Ch. 1: Rocketmix


Terms in this set (...)

All cells require oxygen to live
In what way are all cells alike?
They store their genetic instructions in DNA.
Genetic change followed by selection are the fundamentals of what process?
Which statement is NOT true about the differences between liver cells and kidney cells in the same animal?
The different cells have different DNA.
Another thing all cells have in common is the ability to divide.
Which is NOT a function of proteins?
To encode genetic information
What is the cell theory?
All cells are formed by the growth and division of existing cells.
One drawback of electron microscopy is that it:
cannot be used to view living cells.
One drawback of light microscopy is that it:
cannot be used to view structures smaller than a bacterium.
Which structure could NOT be seen using an electron microscope?
What do eukaryotic cells have that prokaryotes lack?
A nucleus and other internal organelles
Which of the following are prokaryotes?
Archaea and bacteria
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.
Cells are either prokaryotic, eukaryotic, or archaeic.
One thing all cells have in common is an ability to colonize any environment on Earth.
Like the differentiated cells in an individual plant or animal, all bacteria have the same DNA.
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
Antibiotic resistance is a serious medical problem. Genes that confer resistance to antibiotics can be readily transferred from one bacterial species to another, and the cells that acquire these traits are better able to evade the effects of the drugs we rely on to treat these infections. One way to test bacteria for drug resistance is to spread a culture of the cells onto a growth medium in a Petri dish. The bacteria multiply and spread, forming a "lawn." Onto this lawn are placed small discs that contain a specific antibiotic. If the cells are sensitive to an antibiotic, a clear "halo" will form around the disc—an area in which no bacteria have grown.

The figure shows two Petri dishes, each containing bacteria isolated from a different patient. The discs contain three different antibiotics. Based on these data, which conclusion is correct?
Patient 2 can be treated effectively with any of the three antibiotics tested.
An organism that can survive life in a hydrothermal vent at the bottom of the ocean can thrive anywhere.
The DNA in the nucleus of eukaryotic cells is separated from the cytoplasm by the:
nuclear envelope
Which statement is NOT true of mitochondria?
Mitochondria are not present in plant cells.
Which statement is NOT true of chloroplasts?
Chloroplasts are present in essentially all eukaryotic cells and in certain photosynthetic bacteria.
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?
The endoplasmic reticulum
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?
The Golgi apparatus
Which of the following organelles is a small, irregularly shaped organelle in which intracellular digestion occurs?
What mediates the exchange of materials between the endoplasmic reticulum, Golgi apparatus, the lysosomes, and the outside of the cell?
Transport vesicles
What is the name of the process by which eukaryotic cells engulf material captured from an external medium?
The largest single compartment in most cells is:
the cytosol
Which of these is NOT part of the cytoskeleton?
Plasma membrane
What role is NOT performed by the cytoskeleton?
Generating chemical energy for the cell
In plant cells, a tough cell wall takes the place of a cytoskeleton.
Which organelle's ancestor was likely engulfed by primitive eukaryotes to help the cell survive in an oxygen-rich atmosphere?
Based on your knowledge of cell structure, this cell is devoting a great deal of its resources to which process?
Synthesizing proteins
Based on your knowledge of cell structure, this cell is devoting a great deal of resources to which process?
Secreting proteins
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 before the lines that led to animal cells, plant cells, and fungi diverged.
Which is not evidence for the endosymbiotic origins of mitochondria and chloroplasts?
Mitochondria and chloroplasts have similar DNA.
Which statement is NOT true of E. coli?
E. coli is a model eukaryote.
What is NOT a reason scientists study yeast?
It lacks a nucleus so it is easy to genetically manipulate.
Which of the following is a model plant used by scientists?
A. thaliana
Early studies of Drosophila melanogaster showed that:
genes are carried on chromosomes.
Which of the following is frequently studied as a model vertebrate?
Human cells are capable of surviving in a culture dish.
If two genes from different organisms have closely similar DNA sequences, it is highly probable that both genes descended from a common ancestral gene.
Which term describes genes (and gene products) related by a common ancestral gene?
DNA contains nucleotide sequences that:
(A) are seemingly dispensable.

(B) code for functional RNA molecules.

(C) code for proteins.

(D) regulate gene activity.
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?
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
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:
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.
Comparing the gene sequences of different organisms can reveal information about how closely related those organisms are and provide clues about when those organisms diverged from a common ancestor. The more similar the sequences of a gene—or its protein product—the more closely related the organisms. Shown here are the DNA sequences of a portion of a gene from a human, a gorilla, and an orangutan. A colored letter marks each point where the gorilla or orangutan sequence differs from that of humans. The boxes beneath the DNA sequences represent the amino acids of the encoded protein product; again, a colored box represents a change from the human protein. Reviewing these data, the most likely conclusion is that:
humans are more closely related to gorillas than to orangutans.
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

The figure shows a segment of the amino acid sequence of a protein that is involved in the control of cell division in human cells and in two types of yeast, S. pombe and S. cerevisiae. Each amino acid is represented by a single letter, and the amino acids that are identical are shaded in green. Based on these data, which is the most likely conclusion?
The proteins are likely to perform similar functions in all three organisms.
What type of cell is shown in this micrograph?