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Results for: 'pressure flow model of phloem translocation'

Heart Chambers

By: Administrator, Views: 9730

Circulation of blood through the chambers of the heart Septum divides heart into the right and left heart. Each side contains an upper and lower chamber: Atria, or upper chambers, receive blood. Ventricles, or lower chambers, pump blood. Valves control intake and outflow of blood in chamber...

TRH/TSH/Thyroid hormone

By: HWC, Views: 6228

Thyroid hormone production • A decline in metabolic rate caused by increased metabolic need or physical exertion stimulates the production of thyrotropin hormone releasing (TRH) hormone from the cells of the hypothalamus. • Thyrotropin hormone releasing hormone targets the thyrotrophic ce...

Renin/Angiotensin (water gain from urine & Na ion and water reabsorption)

By: HWC, Views: 6565

• Sensing declining blood pressure or blood volume, juxtaglomerular cells of the nephron release renin, an enzyme that promotes the formation of angiotensin II. • Angiotensin II targets smooth muscle cells in blood vessels that provide blood to the nephron. • Angiotensin II causes thes...

Red Blood Cells - Erythropoietin (EPO)

By: HWC, Views: 6682

• 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 aft...

Atrial natriuretic peptide (vasodilation) & Aldosterone

By: HWC, Views: 6345

• Certain situations will cause the body's stress level to rise. • increased blood pressure will stretch the atria of the heart, stimulating the secretion of atria natriuretic peptide (MP). • ANP causes muscle cells in blood vessels to relax. • Blood pressure is lowered as a result ...

Double Vacuum Process (Illustration No Audio)

By: HWC, Views: 5894

In this so-called low-pressure process, the wood is first subjected to a short and relatively weak initial vacuum, after which the treatment vessel is flooded with preservative solution and reduced to normal pressure The double vacuum container is loaded with timber. A partial vacuum is draw...

Plant Defense Mechanisms from Pathogens

By: HWC, Views: 6106

Plants and pathogens have coevolved such that pathogens can recognize plants by the sugars, or other molecules, they produce. Plants, in turn, can recognize pathogens by the molecules they produce. The ability to recognize pathogens allows plants to activate defense systems that can prevent wides...

Gas exchange - partial pressure, locations, external and internal respiration

By: HWC, Views: 6831

▪ In a mixture, each individual gas exerts a pressure that is proportional to the concentration of that gas within the mixture. • This part of the total pressure is called a "partial pressure". • A gas moves along the part of the pressure gradient determined by its own concentration. ...

What are Taste Receptors? How Does it Work? Animation

By: HWC, Views: 3502

Do you ever wonder how you can taste the foods you eat? It all starts with taste receptors in your muscular tongue. Taste receptor neurons are found in your taste buds but you are not looking at the taste buds. The raised bumps on the surface of the tongue that you see are specialized epith...

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