View the animation to see how one type of immune cell—the helper T cell—interprets a message presented at the surface of the cell membrane. The message is an antigen, a protein fragment taken from an invading microbe. A series of events unfolds that results in the production of many clones of...
A cancer tumor forms in a bed of healthy cells. The animation goes on to show how the tumor recruits blood vessels and how metastasis occurs.
Genes associated with autism affect the structure and function of neuronal synapses.
Demonstrates how changes in the amount of fat tissue lead to changes in leptin levels and thus changes in appetite.
Long-term memory requires the activation of CREB, turning on specific genes that support new synaptic growth.
Short-term memory relies on serotonin activating a protein kinase to modify existing synaptic strength.
Early LTP (short-term memory) depends on a calcium-dependent protein kinase to strengthen an existing synapse.
Late LTP (long-term memory) involves dopamine activation of CREB to support new synaptic growth.
Electrical and chemical signals are used by neurons to communicate with one another at contact points called synapses.
Multiple cone snail toxins attack different molecules of the nervous system and cause paralysis.
The PPAR-gamma receptor activates certain genes in a fat cell, resulting in the storage of fat and changes in hormone levels.
Prialt, a drug derived from cone snail venom, paralyzes fish by blocking calcium channels at a motor synapse.
Varying concentrations of a signaling molecule activate different transcription factors and determine cell fate.
A single transcription factor controls this operon, which contains five genes necessary to produce bioluminescence.
The zebrafish heart is similar to the human heart in many respects. But unlike the human heart, the fish heart closes wounds rapidly and then regenerates to nearly full function. Fibroblast growth factor (FGF) is an important molecule in the regeneration process.