Chapter 3 Quiz 3

What does the cell theory state?

A. All living things are made of cells and those cells come from existing cells. All cells come from existing cells. All living things are made of cells. All living cells come from existing cells and those cells contain organelles. All cells contain organelles.

Which of the following statements best explains why bacteria are considered living organisms?

A. They are made of cells. They contain organelles. They are made up of biological macromolecules. They move around. They can cause disease.

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?

A. Fungi are eukaryotes, like humans, thus their cellular components are similar. The fungi closely resemble bacteria. Antibiotics are only effective against viruses. Antibiotics do not work on eukaryotic cells. Eukaryotic cells do not contain the complex number of organelles.

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?

A. High salt is hypertonic and causes the bacteria to shrink because water leaves the bacterial cell. High salt is hypertonic and causes the bacteria to swell and burst because water rushes into the cell. High salt is hypotonic and causes the bacteria to shrink because water leaves the bacterial cell. High salt is hypotonic and causes the bacteria to swell and burst because water rushes into the cell. High salt is hypertonic and causes the bacteria to shrink because salt enters the bacterial cell.

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

A. Human cells have ribosomes that do not bind streptomycin; only prokaryotic ribosomes are affected by this drug. Human cells have an extra lipid layer around their outsides, preventing streptomycin from entering them. Human cells have far more ribosomes than bacteria, so relatively few ribosomes are blocked by streptomycin. Human cells contain a cell wall that prevents streptomycin from getting into the cytoplasm. Human cells are much, much larger than bacteria cells, and antibiotics are diluted so much in the cytoplasm that they are ineffective.

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?

A. Mitochondria are the most metabolically active and require the most energy. Mitochondria are only found in these cell types. Mitochondria, similar to chloroplasts, require light energy to function. Mitochondria have their own DNA and ribosomes. Mitochondria have the largest role in digestion.

Which of these statements is TRUE about prokaryotes and eukaryotes?

A. Prokaryotes are smaller and lack the internal compartments that eukaryotes have. They are both about the same size and have similar internal structures. Prokaryotes have a nucleus, whereas eukaryotes do not. Both prokaryotes and eukaryotes have internal compartments enveloped in membranes. They are both about the same size and have different internal structures.

Which of the following accurately compares prokaryotic and eukaryotic cells?

A. Prokaryotic and eukaryotic cells both contain ribosomes to effectively use their genetic information. Only prokaryotic cells contain mitochondria. Prokaryotic cells have a cell wall and eukaryotic cells do not have a cell wall. Prokaryotic cells do not contain cytoplasm and eukaryotic cells do. Prokaryotic and eukaryotic cells contain different forms of genetic information.

Water is moving across a membrane from solution A into solution B. What can be inferred?

A. Solution A must have a lower solute concentration than Solution B. Solution A and Solution B must have the same concentration of solutes. Solution B must be pure water. Solution A must have a higher solute concentration than Solution B. Solution A must be pure water.

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 characteristics would indicate that the organism is a bacterium and not a plant?

A. The cell wall is made of peptidoglycan. The DNA is contained in a nucleus and the cell wall is made of peptidoglycan. The DNA is contained in a nucleus and the cell wall is made of cellulose. The DNA is contained in a nucleus. The cell wall is made of cellulose.

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

A. The hydrophobic core of a membrane will only allow hydrophobic (i.e., non-polar) substances to cross without a membrane protein. Material can only cross the membrane via a protein. The membrane will allow any substance to cross it if the concentration of solute is high enough on one side of the membrane. The hydrophilic core of a membrane will only allow hydrophilic (i.e., polar) substance to cross without a membrane protein. The membrane will allow any substance to cross it as long as it moves from a high concentration to low.

Which of these cellular components is(are) associated with all cells?

A. cell membrane, ribosomes, and DNA cell membrane and ribosomes ribosomes cell membrane DNA

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

A. cell wall synthesis; swelling and rupturing of the cell cell division; old age protein synthesis; an inability to make protein membrane synthesis; intact membranes osmosis; dehydration (a lack of internal water)

The "endosymbiotic hypothesis" is a concept that explains _____.

A. how eukaryotic cells might have evolved mitochondria and chloroplasts within their cells why mitochondria and chloroplasts are so unlike each other how plant cells produce usable cellular energy from sunlight why chromosomes are only found inside the nucleus of a eukaryotic cell why ribosomes are only found in the eukaryotic cytoplasm, never inside an organelle

Which organelle would cause the most damage to cytoskeletal fibers in the cytoplasm if its contents were to leak into the cytoplasm?

A. lysosome rough ER nucleus Golgi apparatus smooth ER

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

A. lysosome: internal support; cell and organelle movement endoplasmic reticulum: site of protein and lipid production chloroplast: conversion of sunlight energy to usable cellular energy mitochondrion: conversion of food to usable energy Golgi apparatus: protein processing and packaging

Which of the following is NOT a cytoskeletal fiber in eukaryotic cells?

A. macrotubules microfilaments lysosomes microtubules intermediate filaments

Which of the following is not found in prokaryotic cells?

A. mitochondria ribosomes cytoplasm cell membrane cell membrane and ribosomes

Which of the following is associated with eukaryotic cells but not with prokaryotic cells?

A. nucleus ribosome cell membrane cell wall DNA

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

A. phospholipids peptidoglycan ribosomes phospholipids and peptidoglycan peptidoglycan and ribosomes

The two major components of cell membranes are _______ and _______.

A. phospholipids; proteins phospholipids; DNA peptidoglycan; phospholipids peptidoglycan; proteins DNA; proteins

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. ribosomes, rough ER, and Golgi apparatus rough ER ribosomes rough ER and Golgi apparatus Golgi apparatus

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. simple diffusion facilitated diffusion Solutes cannot cross phospholipid bilayers. active transport Solutes may use active transport, facilitated diffusion, or simple diffusion, depending on the solute.

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

A. simple diffusion and facilitated diffusion simple diffusion and active transport Simple diffusion, facilitated diffusion, and active transport all have similar energy requirements active transport and facilitated transport Methods of moving material across a membrane do not require energy.

Sugars are large, hydrophilic molecules that are important energy sources for cells. Sugars can enter cells from an environment with a very high concentration of sugar by

A. Facilitated diffusion using ribosomes. simple diffusion. active transport. osmosis.