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Cell mediated immune response to a viral infection Animation

By: HWC, Views: 3897

Intracellular pathogens are the targets of cell-mediated immune response. The process begins when a virus infects a macrophage. Another macrophage engulfs the same virus or an antigen from it. In both cells, enzymes cleave the viral antigens into small bits. The fragments move to the cell sur...

Bone processes - resorption and deposition, remodeling and response to stress in adult bones

By: HWC, Views: 8084

• The process of remodeling bone tissues involves bone cells resorbing or depositing minerals into bone tissue. • During resorption, bone cells break down bone tissue and release calcium and other minerals for use by other cells in the body. • Bone cells also rebuild bone tissue by depo...

Plant Defense Mechanisms from Pathogens

By: HWC, Views: 7334

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...

Flexor reflex & Crossed extensor reflex

By: HWC, Views: 7798

• 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...

Hemodynamics Animation

By: Administrator, Views: 11621

Hemodynamics is the dynamics of blood flow. The circulatory system is controlled by homeostatic mechanisms, such as hydraulic circuits are controlled by control systems. Hemodynamic response continuously monitors and adjusts to conditions in the body and its environment.

Muscle Twitch and Muscle Tension - Motor unit size and force

By: HWC, Views: 8125

• A motor unit is a group of muscle cells controlled by a single neuron. • A stimulus of sufficient intensity will cause all the cells in the motor unit to contract. • A single contraction, caused by a single action potential, is called a muscle twitch. • Latent period: A brief per...

Inflammation Animation

By: Administrator, Views: 10863

Inflammation is caused by a number of physical reactions triggered by the immune system in response to a physical injury or an infection. Inflammation does not necessarily mean that there is an infection, but an infection can cause inflammation.

Neural Reflex Arc Animation

By: Administrator, Views: 11074

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...

Stress and Immune System Animation

By: Administrator, Views: 11084

How stress and the immune system are linked. Immune response declines with age, limiting body's ability to identify and fight foreign substances. Loss of thymus cortex leads to reduced production of T lymphocytes, including T cells, NK cells, B lymphocytes. Frequency and severity of infectio...