Chapter One, Mastering Biology 206

Which of the following statements is false? A. All cells have a membrane-bound nucleus B. All organisms consist of one or more cells C. Cells come in a wide variety of sizes and shapes D. The cell is the basic unit of structure for all organisms E. All cells arise from preexisting cells.

A. All cells have a membrane-bound nucleus

Which type of microscope can detect density differences and thereby see organelles in living cells? A. phase contrast B. fluorescence C. TEM D. SEM

A. phase contrast

Which type of microscopy has the greatest resolving power? A. confocal scanning microscopy B. electron microscopy C. digital video microscopy D. fluorescence microscopy E. phase-contrast microscopy

B. electron microscopy

Biochemical Strand

Centrifugation/ultracentrifugation and Chromatography/electrophoresis

Approximately how many liver cells would fit inside a palisade cell?

2.62liver cell(s)

Approximately how many bacterial cells would fit in the internal volume of a human liver cell?

2700 bacterial cell(s)

Suggest one advantage that the electron microscopy has over the light microscopy. A.Electron microscopy is capable of much greater resolution and hence much higher useful magnification. B. Electron microscopy uses complex mathematical algorithms to increase the contrast and resolution of digital images. C. Electron microscopy uses video cameras to collect digital images for computer storage. D. Electron microscopy is capable of much greater limit of resolution and hence much less resolving power.

A.Electron microscopy is capable of much greater resolution and hence much higher useful magnification.

Calculate the approximate volume of bacterial cell in cubic micrometers. (Recall that V=πr2hV=πr2h for a cylinder and that V=4πr3/3V=4πr3/3 for a sphere.)

Volume= 1.57 μm^3

Calculate the approximate volume of palisade cell in cubic micrometers. (Recall that V=πr2hV=πr2h for a cylinder and that V=4πr3/3V=4πr3/3 for a sphere.)

Volume= 11000 μm^3

Calculate the approximate volume of liver cell in cubic micrometers. (Recall that V=πr2hV=πr2h for a cylinder and that V=4πr3/3V=4πr3/3 for a sphere.)

Volume= 4200 μm^3

What was the limit of resolution Leeuwenhoek's microscope? A. 0.83 μm B. 8.3 μm C. 83 μm D. 830 μm

A. 0.83 μm

What are the approximate dimensions of the smallest structure that a contemporary cell biologist should be able to observe with a modern light microscope? A. 200-350 nm B. 400-500 nm C. 100-200 nm D. 50-100 nm

A. 200-350 nm

Suggest one advantage that DNA sequencing has over nucleic acid hybridization. A. DNA sequencing makes it possible to determine the order of individual nucleotides along a DNA strand. B. DNA sequencing makes it possible to identify species present in a sample of water, sewage, dirt, debris filtered from the air, or swab samples of organisms. C. DNA sequencing can assess whether there is enough sequence complementarity to allow two strands to adhere to one another under specified conditions. D. DNA sequencing makes it possible to determine the tertiary and quaternary structure of a DNA strand.

A. DNA sequencing makes it possible to determine the order of individual nucleotides along a DNA strand.

Which of the following is closest to a micrometer in size? A. a typical prokaryotic cell B. the width of a strand of DNA C. the length of a plant cell D. the length of a chicken egg E. the size of a ribosome

A. a typical prokaryotic cell

Radioisotopes have been important in the study of biochemical pathways because they __________. A. allow scientists to trace the fate of specific molecules B. allow scientists to view individual molecules C. are major natural components of all cells D. provide an important energy source for all organisms

A. allow scientists to trace the fate of specific molecules

Which of the following is the smallest? A. protein B. ribosome C. virus D. mitochondrion E. prokaryote

A. protein

You are studying the response of macrophages infected with the intracellular bacterium Brucella, specifically by examining which gene products are being expressed. You would be studying the macrophage ________ to obtain this information. A. transciptome B. amplicon C. genome D. metabolome E. proteome

A. transciptome

Which structures would Hooke have been able to see?

Animal and Plant Cells

What structures would Leeuwenhoek have been able to see?

Animal, Plant, and Bacterial cells.

What was the limit of resolution of Hooke's microscope? A. 0.83 μm B. 8.3 μm C. 83 μm D. 830 μm

B 8.3 μm

The Latin phrase omnis cellula e cellula refers to a cellular principle. Which of the following statements is the best interpretation of this phrase? A. Tissues are composed of similar cells B. All cells arise only from preexisting cells C. Organs are composed of tissues and cells D. Cells generally are found in clusters E. The cell is the basic unit of structure.

B. All cells arise only from preexisting cells

Suggest one advantage that electrophoresis has over chromatography. A. Suggest one advantage that electrophoresis has over chromatography. Electrophoresis separates molecules based on mass differences, thereby making it possible to separate molecules that are similar in molar mass. B. Electrophoresis separates molecules based on charge differences, thereby making it possible to separate molecules that are similar in size, shape, and density. C. Electrophoresis separates molecules based on differences in chemical properties, thereby making it possible to separate molecules that undergo similar chemical reactions. D. Electrophoresis separates molecules based on differences in solubility, thereby making it possible to separate molecules that are similar in mass and size

B. Electrophoresis separates molecules based on charge differences, thereby making it possible to separate molecules that are similar in size, shape, and density.

Define limit of resolution. A. The limit of resolution of a microscope is the clearance distance between the closest surface of the cover glass and the objective front lens. B. The limit of resolution of a microscope is a measure of how close together two points can be and still be distinguished from one another when viewed through the microscope. C. The limit of resolution of a microscope is the minimum distance or angular separation between two point objects which allows them to be resolved according to the Rayleigh criterion. D. The limit of resolution of a microscope is the shortest distance between four separate points in a microscopes field of view that can still be distinguished as distinct entities.

B. The limit of resolution of a microscope is a measure of how close together two points can be and still be distinguished from one another when viewed through the microscope.

Suggest one advantage that ultracentrifugation has over centrifugation. A.Ultracentrifugation allows to separate biomolecules with different physical properties, whereas conventional centrifugation precipitates all the biomolecules B. Ultracentrifugation is capable of much higher speeds and hence much greater centrifugal force than conventional centrifugation. C. Ultracentrifugation allows to separate biomolecules based on their size, shape, and/or density, whereas separation in a conventional centrifugation is based on molecular mass only. D. Ultracentrifugation allows to separate mixtures containing charged molecules, whereas conventional centrifugation separates neutral biomolecules only.

B. Ultracentrifugation is capable of much higher speeds and hence much greater centrifugal force than conventional centrifugation.

Although the scientific method may sound rather foreign when described in formal terms, you probably use the scientific method frequently without even realizing it. Suppose, for example, that recently you often have heartburn. You realize that the heartburn is most likely to occur on nights after you have eaten your favorite pizza, with pepperoni, anchovies, and onions. You wonder if the heartburn is caused by eating pizza and, if so, which of the ingredients might be the culprit. Part C. Now you should do the similar experiments with other ingredients. On the basis of the data obtained you can make a conclusion about the impact of each component. What experiments should you do to prove your results? A. Eat three pizzas at a time instead of one B. Eat pizza in the morning instead of evening C. Eat pizza of each kind (including pizza without ingredients) in at least three different days D. Eat pizza without ingredients E. Eat pizza of each kind (except pizza without ingredients) in at least three different days.

C. Eat pizza of each kind (including pizza without ingredients) in at least three different days

Suggest one advantage that bioinformatics has over sequencing of a genome. A. Sequencing of a genome uses computer analysis to aid in understanding and interpreting those data in terms of gene numbers and expression, whereas bioinformatics simply provides a large amount of data about the DNA present in the genome. B. Sequencing of a genome simply provides a large amount of data about the DNA present in the genome, whereas bioinformatics techniques such as image and signal processing allow extraction of useful results from small amounts of raw data. C. Sequencing of a genome simply provides a large amount of data about the DNA present in the genome, whereas bioinformatics uses computer analysis to aid in understanding and interpreting those data in terms of gene numbers and expression. D. Sequencing of a genome simply provides a large amount of data about the DNA present on a chromome, whereas bioinformatics provides a large amount of data about the DNA present in the entire genome.

C. Sequencing of a genome simply provides a large amount of data about the DNA present in the genome, whereas bioinformatics uses computer analysis to aid in understanding and interpreting those data in terms of gene numbers and expression.

Which of the following biochemical techniques uses an electrical field to separate macromolecules based on their mobility through a semisolid gel? A. light microscopy B. mass spectrometry C. electrophoresis D. chromatography E. ultracentrifugation.

C. electrophoresis

Which of the following statements do not correctly validate the three strands that compose modern biology? A. Cellular structure arises from the combined structures of the macromolecules that compose cells. B.Mutations in the cellular DNA can compromise cellular and macromolecular structure and function. C. Cellular DNA contains information about the structure and function of cellular proteins. D. All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.

D. All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.

Although the scientific method may sound rather foreign when described in formal terms, you probably use the scientific method frequently without even realizing it. Suppose, for example, that recently you often have heartburn. You realize that the heartburn is most likely to occur on nights after you have eaten your favorite pizza, with pepperoni, anchovies, and onions. You wonder if the heartburn is caused by eating pizza and, if so, which of the ingredients might be the culprit. Part B. What kind of pizza do you have to eat to know whether pepperoni is the reason of heartburn? A. Pizza without pepperoni, anchovies, and onions B. Pizza with pepperoni and anchovies C. Pizza with pepperoni and onions D. Pizza with anchovies and onions. E. Pizza with pepperoni, anchovies, and onions.

D. Pizza with anchovies and onions E. Pizza with pepperoni, anchovies, and onions

Although the scientific method may sound rather foreign when described in formal terms, you probably use the scientific method frequently without even realizing it. Suppose, for example, that recently you often have heartburn. You realize that the heartburn is most likely to occur on nights after you have eaten your favorite pizza, with pepperoni, anchovies, and onions. You wonder if the heartburn is caused by eating pizza and, if so, which of the ingredients might be the culprit. Part A. Describe how you might begin an experimental process to determine whether the heartburn is due to the pizza. A. Try to keep track of your eating habits for a few weeks B. Eat other pizzas with different ingredients, but containing either pepperoni, or anchovies, or onions C. Try to avoid eating pizza, but eat it's ingredients separately D. Try to consume pizza on certain nights in different conditions

D. Try to consume pizza on certain nights in different conditions

Which of the following is INCONSISTENT with the cellular basis of life? A. Cellular function is intimately linked to cellular structure. B. All anatomical structures and physiological processes of an organism are consequences of emergent properties of cellular structures and cellular processes. C. The nuclear and mitochondrial DNA of a cell contains all of the information necessary for cellular reproduction. D. Viruses are living, acellular parasites.

D. Viruses are living, acellular parasites.

Melvin Calvin and his colleagues used which of the following to deduce the steps in the Calvin cycle? A. electron microscopy B. ultracentrifugation C. negative staining D. radioisotopes E. Drosophila melanogaster

D. radioisotopes

Wohler revolutionized biology through his demonstration that biological molecules are governed by the ordinary laws of physics and chemistry. He demonstrated this principle by A. defining the laws of heredity B. inventing mass spectrometry which is commonly used to determine the size and composition of individual proteins C. discovering active agents in cell extracts that were specific biological catalysts that have since come to be called enzymes D. synthesizing urea in the laboratory from ammonium cyanate E. developing techniques for isolating, purifying, and analyzing subcomponents of cells.

D. synthesizing urea in the laboratory from ammonium cyanate

You wish to obtain a purified sample of mitochondria from lysed cells. The best way to obtain this sample would be A. polyacrylamide gel electrophoresis B. both centrifugation and polyacrylamide gel electrophoresis C. agarose gel electrophoresis D. chromatography E. centrifugation

E. centrifugation

You are working on a project that involves the direct observation of DNA molecules. The microscope that would give you the best information at this time would be the A. digital video microscope B. phase-contrast microscope C. light microscope D. fluorescent microscope E. transmission electron microscope

E. transmission electron microscope

Cytological strand

Light microscopy/electron microscopy and Transmission electron microscopy/scanning electron microscopy

Suggest one advantage that scanning electron microscopy has over transmission electron microscopy. A. Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in two dimensions. B. Scanning electron microscopy makes it possible to only visualize cells and tissues as if in two dimensions. C. Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in three dimensions. D. Scanning electron microscopy makes it possible to only visualize cells and tissues as if in three dimensions.

Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in three dimensions.

Genetic Strand

Sequencing of a genome/bioinformatics and Nucleic acid hybridization/DNA sequencing

Would Hooke have been able to see any of the structures shown in the figure below?

Yes, he would.

Would Leeuwenhoek have been able to see any of the structures shown in the figure below?

Yes, he would.