On the following photos, label cilium, flagellum, nucleus, and pseudopod.

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A cell may allow a large or charged chemical to move across the cytoplasmic membrane, down the chemical’s electrical and chemical gradients, in a process called _________ .                   .

a. active transport

b. facilitated diffusion

c. endocytosis

d. pinocytosis

Describe (or draw) an example of diffusion down a concentration gradient.

Which cellular structure is important in classifying a bacterial species as Gram positive or Gram negative?

a. flagella

b. cell wall

c. cilia

d. glycocalyx

Match the structures with their descriptions following. A letter may be used more than once or not at all, and more than one letter may be correct for each blank.

  ____ Glycocalyx

  ____ Flagella

  ____ Axial filaments

 ____ Cilia

  ____ Fimbriae

  ____ Pili

  ____ Hami

A. Bristlelike projections found in quantities of 100 or more

B. Long whip

C. Responsible for conjugation

D. “Sweet cup” composed of polysaccharides and/or polypeptides

E. Numerous “grappling-hook” projections

F. Responsible for motility of spirochetes

G. Extensions not used for cell motility

H. Made of tubulin in eukaryotes

I. Made of flagellin in bacteria

Label the structures of the following prokaryotic and eukaryotic cells. With a single word or short phrase, explain the function of each structure.

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a. h.

b. i.

c. j.

d. k.

e. l.

f. m.

g. n.

o.

p.

q.

A Gram-negative cell is moving uric acid across the cytoplasmic membrane against its chemical gradient. Which of the following statements is true?

a. The exterior of the cell is probably electrically negative compared to the interior of the cell.

b. The acid probably moves by a passive means such as facilitated diffusion.

c. The acid moves by an active process such as active transport.

d. The movement of the acid requires phagocytosis.

How do archaeal flagella differ from bacterial flagella and eukaryotic flagella?

Contrast bacterial and eukaryotic cells by filling in the following table.

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Gram-positive bacteria  __________.

a. have a thick cell wall, which retains crystal violet dye

b. contain teichoic acids in their cell walls

c. appear purple after Gram staining

d. all of the above

Endospores ___________ .

a. are reproductive structures of some bacteria

b. occur in some archaea

c. can cause shock, fever, and inflammation

d. are dormant, resistant cells

What factors may prevent a molecule from moving across a cell membrane?

Inclusions have been found to contain ___________ .

a. DNA

b. sulfur globules

c. dipicolinic acid

d. tubulin

Compare and contrast three types of passive transport across a cell membrane.

Dipicolinic acid is an important component of __________ .

a. Gram-positive archaeal walls

b. cytoplasmic membranes in eukaryotes

c. endospores

d. Golgi bodies

Contrast the following active processes for transporting materials into or out of a cell: active transport, group translocation, endocytosis, exocytosis.

Contrast symports and antiports.

Describe the endosymbiotic theory. What evidence supports the theory? Which features of eukaryotic cells are not explained by the theory?

Label each type of flagellar arrangement.

a. __________ <IMAGE> b. __________ <IMAGE>

c. __________ <IMAGE> d. __________ <IMAGE>

Sketch, name, and describe three flagellar arrangements in bacteria.

Match the terms with their descriptions following. Only one description is intended for each term.

 ____ Ribosome

 ____ Cytoskeleton

 ____ Centriole

 ____ Nucleus

 ____ Mitochondrion

 ____ Chloroplast

 ____ ER

 ____ Golgi body

 ____ Peroxisome

A. Site of protein synthesis

B. Contains enzymes to neutralize hydrogen peroxide

C. Functions as the transport system within a eukaryotic cell

D. Allows contraction of the cell

E. Site of most DNA in eukaryotes

F. Contains microtubules in "9 + 0" arrangement

G. Light-harvesting organelle

H. Packages large molecules for export from a cell

I. Its internal membranes are sites for ATP production

A scientist who is studying passive movement of chemicals across the cytoplasmic membrane of Salmonella enterica serotype Typhi measures the rate at which two chemicals diffuse into a cell as a function of external concentration. The results are shown in the following figure. Chemical A diffuses into the cell more rapidly than does B at lower external concentrations, but the rate levels off as the external concentration increases. The rate of diffusion of chemical B continues to increase as the external concentration increases.

a. How can you explain the differences in the diffusion rates of chemicals A and B?

b. Why does the diffusion rate of chemical A taper off?

c. How could the cell increase the diffusion rate of chemical A?

d. How could the cell increase the diffusion rate of chemical B?

A "9 + 2" arrangement of microtubules is seen in  __________ .

a. archaeal flagella

b. bacterial flagella

c. eukaryotic flagella

d. all prokaryotic flagella

Define cytosol.

Which of the following is most associated with diffusion?

a. symports

b. antiports

c. carrier proteins

d. endocytosis

The term fluid mosaic has been used in describing the cytoplasmic membrane. How does each word of that phrase accurately describe our current understanding of a cell membrane?

Which of the following is not associated with prokaryotic organisms?

a. nucleoid

b. glycocalyx

c. cilia

d. circular DNA

Which of the following is true of Svedbergs?

a. They are not exact but are useful for comparisons.

b. They are abbreviated “sv.”

c. They are prokaryotic in nature but exhibit some eukaryotic characteristics.

d. They are an expression of sedimentation rate during high-speed centrifugation.

Which of the following statements is true?

a. The cell walls of bacteria are composed of peptidoglycan.

b. Peptidoglycan is a fatty acid.

c. Gram-positive bacterial walls have a relatively thin layer of peptidoglycan anchored to the cytoplasmic membrane by teichoic acids.

d. Peptidoglycan is found mainly in the cell walls of fungi, algae, and plants.

Compare bacterial cells and algal cells, giving at least four similarities and four differences.