Exam 16: Cell Walls, the Extracellular Matrix, and Cell Interactions

Describe the process of adhesion between leucocytes and endothelial cells that allows leucocytes to leave the circulation and enter an inflamed tissue.

Desmosomes are held together by the adhesion of the two desmosomal cadherins:

Which proteins attach integrins to actin filaments at focal adhesions?

Adhesion of plant cells is mediated by a pectin-rich region of the cell wall called the

Which statement about collagen is false?

The smallest amino acid is

Why does a mutation in a gene for the gap junction protein not affect gap junction function in all tissues that have gap junctions?

The major function of adhesion proteins such as fibronectin is to

The major family of calcium-mediated cell-surface adhesion molecules is

In vivo, epithelial cells exhibit basolateral and apical surfaces. The tight junctional complex separates these two distinct cell surfaces from each other and joins the cells into an epithelial cell layer. In vivo cells showing such properties are resistant to ion flow across the cell layer. In vitro, many cultured epithelial cell systems show high electrical resistance but fail to exhibit a polarized distribution of proteins and lipids between the apical and basolateral surfaces. Present a working hypothesis to explain this observation.

A junctional complex consists of a tight junction associated with both adherens junctions and

What are the three cell-to-cell junctions found in the junctional complex between two intestinal epithelial cells?

Adherens junctions and desmosomes may be distinguished from each other on the basis of

Which of the following molecules mediate the association of actin filaments with the cadherins in an adherens junction?

Integrins bind to

Which statement about integrins is false?

Which of the following can pass through gap junctions?

Which of the following antibiotics inhibits the synthesis of bacterial cell walls?

Integrins link extracellular matrix proteins, either directly or indirectly, to all of the following intracellular proteins except

Cell adhesion mediated by selectins, integrins, and most cadherins requires divalent cations.