Question

6.1 what is phagocytosis? what function does it serve?
6.2 relative to other unicellular protists, how would you characterize the size of amoebas?
6.3 why would excess water tend to accumulate in amoebas?
6.4 do amoebas have a rigid cell wall? how can you tell?
6.5 do amoebas have a “permanent” anterior end like many other motile protists? explain.

Explanation:

6.1 Phagocytosis is a process by which cells engulf and digest particles. It serves functions like immune - defense by removing pathogens and nutrient - acquisition by ingesting food particles.
6.2 Amoebas are generally larger in size compared to many other unicellular protists. They can change shape and extend pseudopodia, which contributes to their relatively larger appearance.
6.3 Excess water accumulates in amoebas because they live in hypotonic environments. Water moves into the cell by osmosis as the solute concentration inside the cell is higher than in the surrounding medium.
6.4 Amoebas do not have a rigid cell wall. This can be seen from their ability to change shape freely and extend pseudopodia. A rigid cell wall would restrict such shape - changing movements.
6.5 Amoebas do not have a "permanent" anterior end. They move by extending pseudopodia in different directions as needed for locomotion and feeding, so there is no fixed anterior end.

Answer:

6.1 Phagocytosis is the process of cell - particle engulfment and digestion. It helps in immune - defense and nutrient - acquisition.
6.2 Amoebas are relatively large among unicellular protists.
6.3 Due to osmosis in hypotonic environments.
6.4 No, because of their shape - changing ability.
6.5 No, as they move by extending pseudopodia in different directions.