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Genetic distance between human groups

By: HWC, Views: 4573

One proposed family tree for modern humans. This family tree is based on nucleic-add hybridization studies of many genes and immuno-logical comparisons. Branch points show presumed genetic divergences. This data indicates that the greatest genetic distance separates humans native to Afri...

Nucleic acid digestion -small intestine

By: HWC, Views: 7750

Nucleic acid digestion, which takes place in the small intestine, involves: • Pancreatic nucleases. • Brush-border enzymes in the small intestine. • Nucleic acids enter the small intestine dissolved in gastric chyme. • As gastric chyme enters the duodenum of the small intestine, p...

Nucleic acid digestion - brush border enzymes, end products & transport mechanism

By: HWC, Views: 7507

• Further digestion occurs at the microvilli (brush border) of the epithelial cells of the villi in the small intestine. • Two brush border enzymes complete nucleic acid digestion: • Phosphatases, which catalyze the cleavage of a phosphate to form a nucleoside (nitrogenous base and pent...

Mendel's Principles of Inheritance (Father of Genetics)

By: HWC, Views: 7336

Gregory Johann Mendel, a monk living in the mid-1800's, is known as the "Father of Genetics" for his experiments with pea plants in the abbey garden. These experiments led him to deduce the fundamental law of genetics. Mendel was an Augustinian friar who entered, in 1843, the Abbey of St. Thom...

Major Elements in Biological Molecules: Nucleic acids

By: HWC, Views: 7629

DNA and RNA are nucleic acids (polymers of nucleotides). Two polymers with complementary nucleotide sequences can pair with each other. This pairing endows nucleic acids with the ability to store, transmit, and retrieve genetic information. Two strands of DNA pair by hydrogen bonding. A compon...

DNA Replication Factory and Protein

By: HWC, Views: 7231

DNA (deoxyribose nucleic acid) carries all the genetic information needed to re-create itself and to pass on the characteristics of the organism. The “factory” model of DNA replication hypothesizes a specific nuclear structure in which the molecular machinery for replication forks are brou...

Bond types - Atomic structure and basis of bonds

By: HWC, Views: 8095

• Chemical bonds are fundamental to the structure and function of many types of molecules, such as proteins, carbohydrates, lipids, nucleic acids, gases, salts and water. ■ These molecules are composed of atoms that are held together by three different types of bonds. • The three types ...

Properties of water -structure of water and polarity (Ionized and polar compounds)

By: HWC, Views: 7848

■ Water transports most of the molecules in the body. ■ The structure of a water molecule allows it to dissolve other molecules. ■ Shared electrons spend more time near the oxygen atom. ■ Oxygen end has a partial negative charge. ■ Hydrogen ends have a partial positive charge....

Factors that increase metabolic rate and heat production

By: HWC, Views: 7754

• All vital biochemical reactions are temperature dependent. • The overall rate at which metabolic reactions use energy is known as the metabolic rate. • Metabolic rate greatly determines body temperatures. • Temperature is maintained by balancing the loss of heat to the environment...