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Neural regulation of blood pressure - baroreceptor and chemoreceptor reflexes

By: HWC, Views: 8008

• 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...

Glomerular filtrate rate: pressures that affect GFR, NFP & GFR and blood composition

By: HWC, Views: 8219

• The glomerular filtration rate is the amount of filtrate formed per minute within the renal corpuscle. • Once the filtrate is formed it moves down the tubule. • The production and movement of filtrate depends on three pressures: I. Glomerular blood hydrostatic pressure (GBHP) is ...

What is an ecosystem?

By: HWC, Views: 7588

An ecosystem is a community of organisms and their environment. The community forms the living component of the ecosystem. These are called the 'biotic' factors, which means all of the living things in the ecosystem. The environment forms the nonliving component of the ecosystem, such as ...

Role of the respiratory system - effect of altered ventilation rates

By: HWC, Views: 8272

• The respiratory system regulates blood pH by controlling the amount of carbon dioxide removed from the blood. • Near systemic cells, carbon dioxide forms bicarbonate ions in the blood. H+ ions are also released, thereby decreasing blood pH. • At the alveolar capillaries, bicarbonate io...

Griffith's experiments

By: HWC, Views: 4884

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...

Genetics of Cancer

By: Administrator, Views: 10886

Cancer refers to any malignant tumor. Incidence of cancer is five times higher than 100 years ago. Strikes 1 of every 3 Americans. Has become one of the more treatable of the major diseases in the U.S. Highly advanced surgical techniques Chemotherapy and radiation therapy Immunotherapy and ...

Stress and Immune System Animation

By: Administrator, Views: 10947

How stress and the immune system are linked. Immune response declines with age, limiting body's ability to identify and fight foreign substances. Loss of thymus cortex leads to reduced production of T lymphocytes, including T cells, NK cells, B lymphocytes. Frequency and severity of infectio...

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

By: HWC, Views: 7877

• 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 ...

Depolarization of the SA node, Action potentials of the myocardium & ANS effects

By: HWC, Views: 7638

• A typical contractile cell in the myocardium has a resting membrane potential. • The resting membrane potential of cells in the SA node is not fixed, and is known as the pacemaker potential. • The action potential of a healthy SA nodal cell has three parts: • Pacemaker potential: ...