When the temperature reaches 0˚C (32˚F), the top layer of the lake freezes and turns into ice. In solid form, water molecules are less dense and thus ice floats on the top of the lake.
This solid barrier prevents any wind-induced mixing as well as protects the relatively warm water underneath. Furthermore, light is also blocked so that photosynthesis is inhibited during this period. As the lake water is separated from the atmosphere, no direct oxygen diffusion occurs.
All these factors together causes a more even distribution of nutrients and gases in a lake in winter.
<span>Shot in the head, the victim died instantly because the bullet entered the MEDULLA, the portion of the hindbrain that regulates breathing</span>
A. direct B. indirect C. direct D. indirect
Competition occurs by direct and indirect means. Organisms interact directly by fighting (aggression) for scarce resources. Two eagles fighting over the salmon carcass and two colonies of ant clashing over a wasp are samples of aggression (direct competition)
Indirect competition happens when there is a common or limited <span>supply of at least one resource (food, water, and territory). </span>Use of this resource lessens and later depletes the amount available to others, or they compete for space.<span> Gray foxes preying on penguins and squirrels relying on nuts for food are samples of indirect competition.</span>
Because both eat primary consumers.
Answer:
are hydrogen, oxygen, nitrogen, and carbon,
Explanation:
which together make up over 99% of the mass of most cells. They are the lightest elements capable of forming one, two, three, and four bonds, respectively