Rigid skeletons are formed from materials including chitin (in arthropods), calcium compounds such as calcium carbonate (in stony corals and mollusks) and silicate (for diatoms and radiolarians).
Answer:
Explanation:
1st question is humans eat other organisms to get nutrients they need to survive.
2nd one is Eukaryota domain
Treatment
Meningitis is an infection of the membranes, meninges that surrounds and protects the central nervous system (the brain and spinal cord). Bacterial meningitis must be treated immediately with intravenous antibiotics and sometimes corticosteroids and, of course, the antibiotic depends on the type of bacteria causing the infection.
Prevention
First of all, to prevent the spread of bacterial meningitis it is important to practice good hygiene, such as frequent handwashing. Since the factors that increase the risk include spending time in communities (school, campus or college) because it spreads easily, children should be aware and vaccinated. As several types of bacteria can cause bacterial meningitis, a range of vaccines is wide (e.g. meningococcal vaccine, Hib vaccine).
