Concept explainers
a.
To determine: The location and function of choanocytes.
Introduction: Choanocytes are present in sponges. They have flagella and fringe of protoplasm is present at the base of flagella. They are also known as “collar cells”. They make up a layer called choanoderm in sponges.
a.
Explanation of Solution
Location: Choanocytes are usually flagellated. These flagellated choanocytes line the spongocoel. Spongocoel is the large cavity present in the center of sponges.
Function: The functions of choanocytes are as follows:
- They create water current enabling the flow of water through the sponge.
- They trap bacteria and engulf food particles by the process of phagocytosis.
b.
To determine: The location and function of amoebocytes.
Introduction: They are present in sponges and also in many other groups of invertebrates. They are capable of amoeboid movement due to presence of pseudopodia.
b.
Explanation of Solution
Location: Amoebocytes are present in the mesohyl region. Mesohyl is the gelatinous layer that separates the two body layers of sponges.
Function: The functions of amoebocytes are as follows:
- They move through the mesohyl and take up food materials from choanocytes and surrounding water medium.
- Digest food material and carry the nutrients to other cells through their amoeboid movement.
- They manufacture the tough skeletal fibres inside the mesohyl.
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Chapter 33 Solutions
Study Guide for Campbell Biology
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