The bond in table salt (NaCl) is
a. polar.
b. ionic.
c. covalent.
d. double.
e. nonpolar
B
You might also like to view...
As a tissue, blood is composed of only one type of cell
a. True b. False
Phillip is breathing at approximately 40 ventilations per minute. What is the respiratory center indicating?
Select one: a. low oxygen concentration in the lungs b. high carbon dioxide concentration in the blood c. low oxygen concentration in the blood d. the firing of the intercostal nerves e. stretch receptors in the alveolar walls
Read the following passage. Notice that there are numbers at the end of some of the sentences
Refer to these numbers when answering the question(s) below. Melanoma cells metastasize by leaving the primary tumor and entering the bloodstream, which carries them to distant parts of the body. The cancer cells leave the bloodstream by crossing the capillary basal lamina to enter another tissue (1). As a cancer researcher you think that somehow preventing the cancer cells from crossing the basal lamina of the blood vessels will inhibit metastasis (2). You believe that if you block the integrin receptors on the melanoma cells from binding to the extracellular matrix proteins of the basal lamina, then the cells will not be able to adhere to the basal lamina and therefore will not be able to migrate across it (3). You and your colleagues set about to make antibodies that will bind specifically to the integrins on the surface of the melanoma cells, preventing them from adhering to the proteins in the basal lamina. Once you have these integrin-specific antibodies, you test them on cancer cells in culture to see if they prevent the cells from crossing an artificial basal lamina. To do this, you and you colleagues set up nine cultures of cancer cells. You treat three cultures with the integrin-specific antibody. You treat three more cultures with a non-specific antibody that does not bind to integrins. Three cultures of cells are not treated with antibodies. (4). In the passage above, sentence number 2 is: A. support for their idea that blocking integrin function inhibits some tumor cells from binding the basal lamina. B. proof that their idea about blocking integrins will prevent metastasis. C. an observation. D. a prediction. E. a hypothesis.
Nuclear pores function as gateways for molecules to enter and exit a nucleus. Protein synthesis offers an example of why this movement is important. Explain
What will be an ideal response?