Final answer:
The food chain order starting with grass (producer), followed by an insect (primary consumer), then a warthog (secondary consumer), and ending with a lion (tertiary consumer) depicts the energy flow in an ecosystem.
Step-by-step explanation:
To construct a food chain starting with the producer from the following organisms: grass, lion, insect, warthog; you should begin with grass, as it is the producer. In an ecosystem, producers like grass use photosynthesis to create their own food and are the foundational level of the food chain. Next in line are the herbivores, or primary consumers, which would be the insect that eats the grass. Following the insect, the warthog, which is also a herbivore, would eat the grass and possibly insects, placing it as the secondary consumer. Lastly, the lion, being a carnivore and apex predator, preys upon the warthog, making it the tertiary consumer. Thus, the food chain would look like this:
Grass (Producer)Insect (Primary Consumer)Warthog (Secondary Consumer)Lion (Tertiary Consumer)
This sequence reflects the flow of energy and nutrients in an ecosystem from producers to higher-level consumers.