Unit 1 (Chapter 4, Test Yourself Questions) Flashcards
The cell theory states that
all living things are composed of cells.
cells are the smallest units of living organisms.
new cells come from pre-existing cells by cell division.
all of the above.
only a and b are true.
D
For a microscope, resolution refers to
the ratio between the size of the image produced by the microscope and the actual size of the object.
the degree to which a particular structure looks different from other structures around it.
how well a structure takes up certain dyes.
the ability to observe two adjacent objects as being distinct from each other.
the degree to which the image is magnified.
D
A spherical cell has a radius of 34 μm. What is its surface area/volume ratio?
- 088
- 12
- 3
- 7
127
Surface Area = (A=4pie(r)squared)
Volume = 4/3pie(r)cubed
a
If a motor protein was held in place and a cytoskeletal filament was free to move, what type of motion would occur when the motor protein was active?
The motor protein would “walk” along the filament.
The filament would move.
The filament would bend.
all of the above
Only b and c would happen
b
Each of the following is part of the endomembrane system except
the nuclear envelope.
the endoplasmic reticulum.
the Golgi apparatus.
lysosomes.
mitochondria.
e
Vesicle transport occurs between the ER and the Golgi in both directions. Let’s suppose a researcher exposed some cells to a drug that inhibited vesicle transport from the Golgi to the ER but did not affect vesicle transport from the ER to the Golgi. If you observed the cells microscopically after the drug was added, what would you expect to see happen over the course of 1 hour?
The ER would get smaller, and the Golgi would get larger.
The ER would get larger, and the Golgi would get smaller.
The ER and Golgi would stay the same size.
Both the ER and Golgi would get larger.
Both the ER and Golgi would get smaller.
a
Functions of the smooth endoplasmic reticulum include
detoxification of harmful organic molecules.
metabolism of carbohydrates.
protein sorting.
all of the above.
a and b only.
e
The central vacuole in many plant cells is important for
storage.
photosynthesis.
structural support.
all of the above.
a and c only.
e
Let’s suppose an abnormal protein contains three sorting signals: an ER signal sequence, an ER retention sequence, and a mitochondrial matrix-targeting sequence. The ER retention sequence is supposed to keep a protein within the ER. Where would you expect this abnormal protein to go? Note: Think carefully about the timing of events in protein sorting and which events occur cotranslationally and which occur post-translationally.
It would go to the ER.
It would go the mitochondria.
It would go to both the ER and mitochondria equally.
It would remain in the cytosol.
It would be secreted.
a
Which of the following observations would not be considered evidence for the endosymbiosis theory?
Mitochondria and chloroplasts have genomes that resemble smaller versions of bacterial genomes.
Mitochondria, chloroplasts, and bacteria all divide by binary fission.
Mitochondria, chloroplasts, and bacteria all have ribosomes.
Mitochondria, chloroplasts, and bacteria all have similar sizes and shapes.
All of the above are considered evidence for the theory.
c
Which of these is the study of individual cells and their interactions with each other?
Cell biology
The interaction of which of the following macromolecules plays an important role in the formation of living cells?
Multiple select question.
RNA
DNA
Lipids
Carbohydrates
Proteins
RNA
DNA
Proteins
Which hypothesis regarding the origin of life on Earth suggests that oxidation-reduction (redox) reactions may be responsible for the formation of complex organic molecules from simple organic molecules?
Extraterrestrial hypothesis
Reducing atmosphere hypothesis
Oxidizing hypothesis
Deep-sea vent hypothesis
Reducing atmosphere hypothesis
During the second stage in the origin of life, small organic molecules polymerized to form which of the following on the surface of clay?
Macromolecules
Which of the following statements are true of polymers inside the protobiont?
Multiple select question.
Lacked basic metabolic pathways
Lacked the ability to create new polymers
Had catalytic functions
Contained information
Had catalytic functions
Contained information
The field that involves the study of cells and how they interact with other cells is termed
Cell biology
Identify the functions exhibited by RNA that may have led to it being the first macromolecule.
Multiple select question.
Ability to store information
Ability to function as ribozymes
Ability to perform photosynthesis
Ability to self-replicate
Ability to form membranes
Ability to store information
Ability to function as ribozymes
Ability to self-replicate
Which macromolecule forms the foundation for the structure and activities of living cells?
Multiple choice question.
Protein
DNA
RNA
Protein
How would early cells benefit from DNA replacing RNA as the information storage molecule?
Multiple select question.
Information would be stored in a more stable molecule.
RNA would have more flexibility in its catalytic functions.
DNA mutates more easily.
RNA would serve a role only as mRNA.
Information would be stored in a more stable molecule.
RNA would have more flexibility in its catalytic functions.
The origin of life was likely preceded by a period in which small organic molecules accumulated on the surface of ______.
Multiple choice question.
rocks
clay
water
viruses
Clay
A magnification tool that enables researchers to study the structure and function of cells is the
.
Microscope
Protobionts, the likely precursors of living cells, acquired a(n) ______ that separated the internal contents of the protobiont from the external environment.
Multiple choice question.
nucleus
boundary
extracellular matrix
reticulum
Boundary
The resolution of this microscope is better than a light microscope:
Multiple choice question.
proton
specialty
electron
dark
Electron
The macromolecule ______ can self-replicate, store information, and perform catalytic functions and may likely have been the first macromolecule to evolve.
Multiple choice question.
protein
RNA
DNA
phospholipid
RNA
What are the two main types of electron microscopy?
Multiple select question.
Confocal fluorescence microscopy
Fluorescence electron microscopy
Phase contrast microscopy
Scanning electron microscopy
Transmission electron microscopy
Scanning electron microscopy
Transmission electron microscopy
The different chemical properties of amino acids have given proteins ______ catalytic ability than RNA molecules.
Multiple choice question.
greater
lesser
Greater
Which of these is an optical instrument that allows researchers to view and study very small objects, such as cellular structures?
Multiple choice question.
PET scan
Magnifying glass
Telescope
Microscope
Microscope
The complete set of genetic material present in a cell or organism is called its ______.
Multiple choice question.
phenotype
proteome
genotype
genome
gene
Genome
True or false: The resolution of an electron microscope is far better than that of a light microscope.
True false question.
True
False
True
Based on cell structure, all life forms can be placed into two categories called _______ and ___________.
Prokaryotic and eukaryotic
What do prokaryotes lack?
Ribsomes
Cytoplasm
Nucleus
Cell wall
Nucleus
Two general types of electron microscopy have been developed:
Transmission and scanning
Prokaryotes consist of two categories of organisms.
Bacteria and Archaea
How would early cells benefit from DNA replacing RNA as the information storage molecule?
Multiple select question.
RNA would have more flexibility in its catalytic functions.
DNA mutates more easily.
Information would be stored in a more stable molecule.
RNA would serve a role only as mRNA.
RNA would have more flexibility in its catalytic functions.
Information would be stored in a more stable molecule.
A phospholipid bilayer that forms a barrier between a cell and its external environment is the plasma ________
Membrane
The entire complement of the genetic material of a species is its _________
genome
Structures found in both prokaryotic and eukaryotic cells that are the sites of polypeptide synthesis are called ________
Ribosomes
Which of the following is the best reason for cells being small?
Multiple choice question.
Larger cells would not be able to get necessary gases and nutrients quickly enough.
The cell membrane can only stretch so much and so cannot accommodate the larger size.
Larger cells would create too much heat and enzymes will denature.
Larger cells would require more nutrients and there is usually a limited supply.
Larger cells would not be able to get necessary gases and nutrients quickly enough.
The region of a eukaryotic cell that is outside the membrane-bound organelles but inside the plasma membrane is the
Cytosol or cytoplasm
Where is most of the DNA located in a eukaryotic cell?
nucleus
What cells have membrane-bound organelles to compartmentalize functions?
Multiple choice question.
Neither prokaryotic nor eukaryotic cells
Prokaryotic cells only
Both prokaryotic and eukaryotic cells
Eukaryotic cells only
Eukaryotic cells only
What accelerates chemical reactions?
enzymes
List the three different types of protein filaments that make up the cytoskeleton.
Multiple select question.
Mesosomes
Intermediate filaments
Microtubules
Actin filaments
Enzyme filaments
Intermediate filaments
Microtubules
Actin filaments
The class of proteins that use ATP as a source of energy to promote various types of movements is called ? proteins.
Motor
Eukaryotic cells have many membrane-bound compartments called _____________
, whereas prokaryotic cells do not exhibit compartmentalization.
Organelles
In eukaryotes, the endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, nuclear envelope, and plasma membrane form a network of membranes called the _____________ .
Endomembrane system
The nucleus is enclosed by a double membrane structure called the ?
Nuclear envelope
Intermediate filaments and actin compose this cell structure:
Cytoskeleton
The endoplasmic reticulum (ER) is a network of ?
Flat membranes or cisternae
The processing (ie: modification), sorting and secretion of cellular molecules are carried out by an organelle in the cell called the ___________
Golgi apparatus or golgi complex
Acid hydrolases are found in which organelle?
Golgi apparatus
Mitochondria
Lysosomes
Endoplasmic reticulum
Peroxisomes
Lysosomes
Which of the following is NOT part of the endomembrane system?
Golgi apparatus
Mitochondrion
Endoplasmic reticulum
Nuclear envelope
Lysosomes
Mitochondrion
True or false: Vacuoles are prominent organelles in animal cells, and rarely found in plants cells.
False
The membranes of the endoplasmic reticulum form which of the following?
Ribosome subunits
Cylindrical tubules
Fluid-filled tubules
Cisternae
Fluid-filled tubules
Cisternae
What is the function of the lysosome?
Multiple choice question.
Breakdown of macromolecules
Synthesis of ATP
Storage of genetic information
Synthesis of proteins
Breakdown
Peroxisome enzymes perform a variety of functions including (answer all that apply)
fat metabolism
amino acid metabolism
detoxification
protein synthesis
fat metabolism
amino acid metabolism
detoxification
The function of a chloroplast is to capture the light energy necessary for the synthesis of which of the following organic molecules in the process of photosynthesis.
Multiple choice question.
Nucleic acids
Amino acids
Fatty acids
Glucose
Glucose
The membranes of the endoplasmic reticulum form which of the following?
Multiple select question.
Fluid-filled tubules
Cisternae
Ribosome subunits
Cylindrical tubules
Fluid-filled tubules
Cisternae
What are the semiautonomous organelles of eukaryotic cells?
Chloroplasts and mitochondrion
True or false: The theory of endosymbiosis suggests that all membrane-bound organelles originated from bacteria that took up residence within a primordial eukaryotic cell.
True false question.
True
False
False
The production of ATP takes place in which of the following organelles?
Multiple choice question.
Endoplasmic reticulum
Nucleus
Golgi apparatus
Mitochondria
Mitochondria
Proteins that are destined for the ER, Golgi, lysosome, plasma membrane or secretion are first directed to the ER. This is called ____________
sorting because the first step in the sorting process begins while the proteins are being synthesized.
cotranslational sorting
Which of these molecules keeps other proteins in an unfolded state so that they can be transported?
Multiple choice question.
Chaperone
Motor
Transport
Enzyme
Chaperone
From a systems biology approach, a system can be which of the following?
Cell
Organ
DNA
Metabolic Pathway
Enzyme
Cell
Organ
Metabolic pathway
Following protein synthesis, ______ sorting can route proteins to the nucleus, mitochondria, chloroplasts, and peroxisomes.
pre-translational
semitranslational
cotranslational
post-translational
post-translational
A polypeptide with an ER ______ sequence is directed to the ______ endoplasmic reticulum.
signal; rough
A eukaryotic cell can be viewed as a system with four interacting parts:
Cytosol, the nucleus, semiautonomous organelles, and the endomembrane system.
