Which statement about cell junctions is true?
A) Desmosomes and gap junctions contain keratin,whereas tight junctions contain collagen.
B) Gap junctions and tight junctions have specialized protein channels called connexins,whereas desmosomes do not.
C) Tight junctions and desmosomes have mechanical roles,whereas gap junctions facilitate communication between cells.
D) Desmosomes and gap junctions are found in epithelial tissue,whereas tight junctions are found only in nerve cells.
E) All cell junctions have different functions,though structurally they are the same.

Question

Quizplus · Accepted Answer

Tight junctions and desmosomes serve mechanical roles to provide structural support and stability to tissues, while gap junctions allow for intercellular communication by forming channels between neighboring cells. Desmosomes and gap junctions are found in a variety of tissue types, not just epithelial tissue, and all cell junctions have different structures and functions. Choice A is incorrect because desmosomes and gap junctions do not contain keratin or collagen. Choice B is also incorrect because desmosomes contain specialized proteins called cadherins, while gap junctions have specialized proteins called connexins. Choice D is incorrect because tight junctions are found in a variety of tissues, not just nerve cells. Choice E is incorrect because while cell junctions share some structural similarities, their functions are distinct.

Which Statement About Cell Junctions Is True