What causes bacteria to die in an extremely salty environment is dehydration due to the loss of osmotic balance in their cells.
Water molecules would normally move from the region of high water potential or low solute concentration to the region of low water potential or high solute concentration through a biologically permeable membrane.
<em>An extremely salty environment would be hypertonic to the cells of bacteria and the cell walls of bacteria act as biologically permeable membranes. Hence, the bacteria cells lose water due to the osmotic movement of water from their cells to the surrounding salty environment. </em>
Your answer is probably A). If you find a fossil of an armored fish in layer A, and you find a fossil of a trilobite in layer B (five layers deeper), then you can safely assume that the trilobite is older than the armored fish.
Chemical digestion involves breaking down the nutrients into smaller cells Physical digestion is using physical movements such as chewing and swallowing
