Page 106 - Atlas of Histology with Functional Correlations
P. 106
5. The major microtubule-forming center in the cell is the:
A. centriole.
B. mitotic spindle.
C. cilia.
D. centrosome.
E. basal body.
ANSWERS
1. Correct Answer: E. Zonula occludentes (tight junction). These structures
are located at the apical regions of the cells and play an important role in
the epithelium of the digestive organs, where they prevent the passage of
corrosive chemicals between cells.
2. Correct Answer: D. Gap junction. Of the junctional complexes, the
spotlike gap junctions exhibit tiny channels (connexons) that connect
adjacent cells and allow for communication between them. Such junctions
are vital for rapid communication in cardiac muscle cells and nerve cells.
3. Correct Answer: C. Cilia. The motor protein dynein exhibits ATPase
activity and uses the energy of ATP hydrolysis to induce cilia motility.
4. Correct Answer: A. Nuclear pores. A selective permeability membrane
with nuclear pores surrounds the nuclei of different cells. The nuclear pores
control the transport of molecules between the nucleus and cytoplasm.
5. Correct Answer: D. Centrosome. All microtubules originate from the
microtubule-organizing center in the cytoplasm called the centrosome.
ADDITIONAL HISTOLOGIC IMAGES
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