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Peptide Bond Formation Animation

By: HWC, Views: 3089

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...

Fermentation - When Oxygen Is Absent, Pyruvate to Lactate & Pyruvate to Ethanol

By: HWC, Views: 8854

Pyruvate is the end product of glycolysis. If oxygen is present, pyruvate enters the mitochondrion where further energy yielding reactions of the Krebs cycle will take place. However, if oxygen is not present, pyruvate will enter a pathway called fermentation. This pathway regenerates NAD+ fro...

Hormonal feedback loop components & Glucagon (glycogenolysis and gluconeogenesis)

By: HWC, Views: 9162

The endocrine system maintains many body conditions within normal limits with feedback loops. Each endocrine feedback loop maintains homeostasis using the following components: • Stimulus - a change in a body condition. • Production cell - an endocrine cell that produces a hormone after ...

Electromagnetic Spectrum, Chlorophyll and Pigment & Light

By: HWC, Views: 9095

The sun gives off radiation that is called the electromagnetic spectrum. This is energy that travels as wavelengths and includes radio waves, X-rays and ultraviolet light. A portion of this radiation is known as visible light, and is the type of radiation that plants use to manufacture sugars. ...

Acid-base imbalances - metabolic acidosis and alkalosis

By: HWC, Views: 9431

• Metabolic acidosis typically results from very low HCO3- ion blood concentrations. • Metabolic alkalosis typically results from very high HCO3- ion blood concentrations.

Definition of heart rate

By: HWC, Views: 9491

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...

Griffith's experiments

By: HWC, Views: 6507

In the late 1920s, Fred Griffith was attempting to develop a vaccine against a bacterium that causes pneumonia. To find out why two strains of the bacteria differed in their deadliness, he injected mice with four different mixtures. Mice injected with R cells remained healthy. When Griffith ex...

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

By: HWC, Views: 10485

• 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 ...

Mechanisms of capillary exchange

By: HWC, Views: 9465

■ 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...