List, in order, the events in visual perception that must occur for a person to see an object:
1. Potassium channels opens, allowing potassium ions to move out.
2. Some sodium channels open in the dendrite.
3. All ion channels close and the Na+/K+ exchange pump starts working.
4. Sodium ions diffuse toward a node of Ranvier.
5. Lights hit the retina.
6. The threshold level is reached.
7. Many sodium channels open in the axon membrane, allowing sodium ions to move in.

The terrestrial planets are characterized by having a a.) silicate core b.) iron-rich silicate core c.) iron-rich metallic core d.) none of these

Which of the following is the source of energy for photosynthesis? a.) glucose b.) chlorophyll c.) carbon dioxide d.) sunlight

(select all the correct choose each statement that is scientific. - the opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on earth. - the universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago. - ocean tides are caused by the uneven gravitational pulls of the moon and sun on different parts of earth. - human life is more valuable than other forms of life on earth because humans are more intelligent than other organisms.