Section 3 Diversity: Acellular and acellular cycle, Prokaryotes (bacteria And Archaea)

Question 1

Viruses

Answer 1

acellular, non-living
Active when they invade a host cell

Cannot
- copy RNA
- make RNA or protein
- replicate
Need the host mechanism to do it
Classified based on host

Question 2

Lytic cycle

Answer 2

Phase attaches to cell (phage DNA and bacterial chromosome),
phage injects its DNA, phase DNA circularizes (genetic recombination)

new phage DNA and proteins are synthesize , new phases assemble,
the cell lyses, releasing phases, newly released phage may infect another cell

Question 3

Lysogenic cycle

Answer 3

Phase attaches to cell (phage DNA and bacterial chromosome),
phage injects its DNA, phase DNA circularizes,

Phage DNA inserts into the bacterial chromosome, the lysogenic bacterium replicates normally, copying the Prophase at each cell division, many cell divisions = environmental stress

Question 4

HIV - AIDS

Answer 4

Human immunodeficiency virus

Acquired immunodeficiency syndrome
Retro virus - use RNA as template to make DNA

Carry reverse transcriptase - enzyme catalyze a reverse trancription process (synthesize DNA from RNA)
= immunocompromised

Question 5

Viroids

Answer 5

Infectious RNA
Infects plants mostly

Question 6

What infects plants and is an infectious RNA

Answer 6

Viroids

Question 7

Prions

Answer 7

More dangerous
Infectious proteins
Causes neurodegeneration in animal (mostly)
- denatured proteins

Question 8

Differences between Lytic cycle and Lysogenic cycle

Answer 8

Lytic cycle
1) new phase DNA and proteins are synthesized
2) New phases assemble
3) Cell lyses and newly released phage may infect another cell

Lysosgenic Cycle
1) Phage DNA inserts into bacterial chromosome
2) The Lysogenic bacterium replicates normal, copying prophase at each cell division
3) environmental stress - goes through cycle again
4) Resulting in many cell divisions

Question 9

SImilarities between Lytic cycle and Lysosgenic cycle

Answer 9

Phage attaches to cell and phage injects it DNA into host cell

Phage DNA circularizes

Can either go in Lytic cycle OR Lysosgenic cycle

Question 10

Spike/Viral proteins

Answer 10

Proteins surrounding virus, binds to host proteins which allows access to host therefore releasing genetic material

Question 11

Reverse transcriptase

Answer 11

HIV - aids carry’s reverse transcriptase, which is an enzyme that catalyses a reverse transcription process (synthesize DNA from RNA)

Question 12

What are the 3 domains of life