Question:
True or false. Animal viruses will utilize host cell machinery during the replication process. Explain your answer.
Answer
True
Explanation
Animal viruses require a host cell in order to replicate and spread. Once a virus infects a host cell, it incorporates its genetic material into the host cell's genome. Depending on the type of virus, it may follow either a lytic cycle or a lysogenic cycle.
During the lytic cycle, the virus takes control of the host cell's machinery to produce viral proteins and replicate its own genome. The host cell's resources are redirected towards the production of new viral particles until the host cell ruptures, releasing the newly formed viruses into the surrounding environment. This cycle results in the rapid spread of the virus and often leads to the destruction of the host cell.
In contrast, during the lysogenic cycle, the viral genome integrates into the host cell's DNA and remains dormant for a period of time. The viral DNA is replicated along with the host cell's genome during cell division, which allows the virus to be transmitted to daughter cells. At some point, the virus may be triggered to enter the lytic cycle, at which point it takes over the host cell's replication machinery and begins to replicate rapidly.
Therefore, animal viruses cannot replicate on their own and require a host cell to carry out the process of replication. Once inside the host cell, the virus can undergo either a lytic or lysogenic cycle, which enables the virus to spread and infect other cells.
True or false. A DNA and RNA animal virus would vary in their process of genome replication and construction of new virus. Explain your answer.
Answer
TRUE
Explanation
With DNA, a DNA virus can easily integrate into the normal replication process of the host cell, while with RNA, the RNA virus needs to reverse transcribe its genome into DNA first before it hijacks the host cell replication machinery. The two vary, that is why RNA viruses have an enzyme called reverse transcriptase which converts the RNA into DNA, so as to easily integrate with the host cell DNA and replicate. DNA virus does not need the enzyme and can easily be replicated by the host cell replication machinery.
True or false. Budding requires that viral attachment proteins are embedded in the host cell membrane before it can occur. Explain your answer.
Answer
True
Explanation
Viruses are released from the host cell after maturity through budding and lysis. Budding involves the attachment of the viral segment with the host cell membrane. Normally, it undergoes the same process as proteins undergo after translation, which is from the endoplasmic reticulum, to the golgi apparatus and lastly to the cell membrane. At the cell membrane, the virus is released together with a segment of the cell membrane which forms an envelope.
Question:
A new chemotherapeutic drug kills bacteria but not humans. Discuss the possible ways the drug may selectively act on bacterial cells.
Answer
A chemotherapeutic drug can kill a bacterial cell by targeting cell wall synthesis and the formation of peptidoglycan, which is absent in human cell.
A drug may target a specific metabolic pathway in bacterial cell, which is not present in human cell. For example, human cell obtains folic acid through diffusion while a bacteria cell makes its own folic acid. Inhibiting the synthesis prevents only bacteria cell from growth.
Explanation
Most bacteria produce a cell wall that is composed of peptidoglycan, which is not present in human cells. A chemotherapeutic drug may target the final step of peptidoglycan synthesis that involves cross-linking which results in a bacteria cell wall that is fragile and which can easily burst which kills the bacteria while causing no harm to human cell.
All cells require folic acid, which can easily diffuse into human cell but not to bacterial cells. This means that a bacterial cell has to synthesize its own folic acid. A chemotherapeutic drug can target this metabolic pathway that is not present in human cell, which prevents the bacterial cell from making folic acid, and since folic acid is vital for bacterial growth, its absence inhibits the growth of bacterial cells while causing no harm to human cells.
A patient has been infected with a bacteria, the macrophages get to work by consuming the bacteria ,this is an example of
Adaptive immunity
ig mediated immunity
innate immunity
Specific immunity
Answer
innate immunity
Explanation
The body's immune system is divided into two main branches; the adaptive and the innate immune system. The innate immunity is a type of nonspecific defense mechanism that provides immediate protection to the body whenever an antigen appears. Among the components of the innate immune system includes the blood chemicals, physical barriers like the skin, and the immune cells which attack foreign cells like a bacteria cell.
An Advantage of a fever is that it causes tachycardia which helps the patient pump more blood to the places that need it more
true
false
Answer
TRUE
Explanation
Fever is caused by high temperatures above normal as a result of infection. To reduce the effects of infection, there is an increase in temperature in the tissues infected. The body tries to deal with high temperature caused by fever through high heart rate, breathing rate and blood circulation to the skin. High heart rate (tachycardia) is beneficial to the healing process because more white blood cells are taken to the site of infection speeding healing process.
An Advantage of a fever is that it causes tachycardia which helps the patient pump more blood to the places that need it more
true
false
Answer
TRUE
Explanation
Fever is caused by high temperatures above normal as a result of infection. During infection, the body increases the heart rate to pump more blood to the tissues infected. By doing so, more white blood cells are pumped into those tissues which helps speed the process of healing and eliminating the bacteria.
