Active and Passive Transport

If the concentration of a sugar solution is lower outside the cell than inside the cell, which of the following will happen by osmosis?

• Water will move out of the cell

• Water will move into the cell

• Sugar will move out of the cell

• Sugar will move into the cell

How is the plasma membrane of a cell organized?

• one layer of phospholipids, through which proteins freely move

• one layer of phospholipids, which are laid out end-to-end, with a hydrophobic tail touching a hydrophilic head

• two layers of phospholipids, each of which has its hydrophilic side turned inward

• two layers of phospholipids, with their polar hydrophilic heads facing away from each other

The diagram below represents a cell in water. Explain why more water is moving out of the cell than into the cell.

• The concentration of solute in the cell is higher than it is outside the cell.

• The concentration of water outside the cell is too great.

• The concentration of water inside the cell is greater than it is outside the cell.

Homeostasis is the process of maintaining a cell’s environment. This includes the regulation of sodium ion (Na+) concentration within the cytoplasm. If too much Na+ is inside a cell, how can the concentration be changed?

• More Na+ ions will enter the cell through the plasma membrane.

• Excess Na+ ions will leave the cell via osmosis.

• Excess Na+ ions will be transported out through membrane protein channels.

• More Na+ ions will be transported in through membrane protein channels.

Which way would the purple molecules move through the semi permeable membrane?

• From side A to the side B.

• From side B to the side A.

• The purple molecules would not move.

Based on these results, which statement correctly predicts what will happen to red blood cells when they are placed in a beaker containing a water solution in which the salt concentration is much higher than the salt concentration in the red blood cells?

• The red blood cells will absorb water and increase in size

• The red blood cells will lose water and decrease in size.

• The red blood cells will first absorb water, then lose water and maintain their normal size.

• The red blood cells will first lose water, then absorb water, and finally double in size.

Nemo and other ocean dwelling fish cannot survive in freshwater because......

• freshwater is hypertonic to Nemo's cells and will result in water leaving them causing the cells to shrink

• freshwater is hypotonic to Nemo's cells and will result in water leaving them causing the cells to shrink

• freshwater is hypertonic to Nemo's cells and will result in water entering them causing the cells to swell and burst

• freshwater is hypotonic to Nemo's cells and will result in water enter them causing the cells to swell and burst

What structure is labeled A

• Marker Protein
• Receptor Protein
• Phospholipid
• Cholesterol

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which of the following has occurred?

• The swollen gums have absorbed the saltwater solution.
• The saltwater solution lowers the temperature of the water in the gums.
• The salt in the solution has moved against the concentration gradient.
• The water in the gums has moved out due to the high concentration of salt in the solution. 

How does oxygen enter blood cells in the lungs?

• Active transport

• Bulk transport

• Facilitated transport

• Simple diffusion