Exam 6: Cell Membranes

A student claims that cell recognition and cell adhesion refer to the same function.Which statement best evaluates this claim?

Root hair cells in plant roots use active transport to take up nitrate ions from the soil.Active transport is used because it requires energy to move nitrate ions from a _______ concentration in the soil into the plant cells.

Which molecule can function as a recognition signal for interactions between animal cells?

When a severely dehydrated patient is brought to the hospital, an intravenous drip of saline is started immediately.Sterile deionized water is not used because

Refer to the figure below. The figure shows the molecular structures of urea and diethylurea.Both molecules can pass through biological membranes via simple diffusion, but diethylurea will diffuse through a membrane at a rate 50 times greater than that of urea.This is because diethylurea is _______ nonpolar than urea.

Which is a correct pairing of a substance and the process by which it is transported across cell membranes?

Refer to the image below. In order to study the distribution of proteins within membranes from different types of cells, a researcher could use the _______ technique to generate images by electron microscopy, such as the one shown above.

All of the following processes occur in normal cell development and metabolism.Which pair of processes is most important during development when cells are aggregating into tissues?

Which is an example of passive transport?

If a shallow pan is filled with water, a drop of red ink is placed in one end of the pan, and a drop of green ink is placed in the other end, which of the following will be true at equilibrium?

Adjacent animal cells may be bound together by _______, _______, and _______.

Channels that run between pores of adjacent heart cells are called _______.

Phagocytosis, pinocytosis, and receptor-mediated endocytosis all involve

Refer to the figure below. The type of cell junction shown is most efficient in

A species of fish that lives in the ocean has cells with a lower solute concentration than the surrounding ocean waters.To maintain cell homeostasis under these conditions, these fish

Sponges are multicellular organisms whose bodies allow water to circulate freely.If isolated cells from one species were added to a solution of isolated cells from another species, what would you expect in terms of binding among the cells?

Refer to the figure below, which shows the results of an experiment in which cells from two different species were fused to form a single large cell.Membrane proteins labeled with different-colored dyes were observed and found to undergo mixing and become uniformly distributed after 40 minutes. The experiment was repeated at a lower temperature, and the same uniform distribution was observed, but it required a much longer time to achieve.These results indicate that temperature affects the _______ of a biological membrane.

Binding that occurs between different molecules on different cells that have an affinity for each other, such as a mammalian egg and sperm cell, is referred to as _______ binding.

Freeze-fracturing is a useful tool for revealing _______ proteins.

Studies of isolated animal cells mixed together randomly and then placed in culture dishes have shown that they sort themselves out according to the types of membrane proteins they express.The figure below shows an example of this sorting-out process. Explain the molecular basis for how cells sort themselves out and form attachments to one another in producing the end product shown.