmental reasons or over long periods of time as part of evolution.
nucleotide a unit of DNA or RNA, consisting of one chemical base plus a phosphate molecule and a sugar molecule.
nucleus the center of a cell, where all of the DNA, packaged in chromosomes, is contained.
phenotype an organisms inherited physical appearance.
polymerase chain reaction a genetic engineering technique used to reproduce segments of DNA millions of times; it is used in forensics and chemical and biological experiments.
protein a chain of amino acids; examples include hormones, enzymes, and antibodies.
ribosome an organelle that produces protein in cells.
RNA ribonucleic acid, similar to DNA, except that it has ribose instead of deoxyribose sugar, and uracil instead of thymine as a nitrogen base.
sex chromosomes chromosomes that determine an organisms sex. Human females have two X chromosomes; males have one X chromosome and one Y chromosome.
somatic cells all body cells, except for the reproductive cells.
trait an organisms physical feature, determined by a gene.