Examlex
Nonrenewable mineral resources renew over millions to billions of years.
Neurotransmitters
Chemicals that transmit signals across a synapse from one neuron to another in the brain and nervous system.
Endorphins
Natural pain-relieving and pleasure-inducing chemicals produced by the brain in response to stress, pain, or exercise, often associated with feelings of euphoria.
Selectively Permeable
Selectively permeable refers to a membrane or barrier that allows certain substances to pass through while blocking others, commonly used in biological contexts.
Negatively Charged Ions
Ions that have gained one or more electrons, resulting in a net negative charge.
Q21: Ultimately, which of the following is the
Q27: Conflicts within and between countries over scarce
Q34: China's per capita carbon dioxide emissions rate
Q39: Florida's key deer<br>A)international regulatory laws<br>B)U.S. regulatory laws<br>C)wildlife
Q74: Mountaintop removal is more damaging to the
Q84: Current models of the gasoline-electric car<br>A) may
Q85: The United States is the world's largest
Q89: Briefly explain why caution is advised in
Q98: Observe the second graph which is from
Q135: On the sources and types of air