Biology Chapter 3

Which of the following is NOT a cytoskeletal fiber in eukaryotic cells? A. macrotubules B. intermediate filaments C. microtubules D. microfilaments E. All of the above are cytoskeletal fibers.

A

What does the cell theory state?

All living things are made of cells and All cells come from existing cells

If a solute is moving through a phospholipid bilayer from an area of higher concentration to an area of lower concentration without the assistance of a protein, the manner of transport must be _______. A. active transport. B. facilitated diffusion. C. simple diffusion. D. any of the above, depending on the solute. E.Solutes cannot cross phospholipid bilayers.

C

Which organelle would cause the most damage to cytoskeletal fibers in the cytoplasm if its contents were to leak into the cytoplasm? A. smooth ER B. nucleus C. lysosome D. Golgi apparatus E. rough ER

C

You find a single-cell organism with a cell wall in the soil of a forest—can this organism be an animal? Which of the following facts would convince you that the organism is a bacterium and not a plant? A. The cell wall is made of cellulose. B. The DNA is contained in a nucleus. C. The cell wall is made of peptidoglycan. D. a and b E. b and c

C

Bacteria have _______ cells, defined by the _______. A. prokaryotic; presence of a cell wall B. eukaryotic; presence of organelles C. eukaryotic; absence of a cell wall D. prokaryotic; absence of organelles E. eukaryotic; absence of organelles

D

Insulin is a protein hormone secreted by certain pancreatic cells into the bloodstream. Which of the following organelles are involved in the synthesis and secretion of insulin? A. rough ER B. Golgi apparatus C. ribosomes D. all of the above E. a and c

D

Sugars are large, hydrophilic molecules that are important energy sources for cells. How can they enter cells from an environment with a very high concentration of sugar? A. by simple diffusion B. by osmosis C. by facilitated diffusion D. by active transport E. by using ribosomes

D

Which of the following statements best explains why bacteria are considered living organisms? A.They can cause disease. B. They are made up of biological macromolecules. C. They move around. D. They are made of cells. E. They contain organelles.

D

The two major components of cell membranes are _______ and _______. A. phospholipids; DNA B. DNA; proteins C. peptidoglycan; phospholipids D. peptidoglycan; proteins E. phospholipids; proteins

E

Which of the following is associated with eukaryotic cells but not with prokaryotic cells? A. cell membrane B. cell wall C. DNA D. ribosomes E. nucleus

E

Many foods—for example, bacon and salt cod—are preserved with high concentrations of salt. How can high concentrations of salt inhibit the growth of bacteria?

High salt is hypertonic and causes the bacteria to shrink because water leaves the bacterial cell.

Although both humans and bacteria have ribosomes, streptomycin—which blocks ribosome function—does not harm a human who ingests it. Why?

Human cells have ribosomes that do not bind streptomycin; only prokaryotic ribosomes are affected by this drug.

Some inherited syndromes, for example MERRF (myoclonic epilepsy with ragged red fibers), interfere with the function of mitochondria. From what you know about mitochondria, why do you think the muscles and the nervous system are the predominant tissues affected in MERRF?

Mitochondria are the most metabolically active and require the most energy

Which of the following statements is TRUE about prokaryotes and eukaryotes?

Prokaryotes are smaller and lack the internal compartments that eukaryotes have.

Which of the following accurately compares prokaryotic and eukaryotic cells?

Prokaryotic and eukaryotic cells contain the same form of genetic information. Prokaryotic and eukaryotic cells both contain ribosomes to effectively use their genetic information,

Water is moving across a membrane from solution A into solution B. What can you infer? A.Solution A must be pure water. B. Solution A must have a lower solute concentration than Solution B. C. Solution A must have a higher solute concentration than Solution B. D. Solution A and Solution B must have the same concentration of solutes. E. Solution B must be pure water.

Solution A must have a lower solute concentration than Solution B

Which of the following accurately describes why specific material uses a protein to cross the membrane?

The hydrophobic core of a membrane will only allow hydrophobic substances to cross without a membrane protein

Fungi are eukaryotic organisms. Scientists have found it more challenging to develop treatments for fungal infections (e.g., yeast infections, athlete's foot, and certain nail infections) than for bacterial infections. Why is this so?

The potential targets found in these cells closely resemble our own eukaryotic cells

Which of the following is associated with all cells?

cell membrane ribosomes DNA

Penicillin interferes with __________________, causing bacteria to die from ______________.

cell wall synthesis; swelling and rupturing of the cell

The "endosymbiotic hypothesis" is a concept that __________.

explains how eukaryotic cells might have evolved mitochondria and chloroplasts within their cells.

Which of the following combinations INCORRECTLY matches an organelle with its function?

lysosome: internal support; cell and organelle movement

Which of the following cellular components would not be a good target for an antibiotic?

phospholipids

Which of the following types of transport are most closely related in terms of the energy requirements for moving material across a membrane?

simple diffusion and facilitated diffusion

Gram-positive and Gram-negative bacteria are most commonly differentiated in the laboratory by __________.

whether or not a dye is trapped within the cells during the Gram staining procedure