AP Bio
The approximate molarity of the solution in which the mass of the plant pieces would not change is
0.3 M
To model a plant cell, a permeable, nonflexible case is placed around each piece of dialysis tubing. The greatest pressure potential will develop within dialysis tube number
4
A net movement of water into the beaker occurs in which of the following dialysis tubes?
6
Intact cells of two unknown cell types were placed into solutions with different concentrations of NaCl. Type I cells swelled and burst in the solution with the lowest concentration of NaCl. Type II cells swelled but did not burst in the solution with the lowest concentration of NaCl. Which of the following descriptions of cell type I and cell type II are most consistent with the data?
A Cell Type I Animal cell surrounded by a plasma membrane only Cell Type II plant cell surrounded by a plasma membrane and a cell wall
The investigation is aimed at understanding how molecular size affects movement through a membrane. Which of the following best represents the amount of starch, water, and glucose in the dialysis bag over the course of the investigation?
A graph with x-axis labeled time and y-axis labeled relative amount in dialysis bag.The amount of starch remains constant. The amount of water starts below the amount of starch, increases to above the amount of starch and flattens out. The amount of glucose starts at higher than the amount of the starch, decreases to less than the amount of starch and flattens out.
The active transport pump used to move sodium ions across the membranes of gill cells in a freshwater fish has each of the following characteristics EXCEPT:
A it uses osmosis to carry sodium ions into the cells.
A pathogenic bacterium has been engulfed by a phagocytic cell as part of the nonspecific (innate) immune response. Which of the following illustrations best represents the response?
A phagocytic cell. A bacterium is engulfed by the cell. A lysosome finds and fuses to the phagosome containing the bacterium. After the lysosome interacts with the phagosome it is depicted to contain small particles. The phagosome attaches to the outer membrane of the phagocytic cell and releases the particles outside the cell.
Which of the following components of the cell membrane is responsible for active transport?
B Protein
If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is also inhibited?
C Passage of a solute against its concentration gradient
Site of transport of materials into and out of the cell
D
Dialysis tubing is permeable to water molecules but not to sucrose.The contents of which dialysis tube are initially isotonic to the distilled water in the beaker?
E. 5
If, instead of the bag, a potato slice were placed in the beaker of distilled water, which of the following would be true of the potato slice?
It would gain mass.
The manner in which several different ions and molecules move through a cell membrane is shown in the diagram above. For each ion or molecule, the relative concentration on each side of the membrane is indicated. Which of the following accurately describes one of the movements taking place?
Na+ transport out of the cell requires ATP hydrolysis.
The salinity of a small inland lake has recently started to increase. Researchers are planning to study the lake over several decades to investigate how freshwater organisms survive significant changes in their natural habitat. Which of the following physiological mechanisms will the researchers most likely observe among the surviving organisms in the lake?
Single-celled organisms will use various mechanisms to counteract the increased flow of water from cells to the environment.
Which of the following is the dependent variable in the experiment?
The absorbance of 460 nm light by the treatment solutions
Which of the following best describes the condition expected after 24 hours?
The bag will contain more water than it did in the original condition.
Intravenous (IV) solutions administered to patients are normally isotonic. Which of the following is most likely if an IV of distilled water is administered to a patient?
The cells that are exposed to hypotonic solutions will expand as water moves osmotically into the cells from the blood.
Paramecia are unicellular protists that have contractile vacuoles to remove excess intracellular water. In an experimental investigation, paramecia were placed in salt solutions of increasing osmolarity. The rate at which the contractile vacuole contracted to pump out excess water was determined and plotted against osmolarity of the solutions, as shown in the graph. Which of the following is the correct explanation for the data?
The contraction rate increases as the osmolarity decreases because the amount of water entering the paramecia by osmosis increases.
The illustration above is a model of a typical beet root cell. Based on the experimental results, which of the following best represents the effect of acetone on the permeability of cellular membranes?
The figure shows two models of a cell with a right-facing arrow between the two cells. The cell model on the left shows 4 Betacyanin Molecules inside the Vacuole. The cell model on the right shows 6 Betacyanin Molecules outside the Cell Wall three to the right and three to the left of the cell. The Vacuole membrane and the Plasma membrane are represented with dashed outlines.
What can be deduced from graph I?
The maximal flow of water through the stem lags behind the maximal rate of transpiration.
A human kidney filters about 200 liters of blood each day. Approximately two liters of liquid and nutrient waste are excreted as urine. The remaining fluid and dissolved substances are reabsorbed and continue to circulate throughout the body. Antidiuretic hormone (ADH) is secreted in response to reduced plasma volume. ADH targets the collecting ducts in the kidney, stimulating the insertion of aquaporins into their plasma membranes and an increased reabsorption of water. If ADH secretion is inhibited, which of the following would initially result?
The person would produce greater amounts of dilute urine.
From the initial conditions and results described, which of the following is a logical conclusion?
The pores of the bag are larger than the glucose molecules but smaller than the starch molecules.
The student analyzed the data from the investigation and concluded that the estimate of the mean of one treatment group was unreliable. Which of the following identifies the treatment group most likely to have provided an unreliable estimate of the mean, and correctly explains why the estimate appears unreliable?
Treatment group II; it has a lower than expected mean absorbance and the largest standard error of the mean.
Which of the following best predicts which diagrammed microscope view the laboratory worker would see and best explains why?
View 2 because the rate of water movement into the RBCs equals the rate of water movement out of the cells
Which of the following scientific questions is most relevant to the model represented in the figure above?
Which molecular substance is actively transported across the plasma membrane?
Which of the following graphs is the most appropriate representation of the experimental data?
Which of the following graphs is the most appropriate representation of the experimental data?
Based on the data from the investigation, which of the following is the best scientific question about organisms living in water that is polluted with organic solvents?
Will organisms living in polluted environments exhibit detrimental effects from an increased permeability of their cellular membranes?
When a substance moves across the plasma membrane along a concentration gradient at a rate faster than would be expected by simple diffusion alone but without the expenditure of metabolic energy, the process is best described as
facilitated diffusion
All of the following changes would be likely to decrease the rate of transpiration at 8 A.M. EXCEPT
increasing the water potential of the soil
Which of the following statements is true regarding the movement of substances across cell membranes?
ons are unable to move through the phospholipid bilayer because the nonpolar tail regions of the phospholipids are hydrophobic.
Water enters and leaves the plant cells primarily by
osmosis
