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Biology Crossword

Across
a rapid increase or accumulation in the population of algae in freshwater or marine water systems, and is recognized by the discoloration in the water from their pigments
individual animals, plants, or single-celled life forms.
the amount of gaseous oxygen (O2) dissolved in the water
the enrichment of a water body with nutrients, usually with an excess amount of nutrients
he amount of dissolved oxygen needed (i.e. demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period
pH greater than 7
large and diverse group of bacteria
Inorganic or organic ester or salt of nitric acid, containing the (NO3-) ion
a compound of nitrogen and hydrogen with the formula NH₃
something that drains or flows off, as rain that flows off from the land in streams
a salt or ester of phosphoric acid
Down
organisms that live underwater in our streams and rivers, lack a backbone, and can be seen by the naked eye
pH of pure water
a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource
measures how acidic or basic a substance is
the cloudiness or haziness of a fluid caused by large numbers of individual particles
an organism that can survive and grow in an oxygenated environment
a measure of the warmth or coldness of an object or substance with reference to some standard value
a test for acidity or alkalinity using litmus
an abnormally low amount of oxygen in the body tissues; hypoxia
having the properties of an acid, or containing acid; having a pH below 7
potential hydrogen