Prokaryotic Cells And Viruses

Question 1

what are eukaryotic cells?

Answer 1

-they are larger than prokaryotic cells and have a nucleus bounded by nuclear membranes

Question 2

what are prokaryotic cells?

Answer 2

-they are smaller than eukaryotic cells but have no nucleus and no nuclear envelope

Question 3

what is the structure of a bacterial cell?

Answer 3

• they have a murein cell wall
• they have a protective capsule of mucilaginous slime that is secreted around their cell wall
• inside the cell wall is the cell surface membrane within which is the cytoplasm which contains 70s ribosomes
• they have a circular strand of DNA
• they have small circular pieces of DNA called plasmids

Question 4

Where are bacteria cells found?

Answer 4

-they can occur in every habitat in the works and they are versatile, adaptable and successful due to their small size (0.1 to 10um in length)

Question 5

How do bacteria cells get energy?

Answer 5

-they store food reserves as glycogen granules and oil droplets

Question 6

what are viruses?

Answer 6

• they are acellular non living particles which are smaller than bacteria ranging from 20-300nm containing nucleic acids like DNA and RNA as genetic material but can only multiply inside living host cells
• the nucleic acid is enclosed within a protein coat called a capsid surrounded by attachment proteins or a further lipid envelope

Question 7

what Is the flagellum?

Answer 7

-used for movement

Question 8

what is the cytoplasm?

Answer 8

-jelly like substance containing enzymes and other soluble materials

Question 9

What is murein?

Answer 9

-a polymer of polysaccharides and peptides

Question 10

What do plasmids do?

Answer 10

• they can reproduce themselves independently and may give the bacterium resistance to harmful chemicals like antibiotics
• plasmids ate used extensively as vectors in genetic engineering