Chapter 7 - notes PDF

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Water passes quickly through cell membranes because rins in the membrane.

The movement of the hydrophobic gas, nitrous oxide (N2O) (laughing gas) into a cell is an example of bilayer.

An organism with a cell wall would most likely be unable to take in materials through

The difference between pinocytosis and receptor-mediated endocytosis is that s is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.

In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis? of the vesicle

Which of the following types of molecules are the major structural components of the cell membrane? ns

The presence of cholesterol in the plasma membranes of some animals animal more susceptible to circulatory disorders.

In order for a protein to be an integral membrane protein it would have to be ic, with at least one hydrophobic region.

When a membrane is freeze-fractured, the bilayer splits down the middle between the two layers of phospholipids. In an electron micrograph of a freeze-fractured membrane, the bumps seen on the fractured surface of the membrane are

The cell membranes of Antarctic ice fish might have which of the following adaptations? a high percentage of polyunsaturated fatty acids

In facilitated diffusion, what is the role of the transport protein? Transport proteins provide a protein site for ATP hydrolysis, which facilitates the movement of a solute across a membrane. Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that

the fresh water is isotonic and the salt solution is hypertonic to the cells of the celery stalks.

Mammalian blood contains the equivalent of 0.15 M NaCl. Seawater contains the equivalent of 0.45 M NaCl. What will happen if red blood cells are transferred to seawater? Water will leave the cells, causing them to shrivel and collapse.

A patient was involved a serious accident and lost a large quantity of blood. In an attempt to replenish body fluids, distilled water–equal to the volume of blood lost–is added to the blood directly via one of his veins. What will be the most probable result of this transfusion?

The patient's red blood cells will swell and possibly burst because the blood has become hypotonic compared to the cells.

If the concentration of phosphate in the cytosol is 2.0 mM and the concentration of phosphate in the surrounding fluid is 0.1 mM, how could the cell increase the concentration of phosphate in the cytosol? active transport Active and passive transport of solutes across a membrane typically differ in which of the following ways? Active transport is usually down the concentration gradient of the solute, whereas passive transp solute.

What is the voltage across a membrane called? membrane potential Which of the following processes includes all others? passive transport Which of the following molecular movements is due to diffusion or osmosis?

When a plant cell is placed in concentrated salt water, water moves out of the cell.

\ What happens when two solutions separated by a selectively permeable membrane reach osmotic equilibrium?

Water molecules move between the two solutions, but there is no net movement of water across the mem...