Exam 11: Cellcell Interactions

Anorganic bone matrix ABM) is a material commonly used in bone grafts. Scientists compared ABM with ABM- peptide. The peptide that was bound to ABM was 15 amino acids long, derived from the extracellular matrix molecule, collagen. The researchers found that anchorage- dependent cells were more likely to adhere to and grow on the ABM- peptide than on ABM alone. What conclusion might be drawn from this research?

All of the following can be proteins found in the extracellular matrix of animal cells EXCEPT

Put the following events in the process of signal- transduction in order: 1) A conformational change in the signal- receptor complex activates an enzyme. 2) Protein kinases are activated. 3) A signal molecule binds to a receptor. 4) Target proteins are phosphorylated. 5) Second messenger molecules are released.

Why are receptors for steroid hormones located inside the cell rather than on the membrane surface?

Blood sugar is regulated by two pancreatic hormones, namely insulin and glucagon. When blood sugar rises, insulin is released; it binds to receptors and, through signal transduction, results in an increase in glucose uptake by cells, effectively lowering blood glucose. When blood sugar decreases, glucagon is released, binds to cell receptors, and causes glucose to be released into circulation. Diabetes mellitus is a disorder that results from excessively high levels of blood glucose. Type II diabetics have normal to elevated levels of insulin. What, then, might be causing the elevated blood glucose levels?

Signals from the extracellular matrix to the cytoskeleton may be transmitted by

One characteristic of life and living systems is that they are able to adapt. Toward this end, cells interact with other cells and their environment through the action of their

A kinase is an enzyme that

Which component is a protein fibre of the extracellular matrix?

Integrins are integral membrane proteins. They are often attached to

Where would you expect to find tight junctions?

Which of the following best describes the function of gap junctions?

What do the cell walls of plants and the extracellular matrix of animal cells have in common?

What is the function of the middle lamella in plant cells?

For a tissue or an organ to function as a unit,

The fact that a single signal- receptor complex results in the activation of several second messenger molecules enables the cell signal to be

Steroid hormones bind to receptors inside the cell and alter their conformation. The hormone- receptor complex is then transported into the nucleus, where it can directly affect gene expression. To get from the location where the receptor binds the hormone to its site of action, the receptor- hormone complex must

Which of the following would not be found in a plant cell?

Which of the following statements about quorum sensing is FALSE? Quorum sensing

Pemphigus vulgaris is an autoimmune disorder in which antibodies are produced against the cadherins of desmosomes. The blistering seen in these individuals is probably a result of