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Hierarchical Sequencing Method - Sequence Tagged Sites

By: HWC, Views: 6991

In the hierarchical sequencing method, researchers begin by collecting cells. In humans, each cell contains 23 pairs of chromo-somes. Here we specifically track the DNA from just one of the 23 pairs. Chromosomes have a series of unique DNA sequences, called sequence-tagged sites (STSs), that a...

Energy sources - types

By: HWC, Views: 7929

• The amount of ATP stored in a skeletal muscle cell can only provide muscular activity for two to three seconds. • Muscle cells must be able to generate additional molecules of ATP to continue contracting. • Muscle cells can generate ATP from several processes: • Phosphogen syste...

Factors that affect conduction rates (myelination, axon diameter & temperature)

By: HWC, Views: 7880

• Several factors determine the rate of conduction of action potentials: • Myelination • Axon diameter • Temperature • The step-by-step depolarization of an axon is called continuous conduction and occurs along unmyelinated axons. • Neurons in the PNS have many axons that ...

Hormones and the menstrual cycle Animation

By: HWC, Views: 4682

Feedback loops to the hypothalamus and pituitary gland from the ovaries during the menstrual cycle Animation for a step-by-step explanation. Production of a releasing hormone (GnRH) by the hypothalamus prods the pituitary's anterior lobe to release FSH and LH. In the ovary, FSH and LH stimula...

Major Elements in Biological Molecules: Lipids

By: HWC, Views: 7072

A triglyceride (also called triacylglycerol) is composed of three fatty acid molecules and one glycerol molecule. The fatty acids attach to the glycerol molecule by a covalent ester bond. The long hydrocarbon chain of each fatty acid makes the triglyceride molecule nonpolar and hydrophobic. Pa...

Enzyme structure - Properties of enzymes

By: HWC, Views: 7699

■ Enzymes are proteins that catalyze reactions. ■ Some enzymes have two parts: a protein or apoenzyme and a non-protein or cofactor. ■ Cofactor can be a metal ion or another organic molecule called a coenzyme. ■ Coenzymes often come from vitamins. ■ Cofactors affect the shape of...

Medullary osmotic gradient - influencing factors

By: HWC, Views: 8080

▪ Maintenance of fluid volume and composition, despite changes in water input and output, is crucial to a healthy life. ▪ Regulation of blood's osmolarity, or solute concentration, is a function of the nephron. • Normal osmolarity is maintained by the ability of the nephron to alter uri...

Types of antimicrobial substances (interferons & complement protein)

By: HWC, Views: 7775

• Found in blood and interstitial fluids. • Discourage microbial growth. • Include interferon and complement proteins. • Produced and released by virus-infected lymphocytes. • Enter new cells and inhibit viral replication. • Act against a large variety of viruses (non-speci...

Electrocardiogram Examination

By: Administrator, Views: 10590

An electrocardiogram (ECG or EKG) is a test that checks how your heart is functioning by measuring the electrical activity of the heart. With each heartbeat, an electrical impulse (or wave) travels through your heart. This wave causes the muscle to squeeze and pump blood from the heart. Sinoat...