Biology test

Which statement correctly describes the diagram?

The process in which carbon dioxide is used also forms glucose.

The vinegar was used to remove the shell form the raw egg. What other effect(s) did the vinegar have on the egg?

The vinegar solution was hypotonic, causing the egg to gain mass.

One student group's data for amount of yeast can be seen here. Describe the students' results.

There is a direct relationship between the amount of yeast and the rate of fermentation.

What process releases the least ATP per molecule of glucose for immediate cell use?

anaerobic respiration

The by-products of cellular respiration include

carbon dioxide and water

Transport of materials into a cell against a concentration gradient, from low to high, requires

energy.

This model shows a plant cell in a solution. Solutions can be hypotonic, hypertonic, or isotonic to the cell. Which one of the solutions tested demonstrates the water movement shown in the model?

Distilled water and vinegar

All of the following occur during the Krebs cycle EXCEPT: I. Acetyl-CoA combines with oxaloacetate to form citrate. II. FADH2 accepts two electrons to form FAD. III. NAD+ is reduced to form NADH. IV. Pyruvate is converted into acetyl-CoA V. Carbon dioxide, NADH, and FADH2, and ATP are reactants.

II, IV, and V

All BUT one product of the light dependent reaction of photosynthesis is utilized in the light independent reaction. That is

O2

Proteins are synthesized at the ribosome and are often modified en route to their destination. How are these modified proteins most likely transported within a compartmentalized eukaryotic cell?

Proteins are transported in vesicles between membrane-bound organelles.

Your lab group is experimenting with the diffusion of molecules across a membrane. Dialysis tubing is used as a model cell membrane, because is it semi-permeable, allowing small molecules to cross the membrane, but NOT larger molecules, like starch. A starch solution is placed in the dialysis tubing and then the dialysis tubing is placed in an iodine and water solution. Iodine is used as an indicator for the presence of starch. Normally, iodine is a yellow-brown color, but in the presence of starch, it turns a deep purple. After observing the experimental setup for 20 minutes, the iodine solution remains brown, but the starch solution inside the dialysis tubing is purple and swollen. Based on what you learned from the lab, starch is MOST likely to cross the cell membrane at which of the points indicated on the diagram?

Starch crosses the cell membrane at E.

Which statement concerning osmosis and active transport is correct?

Active transport requires cell energy while osmosis does not.

Describe the movement of molecules in the illustration.

Molecules are moving from a higher concentration to a lower concentration.

Biology students used raw eggs in an experiment on tonicity and osmosis. The students put their eggs into vinegar to remove the shells. The vinegar was used to remove the shell from the raw egg. What other effect(s) did the vinegar have on the egg?

The vinegar solution was hypotonic, causing the egg to gain mass.

The experimental set up shows the change in the color after copper sulfate crystals are put into a beaker of water. Observations verify that

copper sulfate spreads out through the water as a result of diffusion.

Receptors that are __________ bind to chemicals outside of the cell, and this binding process causes a chemical response on the inside of cells.

proteins

Based on the data, which gummy bear was in the salt solution and what was the tonicity of that solution?

C; hypertonic

Mr. Miller's biology class is studying cellular respiration. To model cellular respiration, they set up an experiment containing four flasks. Each flask is the same size and are stoppered and placed under a floodlight. Each flask also contains 200 mL of H20 and 2 mL of bromothymol blue. Bromothymol blue is a chemical indicator solution that changes color from blue to yellow in the presence of CO2. The students then place a plant and fish into each flask according to the table above. Which flask(s) will turn yellow and why?

Flask 2 (only) because the fish produce CO2 as products of cellular respiration and do not undergo photosynthesis therefore not consuming CO2.

During the light dependent reaction of photosynthesis, ________ is decomposed to supply hydrogen ions to produce NADPH, and important energy-carrying molecule used to help produce glucose during the light independent reaction.

H2O

Prior to the start of the experiment, the students hypothesized that both the vinegar and Kayro syrup solutions would be hypertonic to the contents of their eggs. The student data can be seen in the data table above. Does this data confirm their initial hypothesis? Explain.

No. The egg in vinegar had an increase in mass therefore vinegar would be hypotonic to the egg's contents.

A typical egg contains about 2% dissolved solids. Douglas places de-shelled eggs in four unknown solutions provided by his biology teacher. Based on this fact, predict which solution contains 10% saltwater, from the observations of the egg.

Solution c

Your lab group is experimenting with the diffusion of molecules across a membrane. Dialysis tubing is used as a model cell membrane because is it semi-permeable, allowing small molecules to cross the membrane, but NOT larger molecules, like starch. A starch solution is placed in the dialysis tubing and then the dialysis tubing is placed in an iodine and water solution. Iodine is used as an indicator for the presence of starch. Normally, iodine is a yellow-brown color (on the left), but in the presence of starch, it turns a deep purple (right). After observing the experimental setup for 20 minutes, the iodine solution remains brown, but the starch solution inside the dialysis tubing is purple and swollen. What CANNOT be concluded from the results?

Starch requires ATP energy for transport and therefore cannot cross the dialysis tubing into the iodine solution.

________________ are reactants in the process of cell respiration.

Sugar and oxygen

The figure shows a classic experiment that demonstrates the principle of osmosis. The left side of the U-tube is filled half-way with 10% red sugar water. Into the tube on the right, distilled water is poured until it is even with the red sugar water. A semi-permeable membrane is placed in the brown area. Predict what will happen in the U-tube after several hours.

The left side of the tube will remain red, but rise in volume, as the right side of the tube falls in volume. The distilled water will dilute the sugar water.

A simple dialysis tubing setup is shown above. The left image shows the original experimental setup and the right image shows the effects after twenty minutes. What description explains the movement of particles through the dialysis bag?

The membrane is permeable to the solvent and dialysate, but not to the protein.

Shaquan placed a potato slice in salt water. After some time he noticed that the slice of potato became limp. Why did this happen to the potato slice?

The potato cells lost water to the surroundings.

In the lab, students are soaking potato cores in different sucrose solutions overnight to observe the movement of water into and out of the potatoes. Observe the picture. Which result, below, best matches the picture?

The potato in the 2M solution remained the same because it was an isotonic solution.

To study osmosis, a student placed a thin potato slice in a salt solution. The slice became soft and shriveled. Then, he placed the shriveled slice in water. The slice regained its original shape. Based on the observations, which of these statements is correct?

The potato slice shriveled because water moved out of the slice into the salt solution.

Students performed a laboratory experiment to determine the molar concentration of red potatoes. They cut cubes from a whole red potato and massed them. They placed the cubes into various sucrose solutions, whose molar concentrations are shown above. The students then removed the potato cubes from the solutions twenty-four hours later and massed them again. They calculated the percent change for the potatoes in the various solutions. All of the data is displayed above. What is the approximate molar concentration of the red potatoes used in this experiment?

The red potatoes have approximately a 0.37 M solute concentration because this is where the potatoes would neither gain nor lose mass.

Some inquisitive students found two slugs and wanted to take them to science class. The only container they could find was a used potato chip bag. The students stored the slugs in the bag to take to school the next day, When the students opened the bag at school, they found that the slugs had melted and turned to slime. Why did this happen?

The salt around the slugs created a hypertonic environment, which caused water to diffuse out of cells and the cells will shrink.

Based on the results, what type of solution is the salt water?

The salt water is isotonic because there is no mass change in the egg.

The central vacuole in a plant cell is responsible for turgor pressure. When the vacuole loses water the cytoplasm "shrinks". When the vacuole gains water the cytoplasm seems to "puff up". One structure helps the plant cell keep its shape no matter how much water is in the vacuole. This is the

cell wall.

The passage states that organisms that live in fresh water cannot survive in salt water. These organisms will undergo a process termed plasmolysis. An organism experiencing plasmolysis would resemble the egg subjected to which variable of the experiment?

egg in Kayro syrup

According to the text, we might expect to find this egg to have been in which solution?

egg in syrup

During diffusion, molecules move

from higher concentration to lower concentration.

When a raw, shell-less egg was placed in sugar solution, the egg shrank. The egg was brought back to its original size by placing it in water. Which process does the experiment demonstrate?

osmosis

Which process moves water molecules across the membrane of a cell?

osmosis

Considering the chemical reaction for cellular respiration, what must be included in the respirometer containing the germinating seeds?

oxygen

The process of respiration is essential in the oxygen/carbon dioxide cycle. Respiration removes ______ from the atmosphere and produces and releases ______ to the atmosphere.

oxygen, carbon dioxide

Students hypothesized that adding ______________to a sixth test tube would produce the greatest amount of carbon dioxide.

warm water, yeast, and lactose.

Which of these chemicals is needed in order for the metabolic reactions of photosynthesis to occur?

water