Bacterial structure 1

Previous exams & Formative:

1- Bacterial chromosome is composed of: a. Double stranded DNA b. Double stranded RNA c. Single stranded DNA d. Single stranded RNA

2- When flagella are distributed all around a bacterial cell, the arrangement is called: a. Polar b. Peritrichous c. Encapsulated d. Monotrichous

3- Differences between eukaryotic and prokaryotic cells include all of the followings Except: a. Eukaryotic cells have mitochondria b. Prokaryotic cells have more complex cell walls c. Eukaryotic cells have cilia and flagella with complex structure d. The prokaryotic cells divide by binary fission.

4- The envelope surrounding the nucleocapsid of some viruses is made up of which of the following structures: a. Lipoproteins b. Peptidoglycan c. Lipopolysaccharides d. Chitin

5- A small circular double stranded DNA that is capable of autonomous replication is called: a. Bacterial chromosome. b. Plasmid c. Phage d. Transposon

6- Genetic material of bacterial cell is composed of: a. Single linear bacterial chromosome only b. Single circular bacterial chromosome only c. Single circular bacterial chromosome and extra-chromosomal elements. d. Plasmids and phages only

7- Causes of marked resistance of spores include the following Except: a. Thick spore cortex and tough coat. b. Their dehydrated state. c. Their very high metabolic and enzymatic activity. d. The bacterial spores contain large amount of dipicolinic acid

8- The significance of the plasma membrane includes all the following Except: a. It selectively allows some molecules to pass into the organism b. Supplies the cell with energy c. Provides enzymes and lipid carriers for cell wall synthesis. d. Responsible for the staining affinity of the bacterial cell

9- All the following represent bacterial cell wall functions Except: a. It is a rigid structure that maintains shape of bacteria. b. Excretion of pathogenicity proteins and some exotoxins c. Protects the cytoplasmic membrane from bursting in hypotonic solutions d. Determine the reaction to Gram stain

10- Functions of flagella include all the following Except: a. Organ of locomotion and chemotaxis b. Antigenic function used for typing and diagnosis. c. Responsible for adhesion and attachment to mucosa d. Penetrating through viscid mucus secretions and epithelial barriers and spreading throughout body fluids and tissues

11- The genetic material in virus is: a. DNA only b. RNA only c. DNA or RNA d. DNA and RNA

12- A main component of the cell wall of gram -ve bacteria that is concerned with pathogenesis is: a. Enterotoxin. b. Teichoic acid c. Endotoxin d. Peptidoglycan e. Pili

13- What is responsible for the endotoxin activity of LPS: a. Core polysaccharide b. O antigen c. Lipid A d. H antigen e. K antigen

14- Which of the following structures is involved in bacterial attachment cell surfaces: a. Flagella b. Pili c. Mesosomes d. Peptidoglycan e. Teichoic acid

15- Peptidoglycan layer is present in large quantity in: a. Gram-positive bacteria b. Gram-negative bacteria c. Fungi d. Algae

16- Which of the following is NOT the basic shape of the bacteria: a. Rod shape b. Square shape c. Comma shape d. Spiral shape

17- Differential staining of bacteria on Gram staining is due to: a. Difference in the cell wall layer components of Gram positive and Gram negative bacteria b. Difference in the cell structure of Gram positive and Gram negative bacteria c. Difference in the mode of nutrition of Gram positive and Gram negative bacteria d. None of the above

18- The ability of bacteria to change their morphological form frequently is: a. Lysogeny b. Pleomorphism c. Alter morphism d. None of these

19- bacterial flagella is made up of: a. Microtubules b. Tubulin c. Flagellin d. Spinin

20- Surface appendage of bacteria meant for cell-cell attachment during conjugation: a. Pilli b. Bacterial structure c. Flagella d. Spinae e. Cilia

21- The region where bacterial genome resides is termed as: a. Nucleus b. Cytoplasm c. Nucleoid d. Ribosome

22- The organ of locomotion of bacteria is: a. Capsule b. Flagella c. Slime d. Fimbriae

23- H antigen is a: a. Somatic antigen b. Flagellar antigen c. Capsular antigen d. Virulent antigen

24- Plasmid is a: a. Extrachromosomal genetic element in the bacterial chromosome b. Segment of DNA carrying codons specifying for a particular polypeptide c. Triple nucleotide group, coding one specific amino a d. Segment of rna

25- Bacterial cell wall is made up of: a. Chitin b. Cellulose c. Dextran d. Peptidoglycan

26- K antigen is a: a. Somatic antigen b. Flagellar antigen c. Capsular antigen d. Virulent antigen

27- Gram positive microorganisms have: a. Violet color b. Pink-red color c. Green color d. Black color

28- An outer covering in some bacteria that protects them from phagocytosis by host cells is: a. Capsule b. Cell wall c. Flagellum

29- A nontoxic virulence factor that promotes survival of a pathogen by protecting it from phagocytosis is : a. Pili b. Capsule c. An enzyme d. Mucous membrane

30- Which of the following is not true related to endotoxins: a. Endotoxins are secreted from cells b. Cause of endotoxic shock c. Produced by gram negative microorganisms d. Cause fever