A crater is the top of a volcano's central vent and is funnel shaped. A caldera is a magma chamber that supplies materials to the volcano and eventually collapses when there's nothing more to supply.
Answer:
yes convection currents occur in earth's crust I hope this helps
Answer:
The correct answer is - they lack a nucleus, DNA, and organelles like the endoplasmic reticulum or mitochondria
Explanation:
Red blood cells are considered as the cells, carry oxygen with the help of hemoglobin protein present in it to the various parts of the body from the lungs and carry CO2 back to the lungs.
These cells are different from the normal cell as they do not participate in the protein synthesis due to the fact that they lack various cell organelle and cell components required. Nucleus and DNA are major components or organelle missing from these cells. In addition to these two, endoplasmic reticulum and mitochondria also missing from RBCs.