Answer: True, both of the given statements are true.
Explanation:
1. Nearly all the environment contains microorganism whether it is soil, air, water or any other surface. They have the ability of live in the extreme conditions.
There are different forms of bacteria found at different places. Some of them are thermophiles that at found in extremely hot conditions such as thermal vents.
The organism like Psychrophiles are the microorganisms that have the ability to survive at lower temperatures. Example: bacteria found in polar regions.
2. A culture can be defined as a pure culture if it has an unadulterated species of bacteria. It has no contamination and if a small inoculum from the pure sample is streaked on a plate then a pure culture of the sample is obtained.
This should be done in an aseptic condition so that the bacterial species should be free from contamination.
Over half of the people in the United States rely on groundwater for drinking water. This is true.
B. Is characterized by four different zones.
Answer: Antibiotics targets the synthesis of protein, nucleic acid, folate and cell wall.
1. Synthesis of protein; antibiotics binds to either 30s or 50s ribosomal subunits blocking the polypeptide from the exiting the tunnel thus inhibiting a full completion of protein expression or production.
2. Nucleic acid synthesis; Antibiotics also act by inhibiting genetic expression, DNA transcription and replication where DNA makes exact copies of itself, as well as RNA molecules preventing bacterial growth.
3. Cell wall synthesis; Inhibition of cell wall synthesis in microorganisms will prevent it from replication and growth.
4. Folate synthesis; Folic acid also known as vitamin B9 helps in DNA replication and cell division. Folate antagonists such as aminopterin kills bacteria by preventing folic acid production required for DNA replication.