Biology review 3
A beaker is divided into two halves, A & B, by a membrane that is freely permeable to the water and NaCl but not to protein. Side A is half-filled with a solution of 8% protein, while side B is half filled with a 2% protein solution. Predict what would happen to side A after a few hours.
The number of water molecules has increased.
An osmosis investigation was conducted using chicken eggs to represent cells with semipermeable membranes. The mass of each egg was measured to determine how much water diffused into or out of the eggs. The eggs were first soaked in vinegar to dissolve the shell. Each egg was then placed in one of three different solutions for 24 hours. The table below shows the results of the investigation.Based on this experiment, which of the following should be inferred about cells with semi permeable membranes?
Water enters the cell when placed in environments of high water concentration.
Osmosis occurs when there is a different concentration of solute molecules on each side of the membrane. The drawing below shows a beaker containing a 30% salt solution and a suspended cell containing a 10% salt solution. What statement best describes the cell after 20 minutes?
Water will move from the cell into the beaker, resulting in a smaller cell.
Look at the cross section of a cell membrane of a eukaryotic cell. H+ ions are being pumped from a low concentration to a high concentration.How do you describe this type of transport across the cell membrane?
active transport
When Streptococcus pneumoniae are exposed to an antibiotic, the bacteria try to pump the antibiotic out of their cells. Which of the following mechanisms is most likely used by the Streptococcus pneumoniae to pump the antibiotic out of their cells?
active transport
Which means of particle transport is shown in this diagram?
active transport
Which means of particle transport requires input of energy from the cell?
active transport
Joy took the notes shown below while learning about cells.• Forms boundary between a cell and the outside environment• Controls the movement of materials into and out of the cell• Consists of double layer of phospholipids.She forgot to write the name of the cell structure that her class was studying that day. What structure is described in her notes?
cell membrane
Which of the following structures serves as the cell's boundary from its environment?
cell membrane
In pure water, a red blood cell from an animal will swell and burst, but a leaf cell from a plant will not. Which structure in the leaf cell is responsible for this difference?
cell wall
During diffusion, when the concentration of molecules on both sides of a membrane is the same, the molecules will
continue to move across the membrane in both directions.
Which means of particle transport is shown in this diagram?
exocytosis
Look at the diagram of a cross-section of a cell membrane below. The cell membrane controls movement of materials into and out of the cell. The following particles are moving from high concentration to low concentration and are using a carrier protein. How would you describe this type of movement across the membrane?
facilitated diffusion
In an emergency trauma room, a doctor accidentally gives a patient a large transfusion of distilled water directly into one of his veins instead of blood. Predict what might happen if distilled water was given to the patient instead of blood.
have serious, perhaps fatal effects because the red blood cells would tend to burst
Carrot sticks that are left in a dish of freshwater for several hours become stiff and hard. Similar sticks left in a saltwater solution become limp and soft. From this we can deduce that the freshwater is ______ and the saltwater is ________ to the cells of the carrot sticks.
hypotonic, hypertonic
The diffusion of water across a selectively permeable membrane is called
osmosis
The cell membrane contains channels and pumps that help move materials from one side to the other. What are these channels and pumps made of?
protein
Which of the following is a function of the cell membrane?
regulates the movement of materials into and out of the cell
The cell membrane of the red blood cell will allow water, oxygen, and carbon dioxide to pass through. Because other substances are blocked from entering, this membrane is called
semi-permeable
An animal cell that is surrounded by fresh water will burst because the osmotic pressure causes
water to move into the cell.
