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Chemical Buffers - protein buffer, phosphate buffer system and bicarbonate buffer system

By: HWC, Views: 8015

• There are a variety of chemicals in body fluids that prevent the fluids from undergoing large changes in. • These chemicals buffer or regulate fluctuations in H+ concentration. • Chemical buffers: • Bind to H+ ions when there are too many in a solution so pH remains normal. •...

Cytotoxic T cell receptors, activation, proliferation, differentiation & action

By: HWC, Views: 8095

• Most cells which have CD8 on their surface become cytotoxic T cells (Tc cells). • CD8 T cells recognize a foreign antigen when it is presented in conjunction with the protein, MHC-I. • Nearly all nucleated cells in the body express MHC-I molecules. • T cells that recognize self-pe...

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

By: HWC, Views: 7701

• 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...

Forming urine ( influencing factors), Forming dilute urine & Forming concentrated urine

By: HWC, Views: 8262

• The amount of urine produced by the nephron depends on : • Body fluid volume. • Body fluid composition. • Dilute urine is formed when the body is normally hydrated. • The medullary osmotic gradient determines the osmolarity of the filtrate. • Filtrate osmolarity increase...

Component of feedback systems & Communication and regulation of body systems

By: HWC, Views: 7916

• Primary responsibility for communication and regulation in the body is shared by the nervous and endocrine systems. • The two systems work alone or together in specialized physiological processes called feedback systems to maintain homeostasis. • Feedback systems - or loops - are ...

Body plan of euglena Animation

By: HWC, Views: 2102

Euglenoids are single-celled organisms that live in lakes and ponds. A contractile vacuole pumps out the water that diffuses into the cell from its hypotonic surroundings. The body is covered by a translucent pellicle composed of flexible strips of a protein-rich material. Light passe...

Interpreting a cladogram Animation

By: HWC, Views: 1431

Using a cladogram to determine relative relatedness and whether the lungfish is more closely related to a human or to a trout. To determine the relative relatedness, we begin by tracing the branches from the human and the lungfish to the point where they meet. We'll call this node 1. Now...

Condensation and Hydrolysis Animation

By: HWC, Views: 1615

A condensation reaction joins two molecules together to form one larger molecule. An enzyme removes a hydroxyl group from one molecule and a hydrogen atom from another, then speeds the formation of a bond between the two molecules at their exposed sites. Typically the discarded atoms join t...

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

By: HWC, Views: 7916

• 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 ...