BI 218 chapter 1
Genetic change followed by selection are the fundamentals of what process? DNA duplication Evolution Genetic drift Regeneration Reproduction
B
Another thing all cells have in common is the ability to divide. False True
False
Cells are either prokaryotic, eukaryotic, or archaeic. False True
False
In plant cells, a tough cell wall takes the place of a cytoskeleton. False True
False
Antibiotics tend to target features that are unique to bacterial cells and absent from eukaryotic cells such as our own. Which of the following would present a safe target for a new antibiotic? The cell wall The endoplasmic reticulum The intermediate filaments The nuclear envelope The plasma membrane
A
The largest single compartment in most cells is: the cytosol. the endoplasmic reticulum. the Golgi apparatus. the mitochondrial matrix. the nucleus.
A
What is the cell theory? All cells are formed by the growth and division of existing cells. All cells can be seen using a microscope. All cells contain DNA. All cells require a continual input of energy to sustain life. All cells resemble the chambers occupied by monks.
A
Which of the following are prokaryotes? Archaea and bacteria Archaea and protozoans Bacteria and fungi Monotremes and prototheria Viruses and microbes
A
Which of the following organelles is a small, irregularly shaped organelle in which intracellular digestion occurs? Lysosome Nucleosome Peroxisome The endoplasmic reticulum The Golgi apparatus
A
Which statement is NOT true of chloroplasts? Chloroplasts are present in essentially all eukaryotic cells and in certain photosynthetic bacteria. Chloroplasts are thought to have originated from bacteria. Chloroplasts contain their own DNA. Chloroplasts produce food molecules and generate oxygen. Each has an internal stack of membranes and is enclosed by two membranes.
A
Which statement is NOT true of mitochondria? Mitochondria are not present in plant cells. Mitochondria are thought to have originated from bacteria. Mitochondria contain their own DNA. Mitochondria generate chemical energy for the cell. Mitochondria have an inner and outer membrane.
A
Like the differentiated cells in an individual plant or animal, all bacteria have the same DNA. False True
False
One thing all cells have in common is an ability to colonize any environment on Earth. False True
False
The cytoskeleton is one of the few permanent fixtures in the cell. False True
False
Mitochondria are essentially the same in all eukaryotes, including plants, animals, and fungi. From this observation, it can be concluded that mitochondria were most likely acquired: by an ancestral eukaryotic cell and then replaced by chloroplasts in the line that led to plant cells. by an ancestral eukaryotic cell before the lines that led to animal cells, plant cells, and fungi diverged. by an ancestral prokaryote and then lost in the line that led to archaea. by an ancestral prokaryotic cell. from a free-living, photosynthetic bacterium.
B
Scientists were studying yeast cells in which a mutation inactivated a gene required for cell division. Without this gene—and the protein it encoded—these mutant yeast cells were unable to divide normally. But the scientists discovered that introducing a related protein from human cells could "rescue" these mutant yeast cells, allowing the cells to resume normal division. Based on this finding, the most likely conclusion is that: modern humans most likely obtained their cell-division proteins from ancient yeast. the proteins that control cell division in yeast and humans are functionally equivalent and have been conserved, almost unchanged, for more than a billion years. yeast and humans diverged from a common ancestor much more recently than previously thought, perhaps fewer than a million years ago. yeast cells most likely obtained their cell-division proteins from the cells of early humans. yeast cells require human proteins to divide.
B
What is the name of the process by which eukaryotic cells engulf material captured from an external medium? Cytokinesis Endocytosis Endomitosis Endosymbiosis Exocytosis
B
What role is NOT performed by the cytoskeleton? Controlling cell shape and cell movement Generating chemical energy for the cell Generating contraction in muscle cells Pulling duplicated chromosomes to opposite poles in dividing cells Transporting organelles and molecules from one place to another in the cytoplasm
B
Which of the following is a model plant used by scientists? A. artemisifolia A. thaliana C. elegans H. floresiensis S. cerevisiae
B
Which statement is NOT true of E. coli? E. coli can be grown in the laboratory. E. coli is a model eukaryote. E. coli is a small, rod-shaped cell. E. coli normally lives in the gut of humans and other vertebrates. E. coli stores genetic information in the form of DNA.
B
The DNA in the nucleus of eukaryotic cells is separated from the cytoplasm by the: cell wall. endoplasmic reticulum. nuclear envelope. nucleoplasm. plasma membrane.
C
What do eukaryotic cells have that prokaryotes lack? A cell wall A means of generating their own energy A nucleus and other internal organelles Nucleic acids Ribosomes
C
Which is not evidence for the endosymbiotic origins of mitochondria and chloroplasts? Mitochondria and chloroplasts are surrounded by a double membrane. Mitochondria and chloroplasts contain their own DNA. Mitochondria and chloroplasts have similar DNA. Mitochondria and chloroplasts reproduce by dividing in two. Mitochondria and chloroplasts resemble bacteria.
C
Which organelle's ancestor was likely engulfed by primitive eukaryotes to help the cell survive in an oxygen-rich atmosphere? Chloroplast Lysosome Mitochondrion Nucleus Peroxisome
C
Which statement is NOT true about the differences between liver cells and kidney cells in the same animal? The different cells are generated during the animal's development. The different cells express different genes. The different cells have different DNA. The different cells have different roles in the body. The different cells produce different proteins.
C
Which structure could NOT be seen using an electron microscope? An individual cell DNA Electron Plasma membrane Ribosomes
C
Which term describes genes (and gene products) related by a common ancestral gene? Analogous Familial Homologous Superfluous Vestigial
C
One drawback of electron microscopy is that it: can only be used to view atomic details in structures larger than a ribosome. can only be used to view samples that are sliced very thinly. cannot be used to view a whole cell or organism. cannot be used to view living cells. requires the use of fluorescent probes.
D
One drawback of light microscopy is that it: can only be used to view samples that are sliced very thinly. cannot be used to view a whole cell or organism. cannot be used to view living cells. cannot be used to view structures smaller than a bacterium. requires the use of fluorescent probes.
D
Which is NOT a function of proteins? To act as molecular motors To catalyze chemical reactions To encase certain viruses To encode genetic information To provide cells with structural support
D
Which of the following organelles is an irregular maze of interconnected spaces enclosed by a membrane and functions as the site where most cell membrane components, as well as materials destined for export from the cell, are made? Lysosome Peroxisome Ribosome The endoplasmic reticulum The Golgi apparatus
D
Which of these is NOT part of the cytoskeleton? Actin filaments Intermediate filaments Microtubules Plasma membrane
D
DNA contains nucleotide sequences that: (A) are seemingly dispensable. (B) code for functional RNA molecules. (C) code for proteins. (D) regulate gene activity. (E) All of the above
E
Early studies of Drosophila melanogaster showed that: chromosomes are made exclusively of protein. chromosomes exist in sets of three. DNA exists only in eukaryotic organisms. eukaryotes carry their genes in circular plasmids. genes are carried on chromosomes.
E
In what way are all cells alike? They are about a tenth of a millimeter in diameter. They are round in shape. They are surrounded by a tough outer coat made of protein. They require other cells to survive and reproduce. They store their genetic instructions in DNA
E
The study of which of these organisms has yielded insights into molecular mechanisms that are relevant to human cancer? (A) Bacteria (B) Mice (C) Worms (D) Yeast (E) All of the above (F) None of the above
E
What is NOT a reason scientists study yeast? It can be grown in the laboratory. It can reproduce as rapidly as bacteria. It carries out all the basic tasks a eukaryotic cell must perform. It is as closely related to animals as it is to plants. It lacks a nucleus so it is easy to genetically manipulate
E
What mediates the exchange of materials between the endoplasmic reticulum, Golgi apparatus, the lysosomes, and the outside of the cell? Diffusion Peroxisomes The cytosol The extracellular matrix Transport vesicles
E
Which of the following is a stack of flattened membrane-enclosed sacs, functioning in receiving and often chemically modifying the molecules made in the endoplasmic reticulum, and then directing them to the exterior of the cell or to various locations inside the cell? Lysosome Peroxisome Ribosome The endoplasmic reticulum The Golgi apparatus
E
Which of the following is frequently studied as a model vertebrate? Arabidopsis Didinium Drosophila Jellyfish Zebrafish
E
Which organism would be the most useful for studying how mutations that cause sudden death in young athletes can affect the development of the heart? Arabidopsis thaliana Caenorhabditis elegans Raphus cucullatus Saccharomyces cerevisiae Zebrafish
E
The genome of the bacterium E. coli contains 4.6 million (4.6 x 106) nucleotide pairs, whereas the human genome contains some 3200 x 106 nucleotide pairs. Based on these numbers, one can conclude that: (A) E. coli are unicellular, whereas humans are multicellular. (B) humans are a more complex life-form than E. coli. (C) human cells are larger than E. coli. (D) human cells have 700 times more genes than E. coli. (E) All of the above (F) None of the above
F
All cells require oxygen to live. T or F
False
An organism that can survive life in a hydrothermal vent at the bottom of the ocean can thrive anywhere. False True
False
At a molecular level, the members of the two domains of prokaryotes—the archaea and bacteria—differ as much from each other as either does from the eukaryotes. False True
True
Human cells are capable of surviving in a culture dish. False True
True
If two genes from different organisms have closely similar DNA sequences, it is highly probable that both genes descended from a common ancestral gene. False True
True