CELL STRUCTURE
Which structure controls the movement of substances into and out of the cell?
Plasma membrane.
Name one major feature that distinguishes a prokaryotic cell from a eukaryotic cell.
A prokaryotic cell has no nucleus.
Which structure contains most of the genetic material in a eukaryotic cell?
Nucleus.
Why would a cell specialized for producing large amounts of ATP contain many mitochondria?
Mitochondria are the main site of aerobic respiration and ATP production.
A cell contains 70S ribosomes and has no nucleus or mitochondria. Is it more likely to be prokaryotic or eukaryotic and why?
Prokaryotic because Prokaryotic cells do not have a nucleus or membrane-bound organelles such as mitochondria. Their cytoplasmic ribosomes are 70S.
What type of ribosomes are found in the cytoplasm of prokaryotic cells?
70S ribosomes.
Name two membrane-bound organelles found in eukaryotic cells.
Any two: nucleus, mitochondria, Golgi apparatus, endoplasmic reticulum, lysosomes, or chloroplasts.
A student says: “All cells must have a nucleus because DNA needs to be protected.” Is this statement correct?
No.
Prokaryotic cells contain DNA but do not have a nucleus. Their DNA is located in a region of the cytoplasm called the nucleoid. Therefore, a nucleus is not required for a cell to contain or protect DNA.
Why is the inner membrane of a mitochondrion highly folded and what are these folds called?
Cristae, To increase surface area.
A drug prevents bacterial ribosomes from functioning. What cellular process would be directly affected?
Protein synthesis.
What is one major advantage of compartmentalization in eukaryotic cells?
It allows different processes to occur in specialized environments.
A cell produces large amounts of lipids rather than proteins. Which organelle would you expect to be particularly well developed?
Smooth endoplasmic reticulum.
The smooth ER is involved in lipid synthesis.
A cell produces and secretes large amounts of digestive enzymes. Which two organelles would you expect to be particularly well developed?
Rough ER and Golgi apparatus.
Bacteria do not have mitochondria, but some bacteria can still carry out aerobic respiration. How is this possible?
The proteins involved in aerobic respiration are located in the plasma membrane.
A pancreatic cell produces and secretes large amounts of protein. Which organelles would you expect it to contain in large numbers?
Ribosomes, rough ER, Golgi apparatus and mitochondria.
Ribosomes synthesize proteins; rough ER processes proteins entering the secretory pathway; the Golgi modifies, sorts and packages proteins; mitochondria provide ATP needed for these energy-demanding processes.
A cell is specialized for breaking down and recycling damaged cell components. Which organelle would you expect it to contain in large numbers?
Lysosomes.
Why is having a large surface-area-to-volume ratio advantageous for a cell?
It allows more efficient exchange of substances with the environment.
A student says: “Prokaryotes are structurally simple, so they cannot carry out complex metabolic reactions.” Is this statement correct? Explain.
No, the statement is incorrect.
Although prokaryotes lack membrane-bound organelles, they can still carry out many complex metabolic pathways. Structural simplicity does not mean that their metabolism is simple.
Explain why a cell containing a nucleus and mitochondria must be eukaryotic, while a cell containing only ribosomes and a plasma membrane could be either prokaryotic or eukaryotic.
The nucleus and mitochondria are membrane-bound organelles found in eukaryotic cells. Ribosomes and plasma membranes are found in both types of cells.
A cell is specialized for storing large amounts of water and maintaining pressure against its cell wall. Which structure would you expect to be particularly large?
The central vacuole. The central vacuole stores water and dissolved substances.