Cell-ebrities
A pancreatic cell produces large amounts of digestive enzymes that must be secreted outside the cell. Which organelle would likely be especially abundant to modify and package these proteins?
What is the golgi apparatus
A scientist discovers that a membrane contains phospholipids with hydrophilic heads and hydrophobic tails. Which part of the membrane faces the cytoplasm and extracellular fluid?
What are the hydrophilic heads
A substance moves across a membrane from an area of high to low concentration without ATP. What type of transport is occuring?
What is passive transport
An animal cell is placed in a solution with a lower solute concentration than its cytoplasm. Predict what will happen to the cell.
It will swell due to water entering the cell by osmosis
Why do eukaryotic cells use membrane-bound organelles to separate different metabolic reactions?
Compartmentalization allows specialized conditions and reduces competing interactions.
A cell have a mutation that prevents ribosomes from attaching to the endoplasmic reticulum. Which cellular process would be most directly affected?
What is the synthesis of proteins destined for secretion or membranes
A researcher increases the concentration of cholesterol in an animal cell membrane. What is one major function of cholesterol in the membrane.
What is regulating membrane fluidity and stability
Glucose moves into a cell through a carrier protein, traveling down its concentration gradient without ATP. Identify the specific transport mechanism.
What is facilitated diffusion
A plant cell is placed in a hypertonic solution. Explain what happens to its central vacuole and plasma membrane.
The vacuole loses water and shrinks, and the plasma membrane may pull away from the cell wall (plasmolysis)
A researcher observes that prokaryotic cells lack membrane-bound organelles such as mitochondria. What does this suggest about how their cellular processes are organized?
They occur in the cytoplasm or at the plasma membrane instead of the membrane-bound organelles.
A drug damages the inner membrane of the mitochondria, reducing its surface area. Which cellular process would most likely decrease?
What is ATP production through cellular respiration
A molecule is small, but highly charged. Predict whether it can pass directly through the phospholipid bilayer and explain why.
No. Its charge prevents it from passing through the hydrophobic interior without a transport protein.
A cell uses ATP to pump sodium ions out and potassium ions into the cell against their concentration gradients. What protein is responsible?
What is the sodium-potassium pump?
Two cells have the same shape, but Cell A has a radius of 2μm and Cell B has a radius of 4μm. Which cell has a higher surface area-to-volume ratio, and why?
Cell A, because smaller cells have a greater surface area-to-volume ratio.
A scientist uses a chemical that prevents vesicles from fusing with the golgi apparatus. Predict what will happen to proteins traveling through the endomembrane system.
Protein modification, sorting, and trafficking will be disrupted.
A cell's lysosomes lose the ability to maintain an acidic environment. What would most likely happen to the cell?
What is a decrease in the activity of digestive enzymes, causing materials to accumulate.
A cell membrane loses several of its integral transport proteins. Which type of molecule would be most directly affected in its ability to cross the membrane?
What are ions and large polar molecules
A cell is unable to produce sufficient ATP. Predict how this will affect active transport and the cell's ability to maintain concentration gradients.
Active transport will decrease, causing ion gradients to weaken and disrupting cellular homeostasis
A cell is placed in an isotonic solution and then transferred to a hypertonic solution. Explain how the direction of water movement changes and why.
In an isotonic solution there is no net movement of water. In ther hypertonic solution, water moves out of the cell because the surrounding environment solution has a higher solute concentration. Causing the cell to shrink
A cell has a mutation that prevents aquaporins from functioning. Predict how this will affect water movement across the plasma membrane.
Water transport across the membrane will decrease, especially when rapid water movement is needed.
A researcher observes an organelle with its own DNA, ribosomes, and a double membrane. Explain which organelle it could be and what evolutionaty theory explains its origin.
What are mitochondria or chloroplasts, explained by the endosymbiotic theory?
A mutation changes the amino acid sequence of a membrane channel protein, altering its shape. Explain how this mutation could affect the cell's internal environment.
Disruption in selective transport, potentially changing ion concentrations, water balance, and membrane potential.
Exocytosis, involving vesicles fusing with the plasma membrane
An organism's body size increases significantly, causing its surface area-to-volume ratio to decrease. Predict one challenge this creates for the organism.
Harder to exchange materials and dissipate heat efficiently because surface area does not increase as quickly as volume.
A scientist treats cells with a substance that inhibits ATP synthase. Predict how this affects ATP production and explain one possible consequence for membrane transport.
ATP production will decrease, reducing ATP-dependent active transport and potentially disrupting ion gradients.