Question

1. sponges have 3 different cell types, and one type of cell is the choanocyte. the collar is the part of the choanocyte that a. regulates the diameter of the osculum. b. filters food from the water. c. creates currents in the water. d. regulates the diameter of the ostia. 2. sponges get nutrients by all of the following ways except a. filtration. b. trapping of food items by collar cells c. active transport of nutrients. d. active predation. 3. the support structure made of collagen in some sponges is called a. spicules b. gemmules c. spongin d. ostium 4. sponges reproduce by which of the following methods? a. sperm fertilizing egg cells b. gemmules c. binary fission d. schizogomy e. all of the above f. only a and b 5. sponges create water currents to carry out cellular processes. which of the following are benefits of water currents for sponges? a. carry away digestive wastes b. bring oxygen c. bring food particles d. all of the above

Explanation:

1. Choanocyte collars have flagella that beat to create water - currents, which help in filter - feeding.
2. Sponges are sessile filter - feeders and do not engage in active predation. They use filtration, trapping by collar cells, and active transport for nutrient uptake.
3. Spongin is a collagen - like protein that forms the support structure in some sponges. Spicules are made of calcium carbonate or silica, gemmules are a form of asexual reproduction structure, and ostium is an opening.
4. Sponges can reproduce sexually (sperm fertilizing egg cells) and asexually (through gemmules). Binary fission and schizogomy are not their main modes of reproduction.
5. Water currents in sponges bring oxygen, food particles, and carry away digestive wastes.

Answer:

1. C
2. D
3. c
4. f
5. d