a. They have no nucleus and hence no DNA.
b. They have no Golgi apparatus
c. They include bacteria, yeast, and protists.
d. They are all able to live on inorganic energy sources.
e. Both (a) and (b) are true of prokaryotic cells. 2. Which one of the following model organisms is favoured by plant molecular biologists for its small genome? a. Arabidopsis thaliana
b. Caenorhabditis elegans
c. Escherichia coli
d. Danio rerio
e. Drosophila melanogaster 3. Which one of the following statements regarding the cytoskeleton is false?
a. It is made up of microfilaments, microtubules and intermediate filaments.
b. It is involved in cell movement and thus is absent from plant cells.
c. It provides support to the plasma membrane.
d. It is dynamic and is constantly being rearranged.
e. It is not present in prokaryotic cells. 4. The cell sketched at right is most likely:
a. A prokaryotic cell
b. A protist
c. A plant cell
d. An animal cell
e. Either a protist or an animal cell; it is impossible to distinguish between these possibilities on the basis of the schematic pictured at right. 5. Which one of the following statements about the evolution of present‐day organisms is true?
a. Eukaryotes preceded prokaryotes.
b. Eukaryotes acquired chloroplasts before they acquired mitochondria.
c. The common ancestral cell was likely an archaean.
d. All of a, b, and c are true of the evolution of present‐day organisms.
e. None of a, b or c is true of the evolution of present‐day organisms.
6. Order the following in size from smallest to largest:
a. Protein molecule
c. Carbon atom _____ < _____ < _____ < _____ < _____
d. Endoplasmic reticulum
e. Yeast cell 7. The endosymbiont theory…
a. Is supported by the fossil record, which indicates that eukaryotic cells evolved before prokaryotic cells.
b. Suggests that mitochondria may have originated as photosynthetic bacteria and chloroplasts as aerobic bacteria that established stable, symbiotic relationships with a prokaryotic host cell.
c. Is supported by similarities between mitochondria/chloroplasts and protists, including the use of binary fission for reproduction, and the presence of genetic material in the form of a single, circular chromosome of DNA that lacks protein.
d. Is supported by the observation that some animals, such as the sea slug Elysia chlorotica, are able to acquire chloroplasts that are incorporated into and function within the animal’s cells, a phenomenon termed kleptoplasty. 8. The third tenet of the cell theory, that cells can arise only by division from a pre‐existing cell, is attributed to:
a. Schleidan & Schwann
b. Gorter & Grendel
c. Singer & Nicolson
e. Crick & Watson 9. Which one of the following statements about limitations on cell size is not correct?
a. Compartmentalization of the intracellular environment is a strategy used by eukaryotic cells to achieve larger cell sizes because it restricts the need for adequate concentrations of substrates to a specific region of the cell rather than the entire cell volume.
b. As cell size increases, the surface area available for exchange of nutrients and waste products does not keep up with the requirements of the cell, which are determined by its volume.
c. An internal transport system based on motor protein movement along the…