Question

A unicellular animal P having no fixed shape ingests a food particle by forming temporary finger-like projections Q. The food particle is engulfed with a little surrounding water to form a temporary stomach R inside it. The chemicals S from surrounding cytoplasm enter into R and break down food into small and soluble molecules by chemical reactions. The digested food is absorbed directly into cytoplasm by the process T. The undigested food is thrown out of the body by the rupture of a cell organelle U in a process called V.

1. Name the unicellular animal P.
2. What are (i) Q and (ii) R?
3. Name (i) chemical S, and (ii) process T.
4. Name (i) organelle U, and (ii) process V.

Answer 1

(a) The unicellular animal P is Amoeba.

(b) 

1. Projections Q: Pseudopodia 
2. Temporary stomach R: Food vacuole.

(c)

1. Chemical S: Digestive enzymes (released by lysosomes into the food vacuole to break down complex food particles).
2. Process T: Diffusion (the movement of digested soluble nutrients from an area of higher concentration inside the vacuole to a lower concentration in the cytoplasm).

(d)

1. Organelle U: Cell membrane (the flexible outer boundary of the cell that can rupture at any point to expel waste).
2. Process V: Egestion (or exocytosis; the elimination of undigested food remnants from the cell).