A fluorescent molecule of 2000 daltons is microinjected into a single cell of an epithelial layer. When the layer is examined in a fluorescence microscope, the molecule remains confined to that cell. However, when a fluorescent molecule of 800 daltons is injected into a single cell of an epithelial layer, it quickly appears in the adjacent cells. Which of the following is responsible for the spread of the smaller molecule? 1. A) Desmosomes (maculae adherentes) 2. B) Focal contacts 3. C) Gap junctions 4. D) Intermediate junctions 5. E) Tight junctions (zonulae occludentes)

A fluorescent molecule of 2000 daltons is microinjected into a single cell of an epithelial layer. When the layer is examined in a fluorescence microscope, the molecule remains confined to that cell. However, when a fluorescent molecule of 800 daltons is injected into a single cell of an epithelial layer, it quickly appears in the adjacent cells. Which of the following is responsible for the spread of the smaller molecule? 1. A) Desmosomes (maculae adherentes) 2. B) Focal contacts 3. C) Gap junctions 4. D) Intermediate junctions 5. E) Tight junctions (zonulae occludentes)

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

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