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The Cell: High School Biology

The Cell: High School Biology

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Genetics Alive!- Explore Genes and Genomes (An Analogy) What is a gene? (An analogy) Every living organism on earth has a genome that is unique to that organism. However, all of the genomes are made of the same basic material. Cell Structure All living organisms on Earth are divided into cells. The main concept of cell theory is that cells are the basic structural unit for all organisms. Cells are small compartments that hold the biological equipment necessary to keep an organism alive and successful. Living things may be single-celled or they may be very complex such as a human being. There are smaller pieces that make up cells such as macromolecules and organelles.

Parts of the Cell Do All Cells Look the Same? Cells come in many shapes and sizes. Some cells are covered by a cell wall, other are not, some have slimy coats or elongated structures that push and pull them through their environment. Some cells have a thick layer surrounding their cell. This layer is called the capsule and is found in bacteria cells.

Solve the Outbreak App Download & Get Started Today! Scientists and experts from across CDC have put their expertise and know-how into developing a realistic, exciting app that turns your mobile tablet into its own version of CSI. Download the free app today! A-level Biology/Cells Cell Organelles[edit] Organelles are parts of cells. Each organelle has a specific function. 1. Nuclear membrane 2.

Paleoclimatology: The Oxygen Balance : Feature Articles As air cools by rising into the atmosphere or moving toward the poles, moisture begins to condense and fall as precipitation. At first, the rain contains a higher ratio of water made of heavy oxygen, since those molecules condense more easily than water vapor containing light oxygen. The remaining moisture in the air becomes depleted of heavy oxygen as the air continues to move poleward into colder regions.

How to Create a Chromosome Map Recombination: During crossing-over (prophase I of Meiosis), genes on chromosomes switch places. Crossover is random, but the likelihood that 2 genes crossover will increase if those genes are farther apart. Genes closer together are more likely to "stick together" and not switch places. Gene Linkage Maps: Using the crossover frequencies, you can construct a map to represent the distances between genes. This map shows chromosome #2 of Drosophila melanogaster.

Diffusion, osmosis and active transport Substances are moving in and out of the cells of your body all the time. To understand why the water balance is so important in homeostasis, and to make sense of how your kidneys work, you need to know about diffusion, osmosis and active transport. is the spreading out of the particles of a gas or any substance in solution.

The race to sequence the human genome - Tien Nguyen The Human Genome Project was a massive undertaking that began as an idea put forward by prominent scientists in the 1980s. For a complete timeline of the Project from start to finish, click here. The DNA database to which the Human Genome Project was uploading their sequenced data is still freely available online and can be found here. Fred Sanger won the 1980 Nobel Prize in Chemistry for his contribution to the Sanger method, which was used by both the Human Genome Project and Celera. This sequencing technique involves making many copies of DNA in a test tube. Each copy is one letter longer than the last and is capped by a fluorescently labeled base: an A, T, G, or C. The DDT Story If there is a single pesticide almost everyone can name, it's DDT. DDT was one of the first chemicals in widespread use as a pesticide. Following World War II, it was promoted as a wonder-chemical, the simple solution to pest problems large and small. Today, nearly 40 years after DDT was banned in the U.S., we continue to live with its long-lasting effects: Food supplies: USDA found DDT breakdown products in 60% of heavy cream samples, 42% of kale greens, 28% of carrots and lower percentages of many other foods.

If the Moon Were Only 1 Pixel - A tediously accurate map of the solar system Mercury Venus Earth Differences between Eczema, Psoriasis, Couperose and Rosacea - Mario Badescu Skin Care Which skin condition do you have? Do you have areas of red skin, perhaps some dry, itchy skin or even blisters or rash? There are several skin conditions—Eczema and Psoriasis as well as Rosacea and Couperose—which share a number of characteristics and which are, in some cases, indistinguishable from each other.

This TED Talk Shows How Mucus Is There To Keep Us Healthy When you say mucus, most people automatically think of the stuff that comes out of a person’s nose when they're sick. That is true, however — as disgusting as mucus may seem — it is actually keeping us healthy. In a recent TED Talk, speaker Katharina Ribbeck explains the various ways our mucus is actually looking out for us. Our body produces more than a liter of mucus per day.