They will avoid areas where DO levels are below 3 mg/L, but generally do not begin to suffer fatalities due to oxygen depletion until levels fall below 2 mg/L 22. The mean DO levels should remain near 5.5 mg/L for optimum growth and survival Â¹Â².n a stable body of water with no stratification, dissolved oxygen will remain at 100% air saturation. 100% air saturation means that the water is holding as many dissolved gas molecules as it can in equilibrium.
Lesson Summary. 1  Most protist diseases in humans are caused by protozoa. 2  Protozoa make humans sick when they become human parasites. 3  Trypanosoma protozoa cause Chagas disease and sleeping sickness. 4  Giardia protozoa cause giardiasis, and Plasmodium protozoa cause malaria.esson Summary. 1  Most protist diseases in humans are caused by protozoa. 2  Protozoa make humans sick when they become human parasites. 3  Trypanosoma protozoa cause Chagas disease and sleeping sickness. 4  Giardia protozoa cause giardiasis, and Plasmodium protozoa cause malaria.
1. Single gene disorders: disorders caused by defects in one particular gene, often with simple and predictable inheritance patterns. 1  Dominant diseases: single gene disorders that occur when an individual has one altered copy of the relevant gene and one healthy copy.2  For example, Huntingtonâs disease.. Multifactorial disorders (complex diseases): disorders caused by changes in multiple genes, often in a complex interaction with environmental and lifestyle factors such as diet or cigarette smoke.