49. CYTOPLASMIC MEMBRANE

Question 1

1. What is another term for the Cytoplasmic Membrane?

Answer 1

• the Plasma Membrane

Question 2

2. What is the Cytoplasmic Membrane composed of?

Answer 2

1. Phospholipids
2. Proteins

Question 3

3. What are the 4 Phospholipids that we can find in Prokaryotic Plasma Membranes?

Answer 3

1. PG = Phosphatidyl-Glycerol
2. PE = Phosphatidyl- Ethanolamine
3. PA = Phosphatidic Acid
4. DPG = Diphisphatidyl-Glycerol

Question 4

4. What kind of permeability does the Cytoplasmic Membrane have?

Answer 4

• it is semi permeable
• this means that it has Selective Permeability

Question 5

5. Does this diagram of the Plasma Membrane make sense?

Answer 5

• yes

Question 6

6. What can we not find in Prokaryotic Cells?

Answer 6

• they lack complex compartmentalisation
• they do not have a membrane-bound nucleus
• they do not have membrane-bound organelles

Question 7

7. What are Mesosomes?

Answer 7

• they are the infoldings of the Plasma Membrane
• they are specialised membranes
• the perform metabolic functions
  (in some Prokaryotes)

Question 8

8. What is the function of Mesosomes?

Answer 8

1. IN AEROBIC PROKARYOTES
   - they are responsible for Cellular Respiration
2. IN CYANOBACTERIA
   - they are responsible for Photosynthesis
3. DURING CYTOKINESIS
   - they are responsible for the formation of the
   diaphragm
4. AT THE END OF BINARY FISSION
   • they are responsible for Cell Wall Deposition

Question 9

9. Does this image of Mesosomes make sense?

Answer 9

• yes

Question 10

10. What are Ribosomes?

Answer 10

• they are made of the RNA
  and proteins

Question 11

11. What is the function of Ribosomes?

Answer 11

• Protein Synthesis

Question 12

12. What are Polysomes?

Answer 12

• they are made of Ribosomes that are found on a single
  mRNA
• this helps with bettering the translation process

Question 13

13. What ca be said about the subunits of Prokaryotic Ribosomes?

Answer 13

• their subunits are different than that of Eukaryotes

Question 14

14. What are the 2 types of subunits of Prokaryotic Ribosomes?

Answer 14

1. SMALL SUBUNITS
   
   • 30 S
2. LARGE SUBUNITS
   
   • 50 S

Question 15

15. What can be said about the inhibiting capabilities of some antibiotics?

Answer 15

• they can inhibit Bacterial Ribosomes
• without inhibiting Human Eukaryotic Ribosomes

EXAMPLE:
- Tetracycline

Question 16

16. What is the Nucleoid?

Answer 16

• this is the region that contains the Prokaryotic
  Chromosome
• it is not surrounded by a Nuclear Membrane

Question 17

17. What is the Prokaryotic Chromosome?

Answer 17

• this is a double-stranded
• circular
• DNA molecule

Question 18

18. List 3 characteristics of the Prokaryotic Genome.

Answer 18

1. Smaller than the Eukaryotic Genome
2. Absence of Histones
3. Supercoiled to fit into the Nucleoid Region

Question 19

19. What structure is only present in Eukaryotic Chromosomes?

Answer 19

• Histones

Question 20

20. What kind of elements can Prokaryotes contain?

Answer 20

• they can contain extra-chromosomal elements

Question 21

21. List the 2 extra-chromosomal elements we can find in Prokaryotes?

Answer 21

1. Plasmids
2. Bacteriophages (Phages)

Question 22

22. What are Plasmids?

Answer 22

• they are small, circular DNA molecules
• some of them carry genes that are responsible for
  Antibiotic Resistance
• these are known as R Plasmids

Question 23

23. What are Bacteriophages (Phages)?

Answer 23

• these are the viruses that infect Bacteria
• they have a DNA genome

Question 24

24. Does this image of Prokaryotic Chromosomes make sense?

Answer 24

• yes

Question 25

25. Does this image make sense?

Answer 25

• yes