AP BIO Unit 2 FRQs

Graph these data on the axes provided. From your graph, find the apparent molar concentration (osmolarity) of the potato core cells.

.36 M

Identify FOUR organelles that should be present in the eukaryotic organism and describe the function of each organelle.

ribosomes - protein synthesis Smooth endoplasmic reticulum- lipid synthesis or detoxification Cilia- movement Mitochondria- ATP synthesis

Based on Figure 1, describe the direct source of energy used to move glucose into the epithelial cell from the intestinal lumen. Explain how this system maximizes glucose absorption from the intestinal lumen into the epithelial cells and from the epithelial cells into the blood.

- Energy from the sodium gradient - The Na+/K+ pump maintains the sodium concentration gradient and allows for the contransport of glucose. - The microvilili/folds on the lumen side of the epithelial cell provide more surface area for uptake of glucose into the epithelial cell.

Movement of water and nutrients is critical for the survival of plants. Using the concept of water potential, explain the role of positive and negative pressure in the transport of water and nutrients throughout a vascular plant.

- Water moves from areas with high water potential to areas with low water potential - Loss of water from leaves to the atmosphere due to lower water potential of the air (transpiration) - Root pressure (positive pressure) develops as ions enter the xylem, lowering water potential and causing osmosis into the xylem - Phloem cells accumulate sugars, which lowers the water potential of phloem cells

Identify the cellular location where cytochrome bis is most likely found.

10^-3 (uM)

Using the data, determine the molar concentration of chicken egg cytoplasm and justify your answer.

Correct molar concentration based on graph -0.32M (0.3M to 0.5M) Explanation: When y = 0, no change in mass = no net water movement = isotonic = solute concentration inside egg and outside egg are the same

Identify the most likely cellular location of a mutant CFTR protein that has an amino acid substitution in the ATP-binding site.

In the plasma membrane

Predict what would happen to typical animal cells placed in 0.0 M and 1.0M sucrose solutions, and explain your prediction.

It will cause the cell to gain water and gain mass causing the cell to swell or burst.

Endosymbiosis has been proposed as a model for the evolution of eukaryotic cell structure. Identify and explain TWO pieces of evidence that support the endosymbiotic theory.

Mitochondria and chloroplasts have their own DNA Mitochondria and chloroplasts can self replicate

According to the endosymbiotic theory, some organelles are believed to have evolved through a symbiotic relationship between eukaryotic and prokaryotic cells. Describe THREE observations that support the endosymbiotic theory

Mitochondria contain their own dna Chloroplasts contain their own dna Mitochondria can self replicate

In the provided model of a cell, draw arrows to describe the pathway for production of a normal CFTR protein from gene expression to final cellular location.

Nucleus-- ER---- Golgi---plasma membrane

Prokaryotic cells lack membrane-bound organelles found in eukaryotes. However, prokaryotes must perform many of the same functions as eukaryotes. For THREE of the organelles identified in part (a), explain how prokaryotic cells carry out the associated functions.

Ribosomes- site of protein synthesis Smooth er- lipid synthesis or detoxification occurs in the cytosol Cilia- motility via bacterial flagella

Identify the most likely cellular location of the ribosomes that synthesize CFTR protein.

Rough ER

Identify the cellular component in the model that is responsible for the increase in of the vacuole during flower opening AND describe the component's role in changing of the vacuole.

The K+/H+ transport protein is responsible for the increase in the vacuole during the flower opening. It moves H+ out of the vacuole which changes the vacuole.

Using the experimental results, describe the pathway that secretory proteins take from their synthesis to their release from the cell.

The pathway that the secretory proteins take from their synthesis to their release from the cell is the nucleus, to the ER, to the Golgi apparatus then finally leaving the cell through the plasma membrane.

A researcher claims that the activation of the transport protein causes the vacuole to swell with water. Provide reasoning to support the researcher's claim.

The concentration of solute (K+) is increasing inside the vacuole. The solute (K+) is moving into the vacuole, making it hypertonic, lowering the water potential.

Based on the pedigree in Figure 1, predict the probability that the individual marked by a "? " will have the skin disorder. Justify your prediction.

The individual marked by the "?" have a 50% chance of skin disorder. According to the Pedigree, the disease is dominant in the male offspring. If the trait is dominant in the person they will show the disease. If it is recessive in them they carry the trait but it doesn't show the disease. The mother is not infected so she carries the trait but doesn't show the disease so there is a 50% chance the remaining child will get the disease.

Explain how the folding of the mitochondrial inner membrane and the many individual chloroplast thylakoids are beneficial to a cell that is carrying out chemical reactions.

The folding of the membrane increases the surface area, as does the thylakoids. With more surface area, more reactions are able to take place.

Describe how increasing salinity affects the amount of fluid ejected each time a contractile vacuole contracts. Calculate the water potential ( ) of an animal cell without contractile vacuoles if water enters the cell and creates a solute potential ( ) of -2. Assume that the pressure potential ( ) in the cell is 0.

The higher the salt contraction, the lower the rate of contractile vacuole concentration. -2+0= -2 WP

Describe the importance of the inner membranes separating different regions of the mitochondrion and the chloroplast.

The inner membranes allow the organelles to compartmentalize because of increased folds, therefore, increasing surface area and efficiency.

Describe the characteristics of an aquaporin protein that enable it to extend from the cytoplasm through the membrane into the extracellular space. If isolated keratinocytes are placed in a hypertonic solution for hours,explain the net direction of water movement AND why the rate of water movement slows down over time.

The interior aquaporin channel proteins embedded in the membrane are like tunnels. It is hydrophilic so it allows water to flow across the membrane. It is designed specifically for water molecules and excludes glucose. If isolated keratinocytes are placed in a hypotonic solution for 24 hours the more water will be depleted and the smaller the amount of water in a cell the slower the rate of movement.

Based on the diagram, describe how the structure of these organelles controls movement across the membranes.

The molecules would first pass through the first membrane and stop, or continue to pass through the second and third membrane.

Using the most appropriate data, construct a labeled graph on the axes provided below to best illustrate water movement into and out of the egg.

Title, labels of axes (X must be molar concentration, Y may be change in mass or % change in mass)

Describe how the phospholipids of a plasma membrane regulate the movement of large or polar molecules across the membrane. Explain how osmosis will affect animal cells when the cells are placed into an environment with a low water potential (high solute concentration) compared to the intracellular water potential.

The phospholipids do not allow large or polar molecules to enter the plasma membrane. Polar and large molecules can pass through passive and active transport. Osmosis will affect animal cells that are placed in low water potential with high solute concentrations compared to the intracellular water potential to shrink because it is in a hypertonic environment.

Explain how aquaporins that are inserted into one area of the plasma membrane are distributed to other parts of the plasma membrane.

The rough ER is responsible for the synthesis and transportation of the aquaporin polypeptides from the Mrna and the golgi apparatus modifies it.

A scientist claims that the presence of aquaporins in chloroplast membranes supports the endosymbiotic theory. Support The claim with evidence from biological concepts.

The scientist is claiming that chloroplast membrane absorbed aquaporins. This evolution shows evidence because aquaporins are instrumental to the chloroplast membrane which backs the endosymbiotic theory.

Complete the table to represent the relationship between volume and surface area of a spherical structure surrounded by a membrane.

just remember that the ratio is 1:3 and 1:1

Explain why there is a difference in percent of mass change of the eggs in the different sucrose solutions.

— Egg gains mass if solute concentration is lower outside of egg (hypotonic) causing water to move into egg — Egg loses mass if solute concentration is higher outside of egg (hypertonic) causing water to move out of egg — Water moves from low solute/high water concentration to high solute/low water concentration