1. what is the usual cause of a harmful increase in the nutrients in a freshwater lake?
a. global warming
b. runoff of fertilizers and sewage
c. loss of biodiversity
d. seasonal variations in rainfall.

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.

linnaeus is the father of taxonomy, which is the system of classifying and naming organisms. one of his contributions was the development of a hierarchical system of classification of nature. today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.

answer; (b) clear with a slight blue tint;