Heredity-Study Guide

threadlike structure within the nucleus containing the genetic information that is passed from one generation of cells to the next. >Instructions from the genes determine traits.

Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring. Chemical found within each chromosome. Arranged like a sequence of recipes in code, it directs the activities of the cell. It is a spiral-shaped molecule that is a long, twisted strand of material.

the passing of genetic traits from parent to offspring

the study of heredity--the study of how traits are inherited from parents to offspring

a characteristic that an organism can pass on to its offspring through its genes

the breeding of a male and female based on the most desirable traits of each parent to produce offspring with those traits (Example: Dogs--6000-7000 B.C., Egyptians developed Saluki dogs)

genetic engineering, redesigns or changing the make-up of an organism; The use of technology to alter or improve living things, such as plants that resist disease, in order to benefit people. Scientists can use this to create super-plants, oil-eating bacteria, and drugs similar to natural substances found in the human body. Such advances can help increase the world food supply, clean up pollution, and fight disease. >Cloning >Gene machines >Gene splicing

A technique by which a cell or organism is grown directly form one parent. A clone is genetically identical to its parent. Scientists use cloning to make medicines and new types of plants.

Genes from two different species are joined. Gene splicing is used to make drugs and to develop plants that are resistant to disease or drought. Scientists use bacteria for the production of many new drugs such as insulin. A gene from a human is added to a DNA structure inside bacteria. Every time the bacteria reproduce, they make more copies of the human gene.

different ways a certain trait appears

The gene that blocks the effect of another gene for the same trait.

The gene whose effect is blocked, or hidden, by a dominant gene. For example, in pea plants, the gene for shortness is recessive.

An organism that receives two dominant or two recessive genes for a trait

An organism that receives one dominant and one recessive gene for a trait

A diagram that shows all of the possible gene combinations for a trait that can be expected to show up in the offspring. It has four boxes and each box has a possible combination of genes for one inherited trait form each parent.

>Genes make up a chromosome. If a chromosome is a chain, each link in the chain is a gene. The 46 chromosomes in a human cell contain about 100,000 genes. >Genes tell cells what functions they will perform. >Genes determine physical traits such as hair color, eye color, and shape of the earlobe >Genes also determine body structure such as height, shape of head, facial features >Every cell in your body has the exact same genes

He was an Austrian monk who loved gardening, science, and mathematics. He combined these interests in a study of pea plants. Mendel noticed trait variations in pea plants--some were tall; others were short. He believed that such variations were due to traits passed on from generation to generation. He designed pea plant experiments to test his ideas.