Describe how a replication-defective virus may be generated
What will be an ideal response?
Ans: A provirus may reside adjacent to a c-onc gene in a host genome. (A c-onc gene is homologous to a v-onc gene carried by transducing viruses.) A deletion may join the provirus to the c-onc gene; after transcription, introns are removed from both the proviral and c-onc sections of the RNA, and it is packed into a viral particle. Recombination between this RNA and an intact viral RNA generates an RNA with the appropriate terminal repeats, but carrying a v-onc gene and lacking some proviral sequences, making it unable to replicate.
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Match the following items with the correct phrases.
_______1. Measles _______2. Viral hemorrhagic fever _______3. Chickenpox _______4. Smallpox _______5. Cold sores A) Ebola virus B) Herpes simplex virus C) Variola virus D) Varicella-zoster virus E) Rubeola virus
List three properties that all forms of cancers share and summarize the origin of these properties
What will be an ideal response?
Once photons are harvested by the pigment molecules in the light-harvesting complex, where is the energy delivered next?
a. the lumen of the thylakoid b. the outer membrane of the chloroplast c. the reaction center of the photosystem d. the stomata of the leaf
An oncogene is
a. a normal gene that promotes mitosis. b. a gene that codes for a growth factor that stimulates cell division. c. a gene that codes for tumor suppressing proteins. d. a mutated gene that results in tumors. e. more than one of these