Question

Euglena is microbial eukaryote that has chloroplasts and can thus perform phtosynthesis. When deprived of light and treated with specific chemicals in lab, the chloroplasts are completely destroyed. Based on the information above, if we re-expose Euglena to light what do you predict will happen?

Answer 1

Re-exposure of Euglena to light after chloroplast destruction will not restore photosynthesis; instead, Euglena will continue to survive as a heterotroph until it possibly re-acquires chloroplasts through secondary endosymbiosis or other means.

Step-by-step explanation:

When Euglena, a microbial eukaryote, is deprived of light and its chloroplasts are destroyed, reintroducing it to light will not prompt the immediate restoration of photosynthesis. Having lost their chloroplasts, they cannot simply regrow them upon exposure to light. Instead, Euglena will rely on its ability to behave as a heterotroph, acquiring nutrients and energy by ingesting or absorbing organic matter from its environment. Euglena is known as a mixotroph, which means it can switch between autotrophic (photosynthesizing) and heterotrophic lifestyles, depending on the available resources. Euglena stores energy in a glucose polymer different from typical starch, and this storage, along with other nutrients absorbed from the environment, can support them when photosynthetic capability is compromised.

Answer 2

Euglena have diversed nutritional requirements. They are autotrophic when kept in light and heterotrophic when deprived of light.

The Euglena contains chloroplast in it to perform photosynthesis in the presence of light.

When the Euglena is kept in the dark it starts deriving energy from the organic matter around it and shows heterotrophic mode of nutrition.

When light will be provided to Euglena it will start resynthesizes its photosynthetic pigment and it will start perform photosynthesis.