Students in seventh grade can learn about the important relationship between genotypes and phenotypes. Genotypes are genes that provide the code information for a cell to produce proteins. Phenotypes are an observable characteristic produced by a specific genotype. Flower color is a good example to post on a bulletin board. Color is the result of protein pigments that produce the variety of colors in flowers. Students can be invited to consider other observable traits in addition to flower color, including hair color, eye color and blood types.
Gregory Mendel performed one of the more important works in genetic research during the 19th century. His research provided important knowledge that living organisms contained two copies of each gene, and one gene can be dominant to another gene. Cross-mating pea plants revealed that recessive traits could hide from observable phenotypes when an organism possessed one dominant and one recessive gene, or heterozygous. The recessive trait resurfaced as a phenotype when plants both heterozygous for the trait were cross-pollinated. Mendel's work remains one of the main topics in basic education. The bulletin board could show the results of Mendel's work, including flower color, seed color and whether seed shapes were round or wrinkled comparing genotypes with the observable phenotypes.
Inheritance is another key aspect of genetics brought to light by Charles Darwin during the 19th century. The basic premise for Darwin evolution is that organisms possess phenotypic traits that improve the ability to survive. It is a natural selection of survival traits called "survival of the fittest." The color of moths is a textbook example. Dark-colored moths are hidden from bird predators in a polluted forest while light-colored moths are easily seen. Nature selects the darker moth for survival because they are hidden from potential predators. A bulletin board could show the moth color example and other known survival traits.
In 1953, Watson and Crick pieced together the biochemical structure of genetic material, DNA, and presented a model for DNA replication. The discovery was remarkably important to genetic sciences and is an important topic for a seventh-grade bulletin board on genetics. The board can show a picture view of the double-stranded DNA molecule showing the repetition of four nitrogenous bases designated as A, G, C and T. Also important is the method of replication for DNA. DNA is double-stranded whereas A always matches with T and G always matches with C. The double strands separate during replication and are replaced with matching bases to produce two identical strands. Each newly replicated double strand of DNA contains one parental strand and one new strand.
Work provided by Mendel, Darwin, Watson and Crick led to future development in genetics research. Presently, science has determined the entire content of DNA in humans equivalent to 9 billion repeating nitrogenous base units of A, G, C and T. Including technology on a seventh-grade bulletin board can spark interest in promising, young genetic researchers. Automated sequencing equipment, next-generation sequencers and polymerase chain reaction are all strong topics for a bulletin board. Students can understand that these technologies exist and are used in important genetics research today.
The importance of genetics research in medicine is also a prime topic for a seventh-grade bulletin board. Genetics research is currently used for detection and treatment of inherited diseases, such as Alzheimer's, diabetes and cancer. Capacity to determine the entire sequence of humans provides a norm for comparison with genetic abnormalities that cause certain diseases. A bulletin board can present some medical research studies designed for the seventh-grade student. Genetics is a fascinating topic and a field that is evolving very quickly. A well-presented bulletin board can spark interest in students in junior high school.