Mark the correct statements. An incorrect marking takes away one point.

a) The perch and pikes of a lake form a population.
b) The perch and pikes of a lake belong to the same community of organisms.
c) An ecosystem can consist of a pond, its water, its fish, its rocks, its plants, etc.
d) Plants need oxygen to photosynthesize.
e) Aquatic plants release oxygen into the water, which is in turn used by fish to breathe.
f) The leaves of a plant contain chloroplasts, where the process of photosynthesis takes place.
g) The process of photosynthesis produces nutrients, such as nitrogen.
h) The process of photosynthesis produces sugar, which contains energy. It can be said that the energy from sunlight has been "converted" into sugar.
i) Herbivores are producers.
j) Plants and algae are producers.
k) During the winter, the water of a lake is layered so that the bottom of the lake contains the warmest water.

Max: 7p