Bio Chapter 4
Which statement is NOT true about bacterial anatomy? A. The cell wall is located outside of the plasma membrane. B. The glycocalyx sheath is located inside the cell wall. C. There may be small rings of accessory DNA called plasmids. D. Bacteria may have fimbriae that help attach the bacteria to other structures.
B
_______ are to ribosomes as lipids are to _________. A. carbohydrates; rough endoplasmic reticulum B. nucleoli; lysosomes C. sugars; peroxisomes D. proteins; smooth endoplasmic reticulum
D
Cells that do NOT produce cell walls are:
animal cells
Which of these is NOT part of the endomembrane system of the cell? A. mitochondria B. endoplasmic reticulum C. lysosomes D. Golgi complex
A
Which statement is NOT true about bacteria? A. Bacteria contain membrane bound organelles. B. Some are photosynthetic. C. Some are motile due to flagella. D. All bacteria are prokaryotes. E. Bacteria have a cell wall that contains peptidoglycan.
A
Why is a large surface area: volume ratio needed for cells to function properly? A. Adequate surface area (plasma membrane) is needed to furnish nutrients to and expel wastes from the volume (cytoplasm). B. Smaller volumes reduce and larger surface areas reduce the cell's ability to bring nutrients in and get rid of waste. C. A smaller surface area allows the cell to increase its metabolic activity by bringing in even more nutrients than larger surface areas. D. The surface area and volume increase at the rate to ensure cell growth and reproduction.
A
According to the endosymbiotic theory, mitochondria and chloroplasts evolved from aerobic and photosynthetic bacteria that were engulfed and 'took up' residence in a host prokaryotic cell. Use your knowledge of how plant and animal cells differ to answer the following questions: A. Did the ancestral plant cell engulf both types of bacteria ? Cite evidence to justify your answer. B. Did the ancestral animal cell engulf both types of bacteria? What evidence can you cite to justify your answer. Cite evidence to justify your answer. C. If the answer to either A or B is yes, then which type of bacteria would have been engulfed first? Cite evidence to justify your answer.
A. Yes, the ancestral plant cell engulfed both types of bacteria. Plant cells contain both mitochondria and chloroplasts. B. No, the ancestral animal cell engulfed only the aerobic bacterium. Animal cells have mitochondria but no chloroplasts. C. The ancestral cell first engulfed an aerobic bacterium, then diverged into two cell lines, each having the evolving mitochondria. One line evolved into an animal cell, which only has mitochondria and not chloroplasts. The other cell then engulfed the photosynthetic bacteria and through time became plant cells, which contain mitochondria and chloroplasts.
Cell biologists have introduced radioactively labeled carbohydrates, fats and amino acids to living cells, allowed time for cell metabolism, and then disrupted the cells in a blender and separated out the various cell organelles from the cytoplasm. They found the radioactive molecules could soon be detected as part of various cellular compounds, although the visible cell structures appeared unchanged. This leads us to conclude that A. these "food" molecules are used only for energy. B. most cell components are constantly being broken down and rebuilt. C. radioactivity was transferred from the introduced molecules to the resident stable molecules. D. molecules diffuse at random through the cytoplasm and into cell organelles. E. radioactivity has an unusual role in metabolism of living cells.
B
Chloroplasts are to ____________ as ___________ are to aerobic respiration. A. stroma, cristae B. photosynthesis, mitochondria C. thylakoid membranes, matrix D. protein synthesis, lysosomes
B
Each time the water in a cell freezes slowly, long sharp crystals spear through the membrane structures of the cell. However, in the frozen state, virtually no chemical reactions occur. The most likely explanation for the bad taste of meat that has "freezer burn" from repeated freezing is the destruction of A. the Golgi bodies and their vesicles. B. lysosomes and resultant autodigestion. C. rough endoplasmic reticulum causing the release of ribosomes. D. ribosomes causing them to break into subunits. E. the nuclear membrane causing mixing of nucleoplasm and cytoplasm.
B
From your knowledge of the size and density of cell components and the process of centrifugation, predict the order (from first to last) that the nucleus and organelles will be extracted? A. ribosomes-mitochondria and chloroplasts-nucleus-soluble cytoplasm B. nucleus-mitochondria and chloroplasts-ribosomes-soluble cytoplasm C. nucleus-mitochondria and chloroplasts-soluble cytoplasm-ribosomes D. mitochondria and chloroplasts-nucleus-soluble cytoplasm-ribosomes E. soluble cytoplasm-ribosomes-mitochondria and chloroplasts-nucleus
B
Most bacteria live in a solution that is hypotonic relative to the cytoplasm of the bacteria. The cell wall of a bacterium is a peptidoglycan polymer that is tightly cross-linked. This would therefore function to A. regulate the flow of most molecules into and out of the bacterial cell. B. provide a rigid wall that prevents the cell from swelling. C. provide a rigid wall that prevents the cell from shrinking. D. confirm a close relationship to plant cells that have a similar structure and live in hypotonic solutions. E. make all bacteria fairly uniform in metabolic chemistry.
B
Without a cytoskeleton, eukaryotic cells would NOT A. synthesize protein. B. have an efficient way to transport materials from one organelle to another. C. have an efficient means of metabolism. D. communicate with adjacent cells.
B
As they flow over rotten logs as a fluid sheet, slime molds appear to lack any partitioning into cell units; however, slime molds do become cellular when they change form to produce spores. The surface of some parasitic flatworms and some insect tissues are a "syncytium" or layer of living material that contains many nuclei and cell organelles but lacks partitioning by cell membranes. These tissues consume food and produce wastes. In light of the cell theory that "all living things are composed of cells," then A. these tissues are not living because they are not cellular. B. these tissues are obviously a bridge between nonliving and primitive living cells. C. the general concept of life-is-cellular still holds because these organisms are cellular at specific stages in their life cycle, but this shows that cell membrane partitions can be abandoned. D. this proves that a "vital force" beyond cell chemistry can give life to substances. E. All of the choices are true.
C
Of the following, which is NOT associated with the mitochondria? A. ATP production B. cristae C. stroma D. matrix
C
The springtail is a very common small insect that lives in rotten logs, rich soil, and other humid places. Its cuticle is water repelling (hydrophobic) except for a strange organ, the collophore, on its ventral side. Because it lacks the excretory organs of other insects, the springtail has this organ in contact with the water (it is responsible for ion balance and secretion of wastes). If we examined the cell structure of this collophore, we would expect to find a high number of A. nuclei. B. ribosomes. C. Golgi bodies. D. lysosomes. E. centrioles.
C
Which cytoskeletal element is NOT correctly associated with its characteristic? A. Cilia are small extensions of membrane-surrounded microtubules. B. Microtubules are made up of a globular protein called tubulin. C. Centrioles are found in the microtubule organizing centers of plants. D. Flagella have a 9 + 2 pattern of microtubule structure. E. Basal bodies are located at the base of cilia and flagella.
C
Which is NOT a characteristic of mitochondria? A. A mitochondrion has two membranes. B. Mitochondria are the site of cellular respiration. C. Mitochondria are found in prokaryotic and eukaryotic cells. D. Mitochondria contain DNA and ribosomes. E. The inner space of the mitochondrion contains a fluid matrix.
C
Which is NOT true of eukaryotic cells? A. A true nucleus contains the chromosomes. B. Eukaryotic cells contain membrane-bounded compartments. C. They contain ribosomes that are smaller than those of prokaryotic cells. D. They all contain mitochondria. E. They contain many organelles in the cytoplasm.
C
Which is a true statement about ribosomes? A. Ribosomes contain DNA and protein. B. Ribosomes are active in carbohydrate synthesis. C. Ribosomal subunits leave the nucleus after being formed by the nucleolus. D. Polyribosomes are the subunits of ribosomes. E. Ribosomes are only found associated with the endoplasmic reticulum in prokaryotic cells.
C
Which of the following gives rise to both lysosomes and vesicles? A. rough endoplasmic reticulum B. mitochondria C. Golgi apparatus D. ribosomes
C
Which of the following gives rise to both lysosomes and vesicles? A. rough endoplasmic reticula B. mitochondria C. Golgi apparati D. ribosomes
C
Which of the following is NOT offered as evidence in support of the endosymbiotic theory, the belief that a eukaryotic cell has evolved as a "committee" of prokaryotic cells? A. Mitochondria and chloroplasts are similar in size and structure to some species of bacteria. B. The ribosomes of chloroplasts and mitochondria are similar to bacteria. C. Mitochondria and chloroplasts can actively break away from eukaryotic cells and live on their own. D. Mitochondria and chloroplasts have their own DNA coding separate from the eukaryotic nucleus. E. All of the choices offer support of the endosymbiotic theory.
C
All cells have these two characteristics: A. contain DNA in the nucleus and have a plasma membrane B. produce a cell wall outside of the plasma membrane C. contain mitochondria and chloroplasts D. have a plasma membrane and ribosomes in the cytoplasm
D
An amino sugar called N-acetylmuramic acid is an important building block of the cell wall of some bacteria. Penicillin prevents this amino sugar from being incorporated into the bacterial cell wall. Therefore, A. penicillin affects bacteria but not eukaryotes because eukaryotic cell walls are different. B. bacterial cells that had already formed their cell walls would be unaffected. C. penicillin would stop the growth of active colonies of susceptible bacteria. D. All of the choices are correct.
D
The cells that line our respiratory tract, and one-celled paramecia both have these short hair-like projections. A. flagella B. microfilaments C. centrioles D. cilia E. pili
D
The plant cell's central vacuole A. provides the plant cell with support. B. stores nutrients and cellular waste products. C. is a reservoir for water. D. All of the choices are correct.
D
Which is NOT true about the cell theory? A. Its various parts were described by Schleiden, Schwann, and Virchow. B. It states that all organisms are composed of cells. C. It states that all cells come from preexisting cells. D. It states that bacteria and other small organisms can arise spontaneously. E. It is accepted today by biologists as applying to virtually all forms of life.
D
Which of the following help direct the movement of materials or organelles throughout the cell? A. rough endoplasmic reticulum B. cytoskeleton C. smooth endoplasmic reticulum D. all of the choices are true
D
Which of the following organelles is found within a cell that is both eukaryotic and autotrophic? A. lysosomes B. ribosomes C. rough endoplasmic reticulum D. chloroplast
D
Membrane-bounded vesicles that contain enzymes for oxidizing small organic molecules with the formation of hydrogen peroxide are A. vacuoles. B. vesicles. C. glyoxisomes. D. lysosomes. E. peroxisomes.
E
All cells have a cell wall that regulates the passage of molecules into and out of the cell.
False
Mitochondria have an inner membrane system called thylakoid membranes.
False
After being formed by the ribosomes located on the endoplasmic reticulum, what is the next organelle to which a protein could be transported?
Golgi apparatus
You are a scientist who wants to produce large amounts of the protein insulin that is used to facilitate the entry of glucose into cells. You know that insulin genes may be introduced into bacteria by way of a plasmid vector. These bacteria may then be used as 'micro-manufacturers' of insulin. Your laboratory technicians explore various methods of producing the desired bacteria, but you are not sure how many and which of the bacterial cells have been transfected (have the plasmid with the insulin gene). Propose a way to determine which bacterial cells have been transfected with the engineered plasmid and are able to produce insulin.
One way of determining if the process has been successful is to add (ligate) the gene that confers antibiotic resistance to the insulin gene you are inserting into the plasmid. Now every plasmid that contains the insulin gene (your target gene) will not be killed by antibiotics. After you introduce the engineered plasmids (the one with the target gene -insulin- and the antibiotic resistant marker) into your bacterial cells, you incubate them in a nutrient broth that also contains antibiotic (usually ampicillin). Any cells that were not transfected (that do not have your target gene in them) are killed by the antibiotic. The ones that do have the gene also have the antibiotic resistant gene, and therefore survive the selection process. You now know which bacteria have the insulin genes.
What organelle would be found in increased quantities in the liver cells of a person who abuses alcohol and/ or other drugs on a regular basis?
The smooth endoplasmic reticulum is associated with detoxification, and would, therefore, be found in increased quantities of an alcohol or drug abuser.
Mitochondria and chloroplasts are able to reproduce independently from the division of the cell.
True
Mitochondria are thought to be derived from aerobic bacteria that became part of the eukaryotic cell through endosymbiosis.
True
A microscope that uses antibodies that glow to reveal the location of a protein in a cell is the
immunofluorescence microscope
A microscope used to observe living cells and organelles by contrasting the phase differences so that some regions appear brighter is the
phase contrast light microscope
A high-powered microscope that produces an image from scattered secondary electrons is the
scanning electron microscope (SEM)