Binary fission, Viruses

Question 1

Binary fission

Question 2

what is binary fission?

Answer 2

Binary fission is the process through which asexual reproduction happens in bacteria.

Question 3

describe the process of binary fission?

Answer 3

Loop of DNA and plasmids replicate. the main DNA loo is only replicated once, but plasmids can be replicated loads of times

the cell gets bigger and the DNA loops move to opposite poles of the cell

the cytoplasm begins to divide and a new cell wall begins to form

the cytoplasm divides and two daughter cells are produced. Each daughter cell has one copy of circular DNA, but can have a variable number of copies of plasmids

Question 4

Viruses

Question 5

why are the properties of viruses?

Answer 5

acellular and non-living

Question 6

why are viruses classed as non-living?

Answer 6

• no energy - metabolism
• do not grow
• produce no waste products
• don’t reproduce independently but must replicate by invading live host cells

Question 7

All viruses contain..?

Answer 7

• capsid - a protein coat to protect the nucleic acid
• Nucleic acid (DNA, RNA)

Question 8

some viruses contain?

Answer 8

• a lipid envelope to assist entry to host cells
• enzymes
• attachment proteins

Question 9

explain in steps how viruses reproduce?

Answer 9

• virus attaches to host cells
• using attachment proteins to bind to complimentary receptor protein on the host cell
• injects DNA/ RNA into the host cell
• genetic information and proteins are replicated by the host cell
• Viral components assemble
• replicated virus is then released from the host cell

Question 10

FINISH