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In a process known as 'coral bleaching,' high water temperatures cause corals to expel the dinoflagellates that normally reside within their cells. How might coral bleaching affect coral reefs?
31. Invertebrates
Porifera and Cnideria
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Which of the following is/are characteristic of sponges?
A
They have collar cells.
B
They consist of two layers of cells with a noncellular gelatinous layer between them.
C
They have holes, or pores, in specialized cells, through which water enters.
D
None of the listed responses is correct.
E
All of the listed responses are correct.
Verified step by step guidance1
Understand that sponges are simple multicellular organisms belonging to the phylum Porifera.
Recognize that sponges have specialized cells called collar cells, or choanocytes, which help in water circulation and capturing food particles.
Identify that sponges have a body structure consisting of two layers of cells: an outer layer (pinacoderm) and an inner layer (choanoderm), with a gelatinous noncellular layer called mesohyl in between.
Acknowledge that sponges have pores, or ostia, which are openings in their body wall that allow water to enter, facilitating filter feeding.
Conclude that all the characteristics listed (collar cells, two cell layers with a gelatinous layer, and pores for water entry) are indeed features of sponges, making the statement 'All of the listed responses are correct' true.
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