Explanation:
I think the answer is contraceptive pills but not sure
Arbitrary level refers to the fundamental vertical subdivision of an excavation square, implied only when easily identifiable natural strata are absent and when natural strata are more than ten centimeters thick.
Natural strata refer to a vertical subdivision of an excavation square, which is reliant on the natural breaks in the sediments in terms of grain size, color, hardness, texture, or other features.
It is important to know the difference between the arbitrary and natural levels as arbitrary levels could amalgamate artifacts from distinct natural levels, that is, of distinct geologic contexts.
The archaeologists can recover the smallest ecofacts and artifacts with the assistance of flotation, screening, and bulk matrix processing
Answer:
Roots---xylem vessel-- upper parts of plant.
Explanation:
The plant absorb water from hairs present on the roots and taken this water to the xylem vessel that is responsible for transporting water to all parts of the plant body. Water enters in the root through a process is called osmosis until it reached to the xylem vessel. Osmosis is a movement of molecules through a semi-permeable membrane into a region of higher solute concentration in order to equalize the solute concentration.
I would say energy myself, and this is because energy plays a key role in all of these. With trophic levels energy is being transferred amongst the levels. Food chain's is a map of how the energy is passed along the chain. Food web is a web of how energy is transferred, and this is why I would say energy is a keyword.
bacteria can live in hotter and colder temperatures than humans but they do best in a warm moist protein-rich environment that is pH neutral or slightly acidic