Search results for: 'Helper T cell receptors'

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By: Administrator, Views: 11118

How nerves transmit impulses. Stimulation of a nerve occurs at a receptor. Sensory receptors Specialized to specific types of stimulation such as heat, cold, light, pressure, or pain. React by initiating a chemical change or impulse. All-or-none principle Means that no transmission occ...

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What are Taste Receptors? How Does it Work? Animation

By: HWC, Views: 4615

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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Introduction to Insulin

By: Administrator, Views: 11846

The islets of Langerhans are composed of three major types of cells: Alpha cells secrete glucagon, elevating blood sugar. Beta cells secrete insulin, maintaining normal blood sugar. Delta cells secrete somatostatin, which suppresses release of glucagon and insulin. Hyposecretion or inadequa...

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Male Reproductive System - The gonadotropin releasing hormone

By: HWC, Views: 8484

• Hormonal mechanisms that influence male reproductive function involve endocrine tissues contained in the: • Hypothalamus of the brain. • Anterior pituitary. • Testes. • In the hypothalamus, certain neurosecretory cells secrete gonadotropin- releasing hormone (GnRH). • GnRH ...

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Component of feedback systems & Communication and regulation of body systems

By: HWC, Views: 7867

• 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 ...

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Cellular defenses (natural killer cells, phagocyte types & process of phagocytosis)

By: HWC, Views: 7478

• Lymphocytes that rapidly defend against abnormal (cancer) or virus-infected cells. • Found in blood, spleen, lymph nodes, and red bone marrow. • Lack receptors for binding with specific antigens. • Act upon cells displaying abnormal MHC antigens. • NK cells destroy cells in ...

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Neurotransmission at chemical synapses & Excitory and inhibitory potentials

By: HWC, Views: 7670

• A series of events occur at chemical synapses in order to communicate with the adjacent cell. • The action potential arrives at the presynaptic membrane. • The depolarization phase of the action potential opens voltage gated Ca+ channels. • increased inflow of Ca+' into the cyto...

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Osmosis - Isotonic, Hypotonic, and Hypertonic Solutions

By: HWC, Views: 7846

Isotonic: Equal Water moves in and out of the cell at an equal rate. The cell remains unchanged. Hypotonic: "hypo" hippo Water moves into the cell, making it swell and get fat (like a hippo). Eventually the cell can rupture and burst (aka lyse). Hypertonic: "like a raisin" Water leaves...

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Neural Reflex Arc Animation

By: Administrator, Views: 10946

A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons without the delay of routing signals through the bra...

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