Question

6. Define each of the four types of feeders identified in this lab. 7. Explain how they have adapted to feeding in their environment. 8. Why are stationary organisms usually filter-feeders? 9. Early scientists classified sponges as plants. Based on your observations of the sponge's feeding system, why do you think scientists now classify sponges as animals? Why can they be classified as animals if they don't move? 10. Jellyfish cannot swim rapidly, yet they are efficient predators. How are they adapted to predatory life despite their lack of speed? 11. Why are scavengers usually found in the lower part of the coral reef habitat?

Answer 1

Question 6/7) I require the lab that this is in reference to.

8) Food for stationary organisms comes to them via tidal currents. Tidal currents carry food in the form of bacteria and algae. Filter feeders are able to efficiently filter this water and obtain nutritious particles from it. Most predators are not able to feed on these filter feeds. Thus these organisms do not require motion and can remain stationary.

9) Sponges were originally classified as plants because they are sessile and lack true tissue development. Based on their embryo feeding habits, sponges are now classified as animals. Plants are autotrophic (i.e.. They make their own food via the process of photosynthesis) however sponges are heterotrophic. This means that they rely on other organisms for food just like animals. Sponges are also multicellular and have multiple tissue layers as well as systems which provides evidence of them being classified as animals.

10) Jellyfish are efficient predators due to the development of stinging cells called Cnidocytes. Each Cnidocytes contain a nematocyst which is a capsule. When this brushes against a prey, it uncoils and anchors the stinging thread into the prey. This stinging thread may cause paralysis or death of the prey.
In this manner, Jellyfish act as efficient predators.

11) Scavengers feed on dead organisms and it causes decay. When organisms die, they start drifting downwards. Scavengers are present at the bottom of the ocean where these dead organisms end up. This gives Scavengers the optimum position to obtain food.