Chapter 1 Homework Problems
Palade, Porter, and Sjøstrand each develop techniques for fixing and sectioning biological tissue for electron microscopy (1952-1953). A) cytological B) biochemical C) genetic
cytological
Claude isolates the first mitochondrial fractions from rat liver (1940). (multiple answers) A) cytological B) biochemical C) genetic
cytological and biochemical
What was the limit of resolution Leeuwenhoek's microscope? A) 0.83 μm B) 8.3 μm C) 83 μm D) 830 μm
0.83 μm
Which of the following accurately details the relationship between wavelength of illumination, lens quality, magnification, and the limit of resolution for light microscopy? A) As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will decrease. B) As shorter wavelength illumination and better quality lenses are used, magnification will decrease and the limit of resolution will decrease. C) As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will increase. D) Magnification and limit of resolution are independent of wavelength of illumination and lens quality for light microscopy.
As shorter wavelength illumination and better quality lenses are used, magnification will increase and the limit of resolution will decrease.
For each pair of techniques listed, indicate whether its members belong to the cytological, biochemical, or genetic strand of cell biology. Biochemical strand: Light microscopy/electron microscopy Transmission electron microscopy/scanning electron microscopy Centrifugation/ultracentrifugation Chromatography/electrophoresis Sequencing of a genome/bioinformatics Nucleic acid hybridization/DNA sequencing
Centrifugation/ultracentrifugation and Chromatography/electrophoresis
Suggest one advantage that DNA sequencing has over nucleic acid hybridization. A) 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. B) DNA sequencing makes it possible to determine the order of individual nucleotides along a DNA strand. C) DNA sequencing makes it possible to determine the tertiary and quaternary structure of a DNA strand. D) DNA sequencing can assess whether there is enough sequence complementarity to allow two strands to adhere to one another under specified conditions.
DNA sequencing makes it possible to determine the order of individual nucleotides along a DNA strand.
For each pair of techniques listed, indicate whether its members belong to the cytological, biochemical, or genetic strand of cell biology. Cytological strand: Light microscopy/electron microscopy Transmission electron microscopy/scanning electron microscopy Centrifugation/ultracentrifugation Chromatography/electrophoresis Sequencing of a genome/bioinformatics Nucleic acid hybridization/DNA sequencing
Light microscopy/electron microscopy and Transmission electron microscopy/scanning electron microscopy
Which of the following does NOT accurately highlight limitations to using in vitro, in vivo, and in silico systems in applying the scientific method in cell biology? A) It is difficult to translate in vitro data to whole-organism biology. B) It is difficult to control variables when using in vivo systems. C) It is impossible to predict and estimate all necessary factors when programing an in silico experiment. D) None of the three systems (in vitro, in vivo, and in silico) can be used to design controlled experiments.
None of the three systems (in vitro, in vivo, and in silico) can be used to design controlled experiments.
What kind of pizza do you have to eat to know whether pepperoni is the reason of heartburn? (Select two that apply.) A) Pizza with pepperoni, anchovies, and onions. B) Pizza with anchovies and onions. C) Pizza without pepperoni, anchovies, and onions. D) Pizza with pepperoni and anchovies. E)Pizza with pepperoni and onions.
Pizza with pepperoni, anchovies, and onions and Pizza with anchovies and onions.
Define limit of resolution. A) 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. B) The limit of resolution of a microscope is the clearance distance between the closest surface of the cover glass and the objective front lens. C) 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. 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.
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.
Describe how you might begin an experimental process to determine whether the heartburn is due to the pizza. A) Eat other pizzas with different ingredients, but containing either pepperoni, or anchovies, or onions. B) Try to consume pizza on certain nights in different conditions. C) Try to keep track of your eating habits for a few weeks. D) Try to avoid eating pizza, but eat it's ingredients separately.
Try to consume pizza on certain nights in different conditions.
Which of the following model organisms contributed the most to connecting the genetic strand and the biochemical strand of modern cell biology through the use of genetic techniques and biochemical techniques to show molecules interacting in vivo? A) Mutants of Drosophila melanogaster allowed for the mapping of genetic traits to particular chromosomes. B) Yeast was used to isolate enzymes into a cell-free extract that could carry out fermentation. C)Pea plants illustrated the behavior of trait inheritance between generations. D) Yeast mutants and yeast two-hybrid systems allow for the characterization of genetic mutants and determination of how specific proteins interact within a living cell.
Yeast mutants and yeast two-hybrid systems allow for the characterization of genetic mutants and determination of how specific proteins interact within a living cell.
A scientific hypothesis is __________. A) a test in which only specific conditions are allowed to vary B) a theory that has been confirmed C) a testable explanation of a natural phenomenon D) the same as a theory
a testable explanation of a natural phenomenon
Radioisotopes have been important in the study of biochemical pathways because they __________. A) allow scientists to trace the fate of specific molecules B) provide an important energy source for all organisms C) are major natural components of all cells D) allow scientists to view individual molecules
allow scientists to trace the fate of specific molecules
Avery, MacLeod, and McCarty demonstrate that bacterial transformation is attributable to DNA, not protein (1944). A) cytological B) biochemical C) genetic
genetic
Haeckel postulates that the nucleus is responsible for heredity (1868). A) cytological B) biochemical C) genetic
genetic
Muller discovers that X-rays induce mutations (1927). A) cytological B) biochemical C) genetic
genetic
Beadle and Tatum formulate the one gene-one enzyme hypothesis (1940). (multiple answers) A) cytological B) biochemical C) genetic
genetic and biochemical
Which type of microscope can detect density differences and thereby see organelles in living cells? A)phase contrast B) SEM C) fluorescence D) TEM
phase contrast
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) 50-100 nm B) 100-200 nm C) 400-500 nm D) 200-350 nm
200-350 nm
What was the limit of resolution of Hooke's microscope? A) 0.83 μm B) 8.3 μm C) 83 μm D) 830 μm
8.3 μm
Which of the following statements does NOT correctly validate the three strands that compose modern cell biology? A) Cellular DNA contains information about the structure and function of cellular proteins. B) Mutations in the cellular DNA can compromise cellular and macromolecular structure and function. C) Cellular structure arises from the combined structures of the macromolecules that compose cells. D) All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.
All of the other available answer choices validate the relationships between the three strands that compose modern cell biology.
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 pizza of each kind (except pizza without ingredients) in at least three different days. B) Eat pizza of each kind (including pizza without ingredients) in at least three different days. C) Eat pizza in the morning instead of evening. D) Eat pizza without ingredients. E) Eat three pizzas at a time instead of one.
Eat pizza of each kind (including pizza without ingredients) in at least three different days.
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 video cameras to collect digital images for computer storage. C) Electron microscopy is capable of much greater limit of resolution and hence much less resolving power. D) Electron microscopy uses complex mathematical algorithms to increase the contrast and resolution of digital images.
Electron microscopy is capable of much greater resolution and hence much higher useful magnification.
Suggest one advantage that electrophoresis has over chromatography. A) Electrophoresis separates molecules based on differences in chemical properties, thereby making it possible to separate molecules that undergo similar chemical reactions. 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 solubility, thereby making it possible to separate molecules that are similar in mass and size. D) Electrophoresis separates molecules based on mass differences, thereby making it possible to separate molecules that are similar in molar mass.
Electrophoresis separates molecules based on charge differences, thereby making it possible to separate molecules that are similar in size, shape, and density.
Suggest one advantage that scanning electron microscopy has over transmission electron microscopy. A) Scanning electron microscopy makes it possible to only visualize cells and tissues as if in two dimensions. B) Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in three dimensions. C) Scanning electron microscopy makes it possible to only visualize cells and tissues as if in three dimensions. D) Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in two dimensions.
Scanning electron microscopy makes it possible to visualize subcellular structures and macromolecules as if in three dimensions.
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 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. D) 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.
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.
For each pair of techniques listed, indicate whether its members belong to the cytological, biochemical, or genetic strand of cell biology. Genetic strand: Light microscopy/electron microscopy Transmission electron microscopy/scanning electron microscopy Centrifugation/ultracentrifugation Chromatography/electrophoresis Sequencing of a genome/bioinformatics Nucleic acid hybridization/DNA sequencing
Sequencing of a genome/bioinformatics and Nucleic acid hybridization/DNA sequencing
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 mixtures containing charged molecules, whereas conventional centrifugation separates neutral biomolecules only. D) 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.
Ultracentrifugation is capable of much higher speeds and hence much greater centrifugal force than conventional centrifugation.
Which of the following is INCONSISTENT with the cellular basis of life? A) Cellular function is intimately linked to cellular structure. B) The nuclear and mitochondrial DNA of a cell contains all of the information necessary for cellular reproduction. C) All anatomical structures and physiological processes of an organism are consequences of emergent properties of cellular structures and cellular processes. D) Viruses are living, acellular parasites.
Viruses are living, acellular parasites.
Hoppe-Seyler isolates the protein hemoglobin in crystalline form (1864). A) cytological B) biochemical C) genetic
biochemical
Lehninger demonstrates that oxidative phosphorylation depends for its immediate energy source on the transport of electrons in the mitochondrion (1957). A) cytological B) biochemical C) genetic
biochemical
Lipmann postulates the central importance of ATP in cellular energy transactions (1940). A) cytological B) biochemical C) genetic
biochemical
Ostwald proves that enzymes are catalysts (1893). A) cytological B) biochemical C) genetic
biochemical
Davson and Danielli postulate a model for the structure of cell membranes (1935). A) cytological B) biochemical C) genetic
cytological
Kollicker describes "sarcosomes" (now called mitochondria) in muscle cells (1857). A) cytological B) biochemical C) genetic
cytological
