Light-independent reactions (dark reactions). Light reactions need light to produce organic energy molecules. Dark reactions make use of these organic energy molecules.
Capillaries are made up of very thin and flat tissues that are spread across the body. Substances are able to diffuse through the capillaries because of the presence of blood. Particularly, the red blood cells that make-up blood within the body. These cells have the ability to carry oxygen, carbon dioxide, glucose, and water to pass through the capillaries.
Theory ----> not proved yet
Law --------> a theory which is proved and universally accepted
Answer:
The correct answer is - decreased population size at all levels.
Explanation:
A decrease in the productivity of producers of an ecosystem will lead to a decrease in all other organisms of the ecosystem including top-level consumers to the bottom-level producers due to the fact that producers provide energy and food to primary consumers.
It is because they are the only organisms that convert the sunlight to usable energy and food that transfer from one trophic level to other, so if the population of producers or their productivity will decrease then there will be decreased population size at all levels.