Exam 7: Interactions Between Cells and Their Environment

What is the function of most IgSFs?

Attachment of an integrin to its ligand can induce which of the following responses within a cell?

Which tissues below are typically derived from the epithelium on the dorsal surface of a mammalian embryo once some of these cells begin expressing N-cadherins and stop expressing E-cadherins?

What changes in the central region of the dorsal surface of the single-celled epithelial layer of a chick embryo lead to the formation of the primitive nervous system? (Select all correct responses)

Which disease is an inherited blistering disease that can occur in patients with genetic alterations in any one of a number of hemidesmosomal proteins, including the $\alpha$ ₆ or $\beta$ ₄ integrin subunit, collagen VII or laminin-5?

What would be the effect on primordial germ cells when an embryo is exposed to laminin-specific neutralizing antibodies?

Type II collagen gene mutations alter the properties of cartilage tissue and are known to cause _______.

Animals lacking the claudin-1 gene suffered from ___________.

The basement membrane of the__________ may thicken abnormally in long-term diabetics causing kidney failure.

What can be described as a tightly adherent, polarized cell layer?

The degradation of the extracellular matrix, along with cell surface proteins, is accomplished mostly by a _____-containing enzyme family called MMPs.

Cells were allowed to bind to beads that had been covered with a coating of fibronectin. When the membrane-bound beads were pulled by an optical tweezer, the resultant mechanical stimulus was transmitted into the cell interior. What response did this cause?

Each connexon in a gap junction is constructed of ___ connexin subunits.

You are investigating the interactions of integrin $\alpha$ and $\beta$ subunits and isolate the extracellular portion of an integrin as a soluble $\alpha$ / $\beta$ heterodimer. The heterodimer lacks the associated transmembrane and cytoplasmic domains normally present as part of the molecule. You experimentally link the $\alpha$ and $\beta$ subunits at the bases of their legs so that the ligand-binding regions of the $\alpha$ and $\beta$ subunits approach one another and the legs are in the bent conformation. Which of the following statements is the best prediction of what will happen?

The green algae which first grew in a terrestrial environment are called ______________

What type of cell adhesion molecule is associated with formation of adherens junctions?

You disaggregate cells from two different developing organs and mix them together. Initially, they form a mixed clump. What happens next?

All collagen family members consist of _____ chains arranged in a _______ in at least part of their length.

What structure accounts for the fact that plants lack the specialized junctions seen in animal cells?

You coat a Petri dish with fibronectin and proteoglycans and then culture cells on the dish. The cells adhere to the dish. You repeat the experiment but this time add RGD tripeptides to the culture dish as the cells are added. What happens?