The water would freeze across the surface of the lake, blocking the dissolving of oxygen and nutrients. <span>Water is actually less dense when frozen, which is why ice cubes and ice bergs all float. This is also why you can ice skate on a lake if the ice gets thick enough on the surface. Many organisms that live in freezing lakes have special adaptations which help them survive.</span>
Answer:
In the human adult, the bone marrow produces all of the red blood cells, 60–70 percent of the white cells (i.e., the granulocytes), and all of the platelets. The lymphatic tissues, particularly the thymus, the spleen, and the lymph nodes, produce the lymphocytes (comprising 20–30 percent of the white cells).
Oil and water separate because they have different densities.
X - linked traits appear more often in males because males only have one x chromosome. One copy of an x - linked trait is all that a male would need to possess that trait. Females have two x chromosomes, so they would require 2 copies of the x - linked trait in order to possess it.