Read the two types of virus reproduction on the picture given. Then create a summary to perform your understanding.

Requirements : Write a concise summary (around 100-150 words) that explains the Virus Reproduction.

1. What is Lytic and Lysogenic Cycle.

2. Identify and list the steps of Lytic and Lysogenic Cycle.

3. Make a comparison between Lytic and Lysogenic Cycle to find the differences between two types of cycle.

Guidelines :

• Use your own words to summarize the process of photosynthesis.

• Make sure to include all the required points.

Submission :

Pleas submit and post your summary here, by press the button (+). Don't forget to name your padlet wall. Your submission count as your attendance.

Attachment: Bacteriophage uses proteins to Specific receptors on the surface of the host cell

Penetration: injects its DNA or RNA into bacterium cytoplasm

Replication: viral genome takes over the host cell machinery

Assembly: maturation

Release: cell burst and release new phages

Lysogenic cycle is a process where bacteriophage inserts its genetic material into the host bacterium chromosome, becoming a dormant prophage.

temperate phages: not virulent ones

Integration :The phages DNA integrates into the host bacteriums's chromosome

Prophage: integrated Viral DNA

Lysogen: Bacterium contains prophage

Replication: host cell divides

Dormancy: no new virus particles are produced and the host cell still alive and normal

Induction: exposure to stress or specific environmental cues

in summary Lytic cycle active infection and destroys the host cell but lysogenic is dormant phase viral DNA stay hidden inside host DNA

The Lysogenic Cycle is the life cycle that a non-virulent phage will accomplish. In this process, the virus does not kill the host. It will later inject its DNA into the host's cell. The phases that are included in this cycle are adsorption, penetration, integration, replication, induction, synthesis, assembly, and release.

The difference between those two cycles is:

1. For the Lytic cycle, it will directly kill the host cell, while the Lysogenic cycle does not immediately kill the host cell

The lysogenic cycle is a viral replication pathway where a virus's genetic material integrates into the host cell's DA and replicates along with it, without killing the host cell.

The five steps of the lytic cycle

1. Attechment (or Adsorption): The virus attaches to a spesific receptor on the surface of a host cell. For bacteriophages (viruses that infect bacteria), tail fibers on the virus bind to matching proteins on the bacterial cell wall.

2. Penetration (or entry): The virus injects its genetic material (DNA or RNA) into the host cell. In the case of bacteriophages, the virus uses a hollow tail tube to puncture the cell wall and inject its nucleic acid into the host's cytoplasm.

3. Biosynthesis (or Replication): The viral genetic material takes control of the host cell's machinery. It commandeers the host's ribosomes, enzymes, and other resources to rapidly synthesize copies of the viral genome and viral proteins. The host's own DNA is often degraded during this process.

4. Maturation (or Assembly): The newly created viral components are assembled into complete, functional virus particles, known as virions. This stage involves packaging the replicated viral genome into the nwely synthesized protein capsids.

5. Lysis (or Release): The new virions produce an enzyme, such as lysozyme, that breaks down the host cell wall. The cell then bursts (lyses) due to osmotic pressure, releasing hundreds of new virus particles to go on and infect other host cells.

   
   

   The main steps of the lysogenic cycle are: 

   1. Attachment: The virus attaches to a specific receptor on the surface of a host cell.

   2. Penetration: The virus injects its genetic material (DNA or RNA) into the host cell's cytoplasm.

   3. Integration: The viral DNA integrates itself into the host's chromosome, forming a prophage. This is the key distinguishing step from the lytic cycle.

   4. Replication (Dormancy): The prophage remains latent and is copied along with the host's own DNA every time the cell divides. As a result, the viral genetic material is passed on to all daughter cells.

   5. Induction: A change in environmental conditions, such as stress from UV light or chemicals, can trigger the prophage to become active. This causes the viral DNA to excise itself from the host chromosome, switching the virus into the lytic cycle.

   6. Lytic Cycle: Once induced, the virus proceeds with the final steps of the lytic cycle, which involves the production of new viruses, assembly, and the bursting of the host cell. This releases the newly formed viruses to infect other cells.

   The differences between lytic and lysogenic cycle are the host cell is destroyed by the aggressive, quick viral replication process known as the lytic cycle. The lysogenic cycle, on the other hand, is a more subdued, latent technique where the genetic material of the virus combines with the DNA of the host cell and replicates with it without instantly destroying the cell.
   

There are two distinct viral replication processes: the lytic and lysogenic cycles. A virus attaches itself to a host cell, inserts its genetic material, and then uses the host's machinery to create new viruses during the lytic cycle. Enzymes disintegrate the cell membrane after it has been assembled, rupturing the host cell and releasing the viruses, which results in cell death. The lysogenic cycle, on the other hand, permits the virus to stay dormant. When the host cell divides, the viral DNA becomes a part of the host's genome and replicates passively as a prophage. The prophage may activate and transition to the lytic cycle in specific environmental circumstances, creating new viruses and causing the cell to die. Therefore, whereas the lysogenic cycle allows the virus to remain hidden and replicate silently within the host for an extended period of time, the lytic cycle causes the virus to be produced immediately and destroys cells.

In the lysogenic cycle, the viral DNA integrates into the host’s chromosome and becomes part of the host’s genetic material, forming a prophage. The viral DNA is copied along with the host’s DNA during cell division, allowing the virus to remain dormant for a long time without damaging the cell. Under certain conditions, the prophage can become active and shift into the lytic cycle. The main difference is that the lytic cycle destroys the host cell quickly, while the lysogenic cycle allows long-term coexistence

2.       -  Steps of the Lytic Cycle:

·         Adsorption (Attachment)

·         Injection (Penetration)

·         Synthesis (Replication and Transcription/Translation)

·         Assembly (Maturation)

·         Lysis (Release)

      - Steps of the Lysogenic Cycle:

·         Adsorption (Attachment)

·         Injection (Penetration)

·         Integration

·         Prophage Replication (Dormant)

·         Induction (Entry into the Lytic Cycle)

3. For lytic viruses, they multiply rapidly and do not grow alongside their host. Once attached, they immediately destroy the host's cells. They also produce many new viruses quickly. And for the lysogenic, Lysogenic bacteria reproduce by coexisting with their host. They combine their DNA with the host's DNA and then go dormant until the right moment to wake up again.

2. There are five stage in the lytic cycle of a virulent phage:

1. Adsorption (menempel)

2. Penetration (meyuntikkan sel)

3. Replication (membuat replika)

4. Maturation (pematangan)

5. Release (pelepasan sel inang)

3. For the lytic cycle, it has visible symptoms, whereas the lysogenic cycle is invisible. Furthermore, the lytic cycle takes less time than the lysogenic cycle.

Lytic Cycle (The "Killer" Cycle)

This cycle ends with the host cell being destroyed.

1.      Attachment: Virus sticks to the host cell.

2.      Penetration: Virus injects its DNA/RNA into the cell.

3.      Biosynthesis: Viral DNA takes over and makes new viral parts.

4.      Assembly: New viral parts are put together to form complete viruses.

5.      Release (Lysis): The cell bursts, releasing new viruses to find new hosts.

Lysogenic Cycle (The "Dormant" Cycle)

This cycle allows the virus to replicate without immediately killing the host cell.

1.      Attachment & Penetration: Virus sticks to the host and injects its DNA/RNA.

2.      Integration: Viral DNA merges with the host's DNA (becoming a prophage).

3.      Latency: The host cell divides normally, copying the viral DNA along with its own DNA.

4.      Induction: A stress trigger (like UV light) causes the prophage to leave the host DNA and start the Lytic Cycle (leading to lysis).

 the two viral life cycles differ mainly in their immediate effect on the host cell.

-          The Lytic Cycle is a quick, destructive process where the virus immediately hijacks the host cell's machinery to mass-produce new viruses, resulting in the host cell's lysis (bursting) and death. In contrast

-          the Lysogenic Cycle involves the viral DNA integrating into the host's chromosome, becoming a dormant prophage. The host cell survives and continues to divide, passively replicating the viral DNA along with its own for many generations, until environmental stress triggers the viral DNA to induce (exit) and begin the destructive Lytic Cycle.

In summary, Viruses use two main strategies to multiply. The Lytic Cycle is the fast, destructive way: the virus takes over the cell, makes copies of itself, and forces the cell to burst (lyse), releasing new viruses.

The Lysogenic Cycle is the slow, hidden way: the viral DNA integrates into the host's DNA and remains dormant (a prophage). The virus copies itself every time the cell divides, spreading without immediately killing the host, until a stress signal makes it switch to the Lytic Cycle.

In the Lytic Cycle, the virus attaches to the host cell and injects its genetic material. The viral DNA takes control of the cell’s machinery to produce new virus particles. Once enough new viruses are made, the host cell bursts (lyses), releasing the new viruses to infect other cells.

In the Lysogenic Cycle, the viral DNA becomes part of the host cell’s DNA and stays inactive for a long time. The virus does not harm the cell immediately but is copied each time the host cell divides. Later, under certain conditions, the virus may switch to the lytic cycle.

The main difference is that the lytic cycle destroys the host cell quickly, while the lysogenic cycle allows the virus to remain hidden and inactive for a long period.

For the lytic cycle, its stages are :

1. Adsorption

The bacteriophage attaches to the bacteria wall when this happens it can also stop other bacteriophages from attaching to said bacteria.

2. Penetration

After attaching itself, it starts to inject its dna into the bacteria's cell. It then takes command of the host's machinery kind of like zombies.

3. Replication

It then makes the host's machinery produce more viral DNA or RNA, it synthesizes proteins that degrade the own host's DNA.

4. Maturation

Kind of like pregnancy

5. Release

Lysogenic cycle stages:

1. Adsorption

2. Penetration

3. Integration

4. Replication

5. Induction

6. Synthesis, Assembly, and Release

Comparison : Lyctic cycle is more aggresive and kills the bacteria while the lysogenic cycle is passive and doesn't

• lytic cycle : virus attaches to the cell, put its genetic material inside or usually called penetration, builds a new virus particles, makes a copies of itself (replication), and breaks the cell open release them.

• Lysogenic cycle : the virus puts its genetic materials into the cell's DNA and stays quiet for a long time. the cell keep dividing and the virus DNA is copied too. Later, it can be switch to the lytic cycle.

3. Comparison

   The lytic cycle destroys the cell quickly. while the lysogenic cycle stays inactive and does not harm the cell right way.

In the lysogenic cycle, the virus also enters the cell, but instead of making new viruses right away, its DNA joins the host’s DNA. The viral DNA is copied every time the cell divides. The steps are attachment, entry, integration, and replication. Later, the virus can switch to the lytic cycle.

The lytic cycle destroys the cell quickly, while the lysogenic cycle keeps the virus hidden and does not harm the cell immediately.