Obsidian is a volcanic glass. It is produced when magma from volcanoes is cooled and solidifies rapidly, before there is time for crystals to grow. It is usually black in color. It shatters like glass and makes excellent axe and arrow heads and the main mineral in it is quartz (silica).
Bedrock is the solid rock that lies underneath the soil in broken, weathered rock. It is not found beneath anything in particular, it simply lies below the loose weathered material on the surface. Bedrock may be many different types of rock that extend for kilometers down into the earth's crust.
B. Porifera. Porifera (sponges) is the only major phyla without nerves
I would say D. Osteoarthritis, presbyopia
All cells require ATP for energy.
Answer:
H2O (Water)
Explanation:
Oxygen (O2) is the final acceptor molecule after the process of aerobic respiration. Specifically, it accepts hydrogen ions at the end of the electron transport chain, the main energy-generating stage of cellular respiration.
This is why oxygen is needed to form large amounts of cellular energy, as without it, the electron transport chain cannot proceed. When oxygen accepts hydrogen ions, it forms water, a byproduct of aerobic respiration.