Cell Membrane and Homeostasis

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 solute outside the cell is higher than it is inside the cell.

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

Tags

NGSS.HS-LS1-3

What types of materials are expelled from cells during exocytosis?

• large molecules such as hormones

• positive and negative ions

• small molecules such as carbon dioxide

• water and glycerol

Algal cells are placed in an hypotonic solution. What happens to the cells?

• They will begin to swell.

• They will burst.

• They will stay the same.

• They will shrink.

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 process of the plasma membrane pumping excess sodium (a large molecule/energy is needed) out of a cell into an environment where there is a lower concentration of sodium is called _________.

• diffusion.

• osmosis.

• active transport.

• coupled transport.

What characteristic of the plasma membrane is illustrated in this drawing?

• selective permeability

• active transport

• fluid mosaic construction

• impermeability to water

A plant cell is placed in a hypotonic solution. What will happen to the plant cell?

• It will swell.

• It will shrink.

• It will stay the same.

• It will wilt.

Tags

NGSS.HS-LS1-3

What is a major difference between facilitated diffusion and active transport?

• Active transport moves substances against the concentration gradient.

• Active transport uses proteins in the process.

• Facilitated diffusion moves molecules through the plasma membrane.

• Facilitated diffusion requires large amounts of energy.

Which of the following is an example of passive transport?

• endocytosis

• exocytosis

• facilitated diffusion

• Na⁺/K⁺ ATPase pump

At what point in the process of diffusion is dynamic equilibrium reached?

• when the movement of the molecules

• when the molecules are mixed and stop moving

• when the rate of change in the solution slows by one half

• when there is continuous movement but no change in size of cell