Ice float because it's a solid. A way to explain it to a child would be by saying it has bubbles in it so that's why it floats.
<span>E. Stimulation of T-cell by APC</span>
The initial exposure of the body to an infectious agent e.g. through a vaccine, triggers an immune response most of which rapidly diminishes after the vaccination. However some cells of the immune system called lymphocytes remain with a memory of that pathogen.As a result, if the same pathogen infects a vaccinated person, the memory cells remember and recognize it and rapidly spring into action triggering a much more rapid response specific to that pathogen than the initial exposure, effectively dealing and neutralizing the pathogen.
Most important and abundant one are the phospholipids - amphiphatic molecules with an hydrophilic head and a hydrophobic hydrocarbon tails. They compose the membrane bilayer. Also important are the membrane proteins, which can be periheric and internal and can serve as channels, receptors, pumps etc.
Depending on the cell type the membrane can also contain cholesterol (in animal cells, enhances the membrane stability) or hopanes(in prokaryotes, same function as cholesterol) or ether-phospholipids with branched hydroharbon tails(in archaea, make the membranes more stable and resistant to severe conditions, as archaeas are extremophiles)
Explanation:
Enzymes. Most enzymes are proteins and therefore their function is specific to their structure. ... The enzyme binds with the appropriate substrate only in the correct alignment and orientation to connect the molecules. The resulting enzyme-substrate complex enables the reaction to occur.
Answer:
False.
Explanation:
Sterilization technique is a method in which low temperatures is used for controlling of microorganisms growth which causes infection in food materials, while in microbicidal method, compounds are used to decrease the growth of harmful microorganisms in a substances which causes infection. Wood tar is the example of microbicidal compound.
