Agriculture Exams (Agri Croppro) - Free Online Reviewers

#260. A number of economically important virus diseases have been ravaging crops in the Philippines. Which of the following is not a virus disease?

A abaca/banana bunchy to

B coconut cadang-cadang

C rice tungro

D papaya ring spot

Answer: abaca/banana bunchy to

#261. Virus genome organization means the arrangement of the

A nucleic acid with its protein coat

B amino acids in all its coat proteins

C various genes along the whole nucleic acid strand

D sugars with its coat protein

Answer: sugars with its coat protein

#262. In plant viruses having a double stranded nucleic acid genome, which of the following is/are not true?

A strands are held together by hydrogen bonds

B strands are in opposite polarities

C thymine or uracyl pairs with adenine

D strands are held together by nitrogen bonds

Answer: thymine or uracyl pairs with adenine

#263. Which of the following would contribute highly to a fast characterization of a plant virus? It being

A a virus with known physical properties in vitro

B transmitted only by certain species of a vector

C infects specialized cells of its host

D easily mechanically transmitted

Answer: easily mechanically transmitted

#264. The biological properties of a virus are reflected through infectivity assays. this type of assay ...

A only purified viruses can be tested

B both purified and viruses in sap can be tested

C only infectious particles cause infections

D both infectious and non-infectious particles necessary for infection

Answer: only infectious particles cause infections

#265. Plant viruses with genomes, whether composed of one or more than one strand, enclosed in a single coat protein is a

A helper virus

B satellite virus

C monocomponent virus

D dependent virus

Answer: monocomponent virus

#266. From the site of inoculation, plant viruses spread through the plant in a slow cell-to-cell spread through the

A plasmodesmata

B phloem

C stomata

D xylem

Answer: plasmodesmata

#267. Which of the following is a barrier to virus movement through the plant?

A movement from the first infected cell

B movement out of parenchyma cells into vascular tissues

C movement out of the vascular tissue into the parenchyma of an invaded leaf

D movement out of the stylet of the vector among epidermal cells of the plant

Answer: movement from the first infected cell

#268. The survival and spread of certain plant viruses depend on

A amount of virus produced in infected tissues

B its degree of stability

C persistence in its vector

D all of the above

Answer: all of the above

#269. Which virus would most likely survive?

A a virus that kills its host plants with a rapidly developing systemic disease

B a virus that causes only mild or moderate disease that allows the plant to survive and reproduce effectively

C a virus not does not replicate in plants

D a virus that will not infect and cause any disease

Answer: a virus that causes only mild or moderate disease that allows the plant to survive and reproduce effectively

#270. Which of the following would not contribute to plant virus disease epidemics?

A presence of active and mobile vectors

B planting of susceptible hosts

C monocropping

D multicropping

Answer: multicropping

#271. Roguing as a virus disease control strategy is worthwhile or effective if disease spread

A is occurring rapidly relative to the lifetime of the crop

B is occurring slowly relative to the lifetime of the crop

C is occurring simultaneously on several hosts

D is occurring at random

Answer: is occurring slowly relative to the lifetime of the crop

#272. A seed infected with a virus is an important source of infection since the seed introduces

A the virus into the crop at a very early stage

B a concentrated foci of infection throughout the crop

C the virus into the crop at all stages of the crop

D the virus into the crop at a late stage

Answer: the virus into the crop at a very early stage

#273. When a virus preparation is treated with mild alkali (0.3 M NAOH), the following biomolecules would be are expected to be cleaved

A Proteins

B DNAs

C RNAs

D polysaccharides

Answer: RNAs

#274. A virus preparation which is not so pure (i.e. contains host compohents) when used to immunize a rabbit, the rabbit will

A produce antibodies against the virus only

B produce antibodies of the host plant component only

C produce antibodies to both the virus and host component not

D produce any antibody

Answer: produce antibodies to both the virus and host component not

#275. Which of the following is a form of susceptible response by the plant to a virus infection?

A production of local lesions

B relatively fast appearance of severe symptoms

C slow virus multiplication and spread in it

D slow appearance of symptoms

Answer: relatively fast appearance of severe symptoms

#276. Which of the following is true of a virus as an antigen?

A induces the production of antibodies and reacts specifically to the antibodies

B should react to all antibodies produced

C induces only the production of antibodies in a warm-blooded animal

D not recognized by antibodies in immunized animals

Answer: induces the production of antibodies and reacts specifically to the antibodies

#277. Which of the following is true of a virus as an antigen?

A induces the production of antibodies and reacts specifically to the antibodies

B should react to all antibodies produced

C induces only the production of antibodies in a warm-blooded animal

D not recognized by antibodies in immunized animals

Answer: induces the production of antibodies and reacts specifically to the antibodies

#278. Which of the following is true of a virus as an antigen?

A induces the production of antibodies and reacts specifically to the antibodies

B should react to all antibodies produced

C induces only the production of antibodies in a warm-blooded animal

D not recognized by antibodies in immunized animals

Answer: induces the production of antibodies and reacts specifically to the antibodies

#279. Which of the following is true of a virus as an antigen?

A induces the production of antibodies and reacts specifically to the antibodies

B should react to all antibodies produced

C induces only the production of antibodies in a warm-blooded animal

D not recognized by antibodies in immunized animals

Answer: induces the production of antibodies and reacts specifically to the antibodies

Agriculture Exams (Agri Croppro) – Page 14

#260. A number of economically important virus diseases have been ravaging crops in the Philippines. Which of the following is not a virus disease?

#261. Virus genome organization means the arrangement of the

#262. In plant viruses having a double stranded nucleic acid genome, which of the following is/are not true?

#263. Which of the following would contribute highly to a fast characterization of a plant virus? It being

#264. The biological properties of a virus are reflected through infectivity assays. this type of assay ...

#265. Plant viruses with genomes, whether composed of one or more than one strand, enclosed in a single coat protein is a

#266. From the site of inoculation, plant viruses spread through the plant in a slow cell-to-cell spread through the

#267. Which of the following is a barrier to virus movement through the plant?

#268. The survival and spread of certain plant viruses depend on

#269. Which virus would most likely survive?

#270. Which of the following would not contribute to plant virus disease epidemics?

#271. Roguing as a virus disease control strategy is worthwhile or effective if disease spread

#272. A seed infected with a virus is an important source of infection since the seed introduces

#273. When a virus preparation is treated with mild alkali (0.3 M NAOH), the following biomolecules would be are expected to be cleaved

#274. A virus preparation which is not so pure (i.e. contains host compohents) when used to immunize a rabbit, the rabbit will

#275. Which of the following is a form of susceptible response by the plant to a virus infection?

#276. Which of the following is true of a virus as an antigen?

#277. Which of the following is true of a virus as an antigen?

#278. Which of the following is true of a virus as an antigen?

#279. Which of the following is true of a virus as an antigen?