Chapter 3: Cells

Clicker Questionsby Kristen Curran, University of Wisconsin-Whitewater

Which feature below is only found in eukaryotic cells?

1. Ribosomes2. DNA3. Cell membrane4. Mitochondria

Which evidence below supports the theory that mitochondria and chloroplasts were originally bacteria?

1. Circular DNA is present in both organelles.

2. Both organelles are larger than other organelles in the cell.

3. Both organelles are surrounded by a single lipid bilayer.

4. All of the above.

Lipids that make up the cell membrane are hydrophobic. Hydrophilic molecules, like glucose, cannot cross this barrier. What major component of the plasma membrane helps glucose get into and out of the cell?1. Phospholipids2. Carbohydrates3. Nucleic acids4. Proteins5. Fatty acids

Classroom Catalyst

Membrane Fluidity and Cholesterol

Given the composition of the fictitious membranes below, which membrane is the most fluid?

1. 50% saturated fatty acids and 50% unsaturated fatty acids

2. 70% saturated fatty acid and 30% unsaturated fatty acid

3. 30% saturated fatty acid and 70% unsaturated fatty acid

4. 80% saturated fatty acid and 20% unsaturated fatty acid

Smallmouth Bass and Yellow Perch are considered warm water fish, whereas certain species of char are found in the arctic. Which fish do you think might have the most cholesterol in the membranes of its cells?

1. Smallmouth Bass2. Yellow Perch3. Arctic char4. Both 1 and 2 are

correct.

Which of the cell membrane functions below is possible due to the presence of proteins in the plasma membrane?

1. The cell membrane determines what molecules will enter or leave the cell.

2. The cell membrane contains proteins that can bind to messages sent from other cells and relay the message to the interior of the cell.

3. The cell membrane contains proteins that act as a fingerprint for distinguishing between self and foreign cells.

4. Both 1 and 2 are correct.5. All of the above.

An amoeba (a single-celled protist) is placed in a solution. The volume of the cell increases (cell swells). Which statement below is the correct interpretation of this result?1. The amoeba is in a hypertonic

solution.2. Water is moving into the

amoeba.3. The amoeba is in a isotonic

solution.4. Water is moving out of the

amoeba.

Classroom Catalyst

Passive vs. active transport

A normal cell has a high concentration of potassium on the inside and a low concentration of potassium on the outside. Also, a normal cell has a low concentration of sodium on the inside and a high concentration on the outside. Yet, the net movement of potassium is into the cell and the net movement of sodium is out of the cell. What type of transport is involved?

1. Osmosis2. Facilitated transport3. Active transport4. Simple diffusion5. Secondary active

transport

An intestinal epithelial cell powers the movement of glucose into the cell against its concentration gradient by simultaneously transporting sodium down its concentration gradient. Which transport mechanism is responsible?

1. Osmosis2. Facilitated transport3. Active transport4. Simple diffusion5. Secondary active

transport

When a woman nurses her baby, proteins are released from the mammary cells, accumulate in the ducts of the breast, and flow out of the nipple. Which process listed below is involved?

1. Phagocytosis2. Pinocytosis3. Receptor-

mediated endocytosis

4. Exocytosis

Your skin is water proof. What type of cell-cell junction is most likely involved in creating a water-tight barrier between the outside and inside of your body?

1. Tight junctions2. Desmosomes3. Gap junctions

Which cellular component would be responsible for the classic shape of a red blood cell?

1. Nucleus2. Cytoskeleton3. Lysosome4. Mitochondria

Which cells below would have the most smooth endoplasmic reticulum?1. Kidney cells2. Kidney cells of an

alcoholic3. Liver cells4. Liver cells of an

alcoholic

You can think of a cell as a car factory. The control center holds the directions for making the car. There are assembly lines for constructing the engine and frame of the car. After the main structure of the car is built, the finishing touches are added (paint, leather seats, chrome bumpers). Lastly, the car is shipped to different car destinations. Which organelle would be responsible for putting the finishing touches on the car (protein)?

1. Nucleus2. Ribosome3. Rough endoplasmic

reticulum4. Smooth endoplasmic

reticulum5. Golgi Apparatus

Which answer below is not found in a eukaryotic cell?

1. Cell wall2. DNA without membrane3. Endoplasmic reticulum4. Chloroplast5. Lysosome