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Hydrogen bonds - role in the body

By: HWC, Views: 8012

A hydrogen bond is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. This is not a sharing of electrons, as in a covalent bond. Instead, this is an attraction between the positive and negative poles of charged atoms. ...

Role of ATP in muscle movement

By: HWC, Views: 7817

• Muscle cells use ATP to power contraction and movement. • The hydrolysis of ATP to ADP releases • ATP can be regenerated by adding to ADP. • During muscular contraction, ATP molecules: • Energize the myosin head • Detach myosin from actin • ATP must be then regenerat...

Condensation and Hydrolysis Animation

By: HWC, Views: 1558

A condensation reaction joins two molecules together to form one larger molecule. An enzyme removes a hydroxyl group from one molecule and a hydrogen atom from another, then speeds the formation of a bond between the two molecules at their exposed sites. Typically the discarded atoms join t...

Acids and bases - definition

By: HWC, Views: 7616

Acids and bases are found all around your house. For example, if you open your pantry or refrigerator, you might see a lot of acids. Fruit juice, soda pop, vinegar, and milk are all examples of acids. The word acid actually comes from a Latin term meaning ''sour.'' Many materials, like sugar for ...

Role of the respiratory system - effect of altered ventilation rates

By: HWC, Views: 7580

• Dissociation of the chemical substances in the body fluids can result in the production of free hydrogen ions. • The pH scale is used to measure the concentration of hydrogen ions in solution. • Normal blood pH values vary around 7.4. • When hydrogen ion concentration increases, t...

DNA close up Animation

By: HWC, Views: 1650

A section from a DNA double helix The backbone of each DNA strand consists of alternating deoxyribose sugars and phosphate groups. The two strands run in opposite directions. One runs from the 5' to 3' direction, the other in the 3' to 5' direction. Think of the deoxyribose units o...

Role of the urinary system - acidosis and alkalosis

By: HWC, Views: 7948

• Tubular cells of the proximal convoluted tubule and collecting tubules can alter filtrate pH and therefore blood pH. • These cells can affect blood pH with two coupled mechanisms: • Reabsorption of bicarbonate ions. • Secretion of hydrogen ions. • The reabsorption of bicarbonate...

The Krebs Cycle Animation

By: HWC, Views: 1927

The second-stage reactions of aerobic respiration. The second-stage reactions occur in a mitochondrion's inner compartment. In the first preparatory reaction, a carbon atom is stripped from pyruvate and released as carbon dioxide. The remaining carbons combine with coenzyme A and give ...

Splitting of Sugar, Oxidation/ Reduction & ATP Generation

By: HWC, Views: 7476

The next reaction shows us the meaning of "glycolysis" or the splitting of glucose. The fructose bisphosphate molecule is split into two molecules each containing 3 carbons as the backbone. FBP is split into two 3-carbon molecules called G3P, or glyceraldehyde 3-phosphate. Notice that the phos...