Search results for: 'Enzyme concentration'

Watch Later 1:43

By: HWC, Views: 7012

This apparatus of beakers A and funnels simulates the flow of a sucrose solution in the phloem of a plant. The funnels and connecting tube represent a sieve tube of the phloem. Differentially permeable membranes cap the funnels at the source and sink ends, allowing water, but not sucrose, to cros...

Watch Later 2:38

Hormonal feedback loop components & Glucagon (glycogenolysis and gluconeogenesis)

By: HWC, Views: 7544

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 after ...

Watch Later 2:11

Hemoglobin's affinity with oxygen - carbon dioxide, temperature and bisphosphoglycerate (BPG)

By: HWC, Views: 7833

• The carbon dioxide gas is temporarily converted to carbonic acid in red blood cells by the enzyme carbonic anhydrase, and then further converted to hydrogen and bicarbonate ions. • The result of increased carbon dioxide is decreased pH causing the Bohr effect. • Elevated carbon dioxid...

Watch Later 1:33

Parathyroid hormone (bone resorption) & Calcitonin (bone deposition)

By: HWC, Views: 7709

• Cellular needs for calcium may cause blood calcium concentrations to decline below the normal range. • This decrease stimulates cells in the parathyroid gland to secrete parathyroid hormone. • Binding of parathyroid hormone to osteoclasts in bone tissue promotes bone resorption and th...

Watch Later 2:54

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

By: HWC, Views: 7901

▪ 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. ...

Watch Later 3:10

Role of the respiratory system - effect of altered ventilation rates

By: HWC, Views: 7600

• Dissociation of the chemical substances in the body fluids can result in the production of free hydrogen ions. • The pH scale is used to measure the concentration of hydrogen ions in solution. • Normal blood pH values vary around 7.4. • When hydrogen ion concentration increases, t...

Watch Later 4:06

Chloroplast Structure & Light Dependent Reactions (Photosystem 1 and 2 Cyclic Electron Flow)

By: HWC, Views: 7325

The leaf is the principle photosynthetic organ of the plant. This is a cross section of a leaf. The rectangular-shaped cells are part of the photosynthetic tissue called the palisade mesophyll. Each photosynthetic cell can contain several hundred organelles known as chloroplasts. The chlorop...

Watch Later 1:19

Medullary osmotic gradient - influencing factors

By: HWC, Views: 8076

▪ 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...

Watch Later 1:26

Insulin (glucose uptake by body cells), glycogenesis and lipogenesis

By: HWC, Views: 7852

Insulin is the regulator that allows the sugar from the foods we eat (be it a piece of cake or a stick of celery) to enter our tissues and become part of the metabolic process. Insulin is made by the Islets of Langerhans, which are found in the pancreas of every person. As we previously mentio...

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