AP Bio: Unit II Test (Ch. 6-7)

Mitochondria are found in most eukaryotic cells and contain their own DNA and ribosomes that are similar to those typical of many prokaryotic cells. Which of the following statements is justified by these observations?

A. An ancestral cell most likely englfed an aerobic prokaryote in a relationship that proved beneficial for both cells

Which of the following provides the weakest evidence that mitochondria were once free-living prokaryotes?

A. Mitochondria and prokaryotes both are found in a variety of sizes

(Diagram) The manner in which several different ions an 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?

A. Na+ transport out of the clel requires ATP hydrolysis

If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is also inhibited?

A. Passage of a solute against its concentration gradient

Prokaryotic and eukaryotic cells generally have which of the following features in common?

A. Ribosomes

Carbon dioxide most likely enters a cell through which of the following processes?

A. Simple diffusion through the membrane

(Diagram) The figure above represents a rough endoplasmic reticulum. Which of the following best describes the role of the structure labeled Y

A. Structure Y is the olcation where proteins are synthesized

Which of the following best explains how the phospholipid bilayer of a transport vehicle contributes to cellular functions?

A. The phospholipid bilayer allows the vesicle to fuse with the Golgi apparatus and the plasma membrane, allowing the exocytosis of proteins

(Peeled grape student experiment related question) Which of the following best explains why larger grapes have a different rate of water absorption per gram of mass than smaller grapes do?

A. The rate is slower bc smaller grapes have a larger surface-area-to-volume ratio than the larger grapes do

Water passes quickly through cell membranes because

A. it moves through aquaporins in the membrane

(FRQ 1) The following data were collected by observing subcellular structures of three different types of eukaryotic cells. "Relative Amounts of Organelles in Three Cell Types" Cell Type. Smooth ER. Rough ER. Mitochondria. Chloroplast. Golgi Bodies A. Large Amount. Small Amt. Small #. Absent. Small Amt B. Small Amt. Large Amt. Small #. Absent. Large Amt C. Small Amt. Small Amt. Small #. Large Amt Small Amt Based on the analysis of the data, identify a likely primary function of each cell type an explain how the data support the identification.

A: A likely primary function = production of lipids, or detoxification. It has a large amount of Smooth ER, which is involved in these functions. B: Likely primary function = protein production. It has a large amount of both RER and Golgi bodies, which are both involved in protein synthesis. C: Likely primary function = photosynthesis, and is also a plant cell. It contains chloroplasts which are involved in this function and are also present only in plant cells.

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from

B. A plant or an animal

Grana, thylakoids, and stromatolites are all components found in

B. Choloroplasts

(Peeled grape student experiment related question) Based on Table 1, which of the following best explains the difference in water potential between certain solutions and the grapes?

B. Grape soda and NaCl have a lower water potential bc these two solutions caused the grape to lose water

Which of the following best explains why a cell's plasma membrane is composed of two layers of phospholipids rather than just a single layer?

B. Havin two oppositely oriented layers of phospholipids allows only the hydrophillic heads to interact with water inside and outside of the cell

Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a salt solution become limp and soft. From this we can deduce that the cells of the celery stalks are

B. Hypertonic to fresh water but hypotonic to the salt solution

A student using a light microscope observes a a cell and correctly describes it is a plant cell because

B. It has a large central vacuole

Membranes are components of all of the following EXCEPT a

B. Microtubule

If red blood cells cultured in isotonic medium are placed in distilled water, they will most likely

B. Swell and lyse

A scientist designed an experiment to test an artificial membrane that mimics the phospholipid bilayer of a cell. [the scientist built a tub that was divided by an artificial membrane and filled with distilled water. The scientist put a known amount of a protein into the water on one side of the membrane. After some time, the scientist measured the concentration of the protein on either side of the membrane but found that there had been no change] Which of the following experimental changes would allow the scientist to observe transport of a solute across the artificial membrane?

B. Use a small, non-polar solute instead of a protein

(Peeled grape student experiment related question) Based on Table 1, which of the following percentages is closest to the solute concentration of the grape?

C. 5.5%

A cell is treated with a drug that prevents the formation of new lysosomes. The cell continues to transcribe the gene that code for hydrologic enzymes that are normally found in lysosomes and continues to translate mRNAs for those proteins on membrane-bound ribosomes. The hydrologic enzymes are most likely to accumulate in which of the following cellular structures?

C. Golgi complex

(Diagram) Which of the following is true about the structure of the prokaryotic cell represented in the figure?

C. It has a cell wall exterior to the plasma membrane an contains ribosomes

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization?

C. Lysosome

White blood cells engulf bacteria through what process?

C. Phagocytosis

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?

C. Smooth ER

Which of the following organelles modifies and packages for secretion the materials produced by the ribosomes?

C. The Golgi apparatus

Simple diffusion and facilitated diffusion are related in that both

D. Depend on a concentration gradient

A protein is synthesized in the cytoplasm and transported to the plasma membrane. Which of the following summarizes the protein's pathway in the cell?

D. RER —> Golgi complex —> vesicle —> plasma membrane

(Peeled grape student experiment related question) Assuming a negligible pressure potential, which of the following best predicts the net movement of the small diffuse level solutes and water in the second experiment (Table 2)?

D. Small diffusible solutes will diffuse into the grape cells and water will diffuse out of the cells

(Peeled grape student experiment related question) A student hypothesizes that the solute concentration of grape juice is higher tan the solute concentration of the actual grape bc the grape juice has added sugar. Based on the data in Table 1, which of the following best evaluates the student's hypothesis?

D. The hypothesis is not supported bc the mass fo the grape increased in the grape juice

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

E. Proteins

(FRQ 2) The following experiment was designed to test whether different concentration gradients affect the rate of diffusion. In this experiment, four solutions (0% NaCl, 1% NaCl, 5% NaCl, and 10% NaCl) were tested under identical conditions. 15 milliliter of 0% NaCl were put into a bag formed of dialysis tubing that is permeable to Na+, and Cl-, and water. The same was done for each NaCl solution. Each bag was submerged in a separate beaker containing 300mL of distilled water. The concentration of NaCl in mg/L in the water outside each bag was measured at 40 second intervals. The result from the 5% bag are shown in the table below. TIME (Sec). NaCl (mg/L) 0. 0 40. 130 80. 220 120. 320 160. 400 a. On the axes provided, graph the data for the 5% NaCl solution (3pts) b. Using he same set of axes, draw and label 3 additional lines representing the results that you would predict for 0% NaCl, 1% NaCl, and 10% NaCl solutions. Explain your predictions. (4pts)

a. Title: 5% bag concentrations Y-axis: NaCl (mg/L) X-axis: Time (seconds) Use table to graph the points b. 0%: straight along the x-axis 1%: same general trend as the 5% but below 10%: ^ but above Explanation: The NaCl concentration in the water outside the bag increased as time passed, meaning the NaCl was moving from areas of high to low concentrations, so the other solutions would also see an increase in NaCl concentration outside the bag as time passed, except for the 0% bag, as there is no NaCl. Since the 10% bag has a higher concentration of NaCl, it will have a larger concentration of NaCl in the water outside the bag as time passes than the 5% bag. Since the 1% bag has a lower concentration of NaCl, it will have a lower concentration o NaCl in the water outside the bag as time passes than the 5% bag.

Students were using the formulas for the surface area and volume of a rectangular solid to model cells of different sizes and shapes. They produced the data shown in the Table. Rect. solid. Length. Height. Width. SA. V. SA-V Ratio 1. 2.00 1 1 10 2 5 2. 2.67 .5 1.5 12.18 2 6.08 3. 4.00 .25 2 19 2 9.50 4. 6.05 .13 2.65 34.24 2 17.09 5. 10.68. .06. 3. 65.79. 2 32.85 a. IDENTIFY the rectangular solid that represents the cell with the smallest amount of plasma membrane per volume of cytoplasm b. DESCRIBE the relationship between the dimensions of the rectangular solids and their SA-V ratios c. Using the data from the model, EVALUATE the hypothesis that cells shaped like rectangular solids 1 and 2 are better suited for slow metabolism and the long-term storage of energy-containing molecules than are cells shaped like rectangular solids 4 and 5. d. Based on the trends shown in the data, EXPLAIN why some rectangular cells include folds or projections in their plasma membranes.

a. Rectangular solid 1 —> it has the smallest surface area-to-volume ratio b. X c. X d. Some rectangular cells include folds or projections in their plasma membrane to increase their SA, which wold also increase the SA-to-V ratio