Bacterial Shape, Size & Structure Quiz

Q21. Which structure protects bacteria from phagocytosis?

 A) Capsule
 B) Plasmid
 C) Flagella
 D) Fimbriae

Q22. Pili are involved in:

 A) Motility
 B) Attachment and conjugation
 C) Toxin production
 D) Respiration

Q23. What structure provides bacterial motility?

 A) Pilus
 B) Flagellum
 C) Ribosome
 D) Capsule

Q24. Which structure allows bacteria to survive harsh conditions?

 A) Capsule
 B) Mesosome
 C) Spore
 D) Fimbriae

Q25. What structure contains antibiotic resistance genes?

 A) Flagella
 B) Plasmid
 C) Capsule
 D) Porins

Q26. Bacterial granules serve as:

 A) Waste
 B) Nutrient storage
 C) Toxins
 D) Transport proteins

Q27. The glycocalyx helps bacteria:

 A) Move
 B) Attach to surfaces
 C) Evade heat
 D) Digest antibiotics

Q28. Which bacteria lack a cell wall?

 A) Mycoplasma
 B) Staphylococci
 C) Bacilli
 D) Cocci

Q29. Teichoic acid is found in:

 A) Gram-negative bacteria
 B) Mycoplasma
 C) Gram-positive bacteria
 D) Fungi

Q30. The outer layer of gram-negative bacteria includes:

 A) Teichoic acid
 B) Polypeptides
 C) Lipopolysaccharide
 D) Chitin

✅ Answer Key

Q21: A) Capsule         Q22: B) Attachment and conjugation         Q23: B) Flagellum         Q24: C) Spore         Q25: B) Plasmid         Q26: B) Nutrient storage         Q27: B) Attach to surfaces         Q28: A) Mycoplasma         Q29: C) Gram-positive bacteria         Q30: C) Lipopolysaccharide

Q31. Peptidoglycan is thicker in:

 A) Gram-positive bacteria
 B) Gram-negative bacteria
 C) Mycoplasma
 D) Viruses

Q32. Which bacteria have a periplasmic space?

 A) Gram-positive
 B) Gram-negative
 C) Fungi
 D) Viruses

Q33. The endotoxin in gram-negative bacteria is part of:

 A) Peptidoglycan
 B) Lipid A
 C) Teichoic acid
 D) Capsule

Q34. Which protein allows molecule passage in gram-negative bacteria?

 A) Teichoic acid
 B) Porin
 C) Histones
 D) Fimbriae

Q35. Porin channels help transport:

 A) DNA
 B) Water and solutes
 C) Teichoic acid
 D) Lipids

Q36. Which type of bacterial wall has lipoproteins and phospholipids?

 A) Gram-positive
 B) Gram-negative
 C) Acid-fast
 D) Mycoplasma

Q37. Which statement is true about Mycoplasma?

 A) They have thick cell walls
 B) They lack a cell wall
 C) They are fungi
 D) They are viruses

Q38. Which bacterial structure is made of cross-linked peptidoglycan?

 A) Capsule
 B) Cell wall
 C) Ribosome
 D) Plasmid

Q39. What distinguishes gram-negative bacteria structurally?

 A) Teichoic acid
 B) Thick peptidoglycan
 C) Lipopolysaccharide outer layer
 D) No ribosomes

Q40. What is a unique feature of bacterial ribosomes?

 A) 80S size
 B) Sterol binding
 C) 50S and 30S subunits
 D) Membrane-bound

✅ Answer Key

Q31: A) Gram-positive bacteria         Q32: B) Gram-negative         Q33: B) Lipid A         Q34: B) Porin         Q35: B) Water and solutes         Q36: B) Gram-negative         Q37: B) They lack a cell wall         Q38: B) Cell wall         Q39: C) Lipopolysaccharide outer layer         Q40: C) 50S and 30S subunits