Search Results

Introduction to Macular Degeneration

By: Administrator, Views: 10618

Macular degeneration An incurable, age-related, progressive eye disease that affects more than 10 million Americans. Leading cause of blindness for those ages 55 and older. Macular degeneration For the first time, researchers have linked gene defects to macular degeneration. Could lead to ...

Miller's reaction chamber experiment Animation

By: HWC, Views: 1322

A simple diagram of Stanley Miller and Harold Urey's experimental apparatus. The lower portion of the apparatus was filled with water. The upper portion was filled with a mixture of gases that simulated the earth's early atmosphere. Examples are methane, ammonia, hydrogen and carbon dioxide. ...

Peptide Bond Formation Animation

By: HWC, Views: 1558

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...

Condensation and Hydrolysis Animation

By: HWC, Views: 1582

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...

Photosynthesis overview Animation

By: HWC, Views: 1806

Illustration of the interrelationships of the light-dependent and light-independent reactions of photosynthesis. The light-dependent reactions split water, and produce ATP and NADPH. Oxygen is a by-product of these reactions. ATP and NADPH, together with carbon dioxide, are reactants in ...

Mechanisms of capillary exchange

By: HWC, Views: 7894

■ The primary role of capillaries is to permit the exchange of nutrients and wastes between the blood and tissue cells (via interstitial fluid). ■ Oxygen and nutrients move from the blood to the cells. ■ Carbon dioxide and other wastes move from the cells to the blood. The three ba...

Digestive chemicals - types & enzymes

By: HWC, Views: 7728

• Chemical digestion breaks down food as it moves through the digestive tract. • Using enzymes and other digestive chemicals, the process reduces food particles into nutrient molecules that can be absorbed. • Most chemical digestion is done by the actions of digestive enzymes. • O...

Medullary osmotic gradient: countercurrent multiplier, urea recycling & vasa recta countercurrent exchange

By: HWC, Views: 8450

▪ The primary cause of the medullary osmotic gradient is the active transport of solutes. • In the ascending limb of the loop, active transport of Na+ ions drives passive reabsorption of Cl- ions. • Addition of these ions to the interstitial fluid of the medulla increases its osmolarity...

Regulation of GFR: autoregulation via tubuloglomerular feedback, neural & hormonal regulation

By: HWC, Views: 8919

• When blood pressure is above normal, rapid filtrate flow reduces ion retention so filtrate in tubule has more Na+, C1-, and water. • It is believed that vasoconstricting chemicals from the juxtaglomerular cells are released when the macula densa cells detect higher water and ion levels in ...