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Polymerase chain reaction PCR - Animation

By: HWC, Views: 1594

Polymerase chain reaction (PCR) is a method that amplifies fragments of DNA. The purpose of PCR is to create copies of a specific region of DNA. To use this technique, researchers must know the base sequences at either end of the region of interest. They use this information to create...

The life cycle of protein

By: HWC, Views: 7351

The life cycle of a typical protein begins with its synthesis on a ribosome. As the polypeptide chain grows, molecules of a chaperone protein bind along its length. This prevents misfolding of the nascent polypeptide. ATP binding causes chaperone release. For most proteins, the polypeptide th...

DNA Replication

By: HWC, Views: 4588

DNA replication is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules. Replication is an essential process because, whenever a cell divides, the two new daughter cells must contain the same genetic information, or DNA, as the parent cell.

Peptide Bond Formation Animation

By: HWC, Views: 1545

During protein synthesis, peptide bonds link amino acids together in the order specified by DNA instructions. In this case, the first two amino acids in the protein are methionine and alanine. Here are ball-and-stick models of these amino acids. Peptide bond formation is a type of condensatio...

Proteins

By: HWC, Views: 6769

Living things must accomplish a great number of tasks just to get through a day, and these tasks are accomplished by a diverse range of biological molecules. In the range of tasks that molecules accomplish, however, proteins reign supreme. Almost every chemical reaction that takes place in living...

Chemical Equilibrium between N2O4 (colorless gas) and NO2 (brown gas)

By: HWC, Views: 6966

For a system at equilibrium: ◆ both forward and reverse reactions are occurring simultaneously ◆ rate of forward reaction must equal rate of reverse reaction OR Rate forward = Rate reverse ◆ concentrations of reactants and products remain constant with time the equilibrium positio...

Chloroplast Structure & Light Dependent Reactions (Photosystem 1 and 2 Cyclic Electron Flow)

By: HWC, Views: 7298

The leaf is the principle photosynthetic organ of the plant. This is a cross section of a leaf. The rectangular-shaped cells are part of the photosynthetic tissue called the palisade mesophyll. Each photosynthetic cell can contain several hundred organelles known as chloroplasts. The chlorop...

Anaphylaxis Animation

By: Administrator, Views: 10481

Anaphylaxis is a serious, life-threatening allergic reaction. The most common anaphylactic reactions are to foods, insect stings, medications and latex. If you are allergic to a substance, your immune system overreacts to this allergen by releasing chemicals that cause allergy symptoms.

What are the Parts of a Plant Cell?

By: HWC, Views: 6774

Every chloroplast in a plant cell is packed with stacks of flattened sacs called thylakoids. The thylakoid membranes contain chlorophyll, as well as most of the other components required for the light reactions of photosynthesis. The chlorophyll-containing structures within the membranes are c...