The plastic bags held
more weight compared to the paper bags. The breaking points for the
plastic bags are the handles. The weak points for the paper bags are the bottom
and sides of the bag. The plastic bags held more weight and could conform to
different shapes and stretching characteristics.
Answer:
B. An idea supported by evidence.
Answer:
E. are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase.
Explanation:
Heterocysts are specialized cellular compartments found in nitrogen fixing cyanobacteria. They provide the ideal anaerobic environment for nitrogen fixation since nitrogenase enzyme cant work in presence of oxygen. Hence, in a cyanobacteria both the oxygen requiring photosynthesis process and the oxygen sensitive nitrogen fixation process takes place simultaneously.
Heterocysts have an additional cell wall made of glycolipid that provides a hydrophobic barrier to oxygen. They are involved in production of nitrogenase and other proteins that are required for nitrogen fixation. They also degrade photosystem II which is responsible for producing oxygen and produce proteins which remove any remaining oxygen.
He is WRONG
Explanation:
Any atom at the ground state has its orbital levels fill from the bottom (close to the nucleus) – up. The inner orbitals are of lower energy state and fill first because the atoms ‘likes’ to exist in the low energy and more stable state. Only when the atom is in an excited state do some of the electrons in the lower orbital levels shift to higher unfilled orbitals.