Search Results

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

By: HWC, Views: 6753

• Most cells which have CD4 on their surface become Helper T cells (TN cells). • The CD4 1 cells only recognize a foreign antigen when it is presented with an antigen presenting immune cell (APC) that includes MHC-II protein. • The Helper T cell antigen receptor must match the presented...

Lymphatic System Animation

By: Administrator, Views: 446

Blood and lymph are two of the body's main fluids and are circulated through two separate but interconnected vessel systems. Blood is circulated by the action of the heart, through the circulatory system consisting largely of arteries, veins, and capillaries. Lymph does not actually circulate. ...

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

By: HWC, Views: 6995

• 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...

Role of transport in a cell

By: HWC, Views: 6805

Transport of chemicals across the plasma membrane provides the following functions: Importing molecules for the maintenance of metabolic processes. Exporting chemicals produced by the cell or waste products. Communicating with other cells, allowing for the generation and conduction of a...

What are Taste Receptors? How Does it Work? Animation

By: HWC, Views: 3496

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...

Flexor reflex & Crossed extensor reflex

By: HWC, Views: 6579

• The flexor reflex is a response to pain. This reflex is polysynaptic, ipsilateral, and intersegmental. • Pain receptors are stimulated causing increased frequency of action potentials to be generated and conducted along the sensory neuron axon. • The sensory impulses excite several ass...

Stretch reflex & Tendon reflex

By: HWC, Views: 6380

• The stretch reflex is a response to the stretching of muscles. It is monosynaptic and ipsilateral. • Stretching stimulates receptors in the muscle spindle of the agonist (stretched) muscle. • One or more action potentials are generated by the receptors and propagate along the axon of ...

Nerve Impulse Transmission Animation

By: Administrator, Views: 10002

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...

Hormonal feedback loop components

By: HWC, Views: 6790

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 b...