Search results for: 'small%20intestine'

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By: HWC, Views: 6761

■ 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...

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

By: HWC, Views: 6751

• 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 ...

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Predator- prey competition and symbiosis

By: HWC, Views: 6477

Predator-prey relationships occur when one species, the predator, kills and eats an organism of another species, the prey. This graph shows the cyclical nature of predator-prey relationships, in this case among populations of Canada lynx and snowshoe rabbits. If predation is without some li...

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Mycobacterium tuberculosis: Drug Resistance and Natural Selection

By: HWC, Views: 5437

The evolution of drug resistance in microorganisms, such as M. tuberculosis, that cause human diseases is of particular concern to biologists. When Mycobacterium tuberculosis infects the lungs of humans, it causes the disease tuberculosis, also called TB. Once infected, the lungs act as a new...

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Labor and Delivery - Infant Cord Apgar

By: Administrator, Views: 308

As soon as your baby is born, a delivery nurse will set one timer for one minute and another for five minutes. When each of these time periods is up, a nurse or physician will give your baby her first "tests," called Apgars. This scoring system (named after its creator, Virginia Apgar) helps t...

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Introduction to Epilepsy

By: Administrator, Views: 9763

Epilepsy is a group of neurological disorders characterized by epileptic seizures. Epileptic seizures are episodes that can vary from brief and nearly undetectable periods to long periods of vigorous shaking. These episodes can result in physical injuries, including occasionally broken bones. In ...

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Neural regulation of blood pressure - baroreceptor and chemoreceptor reflexes

By: HWC, Views: 6962

• The nervous system regulates blood pressure with two reflex arcs: baroreceptor and chemoreceptor. ■ Baroreceptors (pressure) and chemoreceptors (chemical) are located in the carotid sinus and aortic arch. • Carotid sinus reflex helps maintain normal blood pressure in brain. • Ba...

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Introduction to C-Section

By: Administrator, Views: 271

Caesarean section, also known as C-section, or caesarean delivery, is the use of surgery to deliver babies. A caesarean section is often necessary when a vaginal delivery would put the baby or mother at risk. This may include obstructed labor, twin pregnancy, high blood pressure in the mother, br...

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Energy Flow - Trophic Levels and Food

By: HWC, Views: 6211

All of these relationships between different species are founded on one thing: energy. Organisms get food in order to get energy, which is used by the organism for growth, maintaining health, and reproduction. We can classify the members of a community according to how they obtain food. Produc...

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