1. Prokaryote vs. Eukaryote

2. Prokaryote vs. Eukaryote
1st division
Life
Prokaryotes
Eukaryotes
Bacteria
Archea
Protist
Fungi
Plants
Animals

3. Prokaryotes Prokaryotes (bacteria and archea) Lack a true nucleus
Keep DNA in nucleoids
No membrane bound organelles
Many are anaerobic
Do not require O2
Unicellular

4. Eukaryotes Eukaryotes (protists, plants, fungi, animals)
Presence of a nucleus
Presence of membrane bound organelles
For example Mitochondria to give energy
Most are aerobic
Require O2 for cellular respiration
Most are pluricellular

5. Summary chart Prokaryotes Eukaryotes Lack a true nucleus
No membrane bound organelles
Many are anerobic
Unicellular
Eukaryotes
Presence of a nucleus
Has membrane bound organelles
Most are aerobic
Mostly pluricellular

6. But where do viruses fit in?
Debate over whether viruses are “alive”
A) Non-living arguments
1. Cannot live independently (require a host or remain dormant)
2. Not Cellular
B) Living arguments
1. Contain genetic material (RNA and DNA)
2. Reproduce

7. Classifying viruses Classification based on 1. Capsids
Protein coat that surrounds the genetic material of a virus
Spherical
Cylindrical
Crystalline

8. Classifying viruses 2. Diseases they cause
Viruses that affect humans are divided into 21 groups based on the differences in their genome and replication methods

10. Going viral (how viruses replicate)
Virus replication (No cellular division)
1. The Lytic cycle
Kills host cell
Process
Virus binds to host (attachment)
Injects the genetic material into the host cell (entry)
The host replicates the viral genetic material (replication)
New viral particles are assembled (assembly)
The host cell breaks (lysis) and releases new viral particles (release)

11. The lytic cycle 1. Attachment 2. Entry 3. Replication 4. Assembly
5.a) Lysis
5. b) Release

12. Virus replication 2. the Lysogenic cycle
As the viral RNA becomes part of the cells chromosomes, the onset of disease can be postponed until the virus goes into its lytic cycle
Process
Attachment
Entry
Viral DNA becomes part of the host cell’s chromosomes (provirus formation)

13. The lysogenic cycle
Attachment
Entry
Provirus Formation

14. Viral disease
Cyclical symptoms can be explained via the replication method of a virus
E.g cold sores
Appear during the lytic cycle
Disappear during the lysogenic replication cycle

15. Virus working for us Virus use in biotechnology
ability to direct the activity of the hosts cell DNA
Addition of a specific gene into the virus
Virus can deliver and force organism to replicate that gene

16. Prions
Prions
Protein
Do not contain RNA or DNA (not a virus)
Becomes harmful when it changes its molecular shape
Cause several deadly brain diseases
Creutzfeld-Jakob disease
Mad-cow disease in bovine