Question

1. define autotrophic. 6. define heterotrophic. 7. when a euglena becomes heterotrophic, how does it obtain nutrients? 8. what helps the euglena keep its shape 9. what is the eyespot used for? 10. what is the function of the nucleus? what is the function of the nucleolus? 11. what is the function of the contractile vacuole? what would happen if the cell did not have this organel 12. what do the pyrenoids do? 13. where might you find spirogyra? 14. is the spirogyra unicellular or multicellular?

Explanation:

1. Autotrophic organisms can produce their own food from inorganic substances, usually through photosynthesis.
2. Heterotrophic organisms obtain nutrients by consuming other organisms or organic matter.
3. When euglena is heterotrophic, it can engulf food particles through a process called phagocytosis.
4. The pellicle, a flexible protein - rich layer, helps euglena keep its shape.
5. The eyespot in euglena is used to detect light, which helps it move towards light sources for photosynthesis.
6. The nucleus controls the cell's activities and contains genetic material. The nucleolus is involved in ribosome synthesis.
7. The contractile vacuole in euglena pumps out excess water to maintain osmotic balance. Without it, the cell would swell and burst due to water influx.
8. Pyrenoids in euglena are involved in starch storage and photosynthesis.
9. Spirogyra can be found in freshwater environments such as ponds, lakes, and slow - moving streams.
10. Spirogyra is multicellular, consisting of long, filamentous chains of cells.

Answer:

1. Organisms that produce their own food from inorganic substances (usually via photosynthesis).
2. Organisms that obtain nutrients by consuming other organisms or organic matter.
3. By engulfing food particles through phagocytosis.
4. The pellicle.
5. To detect light.
6. Nucleus: Controls cell activities and contains genetic material. Nucleolus: Involved in ribosome synthesis.
7. Pumps out excess water to maintain osmotic balance. Without it, the cell would swell and burst.
8. Involved in starch storage and photosynthesis.
9. In freshwater environments like ponds, lakes, and slow - moving streams.
10. Multicellular.