BIOL150 Lecture 7: biol 150 Lecture 7: biol 130 Lecture 7: Unit 7- Intracellular Transport
Get access
Related Documents
Related Questions
The endosymbiont theory suggests that mitochondria and chloroplasts evolved from ancient bacteria that were ingested by primitive nucleated cells. Biologists have proposed that endosymbiosis led to the evolution of other cellular structures, such as flagella and peroxisomes, as well. Over hundreds of millions of years, the ingested bacteria lost features not essential for survival inside the host cell.
Part B
Explain your reasoning.
Drag the terms on the left to the appropriate blanks on the right to complete the sentences.
phagocytosis pinocytosis phagocytic pinocytic invaginations protrusions An identical arrangement of membranes follows _: the ingested bacterium is surrounded by the membrane of the _ vacuole. The thylakoid membrane systems found in chloroplasts may also be derived from ingested bacteria, because thylakoids form from _ of the inner membrane that pinch off to generate a separate membrane system. Part E Peroxisomes, unlike mitochondria or chloroplasts, scarcely resemble free-living organisms. Assuming peroxisomes evolved from ingested bacteria, describe three features mitochondria retain but peroxisomes apparently lost over hundreds of millions of years. Select all that apply.
|
QUESTION 1
Which of the following statements about the bacterial cytoplasmic membrane is false?
a. | It resists attachment of the bacterial chromosome to its inner surface. | |
b. | It contains a protein complex that drives ATP synthesis. | |
c. | It is asymmetric. | |
d. | It consists of relatively equal amounts of phospholipids and proteins. |
1 points
QUESTION 2
Which of the following statements regarding Mycobacteria is false?
a. | The genome has relatively low Guanine (G) and Cytosine (C) content. | |
b. | The cytoplasmic membrane is surrounded by a polymer (peptidoglycan) consisting of alternating N-Acetylglucosamine (NAG) and N-Acetylmuramic (NAM) acid units. | |
c. | It infects approximately one-third of the global human population. | |
d. | It has a Gram-positive cell wall with an additional waxy lipid layer of mycolic acid. |
1 points
QUESTION 3
Which of the following outer membrane porins enables Mycobacteria to adapt to acidic and intracellular environments, and shows homology to outer membrane porin A?
a. | OmpATb. | |
b. | OmpA. | |
c. | MspA. | |
d. | Lipid A. |
1 points
QUESTION 4
Based on your understanding of bacterial membranes, which of the following is not likely to be found in an E. coli outer membrane?
a. | Membrane-anchored enzymes. | |
b. | Mycolic acid. | |
c. | Lipopolysaccharide. | |
d. | Porin channels. |
1 points
QUESTION 5
Based on the conclusions of this paper, which of the following statements would the author most likely disagree with?
a. | Some archaeon do not contain all of the genes essential for life. | |
b. | The membrane structures of prokaryotes show far greater diversity than those of eukaryotes. | |
c. | As demonstrated in this definitive report, scientists have a great understanding of the majority of basic functions and evolution of bacterial membranes. | |
d. | The outer membrane (and its associated components) of archaea, Gram-negative bacteria, and Gram-positive bacteria likely evolved independently of one another. |
1 points
QUESTION 6
Which of the following is not true for Gram-negative, acid-fast, and archaeal membranes?
a. | They modify their lipid content in response to environmental changes. | |
b. | They have co-evolved the same outer membrane composition and structure. | |
c. | They all have a cytoplasmic membrane. | |
d. | Membrane transport proteins regulate nutrient uptake and waste removal. |
1 points
QUESTION 7
Compared to Mycobacteria, Gram-negative bacterium contain:
a. | More mycolic acid. | |
b. | Pores of increased length. | |
c. | Less peptidoglycan. | |
d. | 50-fold-lower numbers of porins. |
1 points
QUESTION 8
Archaea are found to survive in strongly acidic lakes compared to bacteria and Eukaryotes. Which of the following supports this claim according to the study?
a. | The presence of L-glycerol ether linked lipids in Archaea membranes. | |
b. | The presence of D-glycerol ether linked lipids in Archaea membranes. | |
c. | The presence of L-glycerol ester linked peptidoglycans in Archaea membranes. | |
d. | The presence of L-glycerol ester linked lipids in Archaea membranes. |
1 points
QUESTION 9
Based on your understanding of the symbiotic relationship between Nanoarchaeum equitans and Ignicoccus, which of the following below is not true?
a. | The membrane lipids of N. equitans are synthesized by Ignoccocus. | |
b. | In exchange for membrane lipids, N. equitans provide Ignicoccus with many essential cytoplasmic enzymes. | |
c. | N. equitans lack enzymes capable of catalyzing lipid biosynthesis. | |
d. | Intraperiplasmic vesicles produced by Ignicoccus allow for lipid transfer to N. equitans. |
1 points
QUESTION 10
What is the role of hydrogen bonds in bacteria, as mentioned in the article?
a. | They mediate transmembrane electron flow. | |
b. | They mediate lipid biosynthesis. | |
c. | They help to stabilize the cytoplasmic membrane. | |
d. | They are responsible for the selective permeability of the cytoplasmic membrane. |