Metamorphic

In fact, any rock can change to become any other type of rock. These changes usually happen very slowly. Some changes happen below Earth’s surface. These are the processes that change one rock type to another rock type.

Igneous rocks are formed from melted rock deep inside the Earth. Sedimentary rocks are formed from layers of sand, silt, dead plants, and animal skeletons. Metamorphic rocks formed from other rocks that are changed by heat and pressure underground.

Some rocks contain molecules that could have formed only in the presence of oxygen. The more of those molecules geochemists find in a rock, the more oxygen must have been in the atmosphere at the time. When they look at the oldest rocks on earth, they find no trace of oxygen in the atmosphere.

Scientists have found electricity flowing in an unexpected place — across the surfaces of rocks. Mineral coatings on rocks turn sunlight into electricity, turning on like a light switch when the sun hits them, according to a study published April 22 in the journal Proceedings of the National Academy of Sciences.

Interestingly, a study published in August in the journal Nature determined that as temperatures rise, Earth’s soil is also “breathing” more heavily. “Soils around the globe are responding to a warming climate, which in turn can convert more carbon into carbon dioxide which enters the atmosphere.

When you inhale (breathe in), air enters your lungs and oxygen from the air moves from your lungs to your blood. At the same time, carbon dioxide, a waste gas, moves from your blood to the lungs and is exhaled (breathe out). This process is called gas exchange and is essential to life.

Plants release oxygen during the day in the presence of natural light through the process of photosynthesis. While at night, the plants uptake oxygen and release carbon dioxide, which is called respiration.

Plus, they give us clean oxygen to breathe! To eat, trees go through a process called photosynthesis. To do this, their leaves pull in carbon dioxide and water through tiny pores, called stomata, and use energy absorbed from the sun to turn the CO2 and H2O into sugars.

• Oleander Nerium oleander. Key Issues: Toxic to humans and animals.
• Bonsai. Key Issues: Allergies, Skin reactions.
• Daisies, Chamomile, Chrysanthemums, and Sunflowers. Key Issues: Allergies.
• Pothos/Devil’s Ivy Epipremnum aureum.
• Orchids Orchidaceae.
• Dumb canes Dieffenbachia.
• Croton Plant Croton.
• Air Plants.