ENT Final Exam Quizzes and Practice Questions

"Pesticides are well-regulated in developing countries," your friend says. "They have as good a system for regulating pesticides as we do in the U.S." Your response to her is:

"Pesticides are often poorly regulated, inadequately labeled, and not labeled in the local language." Developing countries have a long way to go to guarantee safety for pesticide users. Pesticides banned in the US can be used, there is less concern or none at all about groundwater contamination in some countries, and worker safety is not being seriously considered. Our system is much better.

Which of the following is (are) NOT a practical solution(s) to protect biodiversity?

- clear cutting of forests - habitat fragmentation

We humans care about ecosystems because

- ecosystems provide services to us by creating a healthy environment - we use and manage ecosystems to provide many services

Humans use several specific insect services. These services include

- essential source of fiber and fat in some cultures - medicines in insects

Examples of biological control agents used against insects are:

- flies - wasps - beetles

Which of the following is a threat to biodiversity?

- habitat alteration - climate change - invasive species - pollution

The greatest threats to pollinating insects is/are

- honey bee parasites - pesticides - destruction of habitat

Why don't we use biological control all of the time for managing every pest?

- predators and parasites are more costly to produce than some insecticides - we dont want to use biological control in some areas, such as in our homes - biological controls are not available for all insect problems

Integrated pest management takes into account

- the biology of the pest species -the economic value of the crop - the control options available - the decision making process

Pesticides can get into our bodies:

- through our lungs by breathing vapors - by eating or drinking contaminated food or drink - through the skin

The adverse effects of pesticides include

- toxicity to nontarget organisms - pesticide resistance - environmental contamination

Integrated Pest Management (IPM) includes

- use of natural enemies like pests, like diseases, predators, and parasites - the option of not treating a pest - a system of monitoring and sampling density - proper pesticide use - consideration of the environment, economics, pest, host Many factors are involved in IPM, and together they make IPM a good tool for controlling pest populations.

Augmentation is one type of biological control. Which of the following statements are true about augmentation?

- usually conducted by growers - large numbers of natural enemies are released to immediately reduce a pest population (indunation) - small numbers of natural enemies are released at intervals starting when pest population is low (inoculative release)

In an ecosystem, which role(s) do insects play?

-primary consumers - secondary consumers - decomposers

Important medicines are found in plants, some of which need insects for pollination. Alkaloids, which cure some types of cancer, are an example of an important class of chemicals that come from plants. What percentage of plants have been analyzed thus far for alkaloids?

3%

The stage of animal decay where there are very high numbers of fly larvae that have spread to the inside of the decomposing body, which has a strong odor and is no longer bloated with gases, is

Active Decay

Which of the following practices is not appropriate for Integrated Pest Management (IPM)?

All of the above are appropriate - trapping pests - deciding to take no action against a pest - rotation of crops - use of predator and parasitoids - host plant resistance

Forensic Entomology is

Answer: None of the above The other choices: - the use of insects to determine environmental conditions - the study of insects and how they relate of global food shortages - the practice of raising insects for ecotourism

Which of the following crops is NOT pollinated by insects?

Answer: none of the above- they are all pollinated by insects Other choices: - cotton - alfalfa - apples -beans

Insect Growth Regulators (IGR):

B&C

The variety of life forms, the ecological roles they perform, and the genetic diversity they contain is called

Biodiversity

Which of the following insect orders does not pollinate plants?

Blattidae

Normally, the first insects to show up, within minutes, to a decaying animal body are

Blow Flies

The job of insect decomposers in ecosystems is to:

Break down dead complex organic matter into simple substances that plants can use again

Which is least toxic to humans?

Bug-Be-Dead (LD50= 4640) The larger the LD50 the less toxic it is.

The term that is used for looking for medicines in insects that can be used to fight human diseases is:

Chemical prospecting

Chronic toxicity refers to which of the following?

Chronic toxicity refers to a longer exposure to a chemical with adverse effects that appear much later, sometimes even years after the exposure.

Which of the following insects do NOT pollinate plants?

Cockroaches Cockroaches are not insect pollinators. Bees and wasps (Hymenoptera), flies (Diptera), butterflies and moths (Lepidoptera) and beetles (Coleoptera) are all insect pollinators.

Insects are useful in solving crimes, particularly the time of death, because of their natural role in

Decomposition

Which of the following is a reason why alternative food crops that grow around the world are not used today?

Early civilizations that used these plants were conquered and told to plant other crops that their conquerors brought with them

When considering natural ecosystems all over the world, overall, it is a good thing when normal population levels of insects feed on living plants (herbivory) for all of the reasons below except

Eating all of the flowers keeps the trees from producing too many seeds

The white line labeled C in the picture above represents the

Economic Injury Level (EIL)

A field of corn is not an ecosystem because humans created it by clearing the land, plowing the soil, and planting the corn seeds.

False

All insecticides need to be eaten in order to be effective against pests

False

All plants require pollination by animals.

False

An insecticide labeled with the signal word 'Danger' means that insecticide is LESS toxic than another insecticide labeled with the signal word 'Warning'.

False

Biodiversity is all of the different kinds of living things (or the number of species).

False

Biological control is a relatively quick strategy to control a pest and will work for all pest species.

False

Biological control is effective against migratory insects.

False

Cross-pollination occurs between different flowers on the same plant.

False

In developed countries like the United States where most of the earth's biodiversity occurs, it is easier to protect biodiversity because of governmental policies.

False

In general virtually any insecticide can be used against any pest insect as long as you follow the direction for application.

False

Insect decomposers are vital to ecosystems because they feed on all living parts of plants, which stimulates photosynthesis and allow plant material to move to the soil.

False

Integrated pest management is used only in forests and on farms.

False

It only takes 2-3 months for a pesticide manufacturer to discover and register a new insecticide.

False

LD50 is the measure of toxicity and is defined as the number of test animals that die under experimental conditions from 50% of the normal usage dose of the chemical.

False

Pollination is the transfer of pollen from the female part to the male part of the flower.

False

Most of the crops consumed by humans are pollinated by insects.

False Actually, most of the crops used to feed the world are pollinated by wind or are asexual.

Biological control includes the use of chemical pesticides.

False Biological control includes use of parasites, predators, and microbials, but not the use of chemical pesticides.

Heavy, sticky pollen causes allergies.

False Heavy, sticky pollen grains fall to the ground fairly quickly compared to light pollen grains. The light pollen grains become air-borne, and are more likely to be inhaled and cause allergies.

Mites of honey bees are responsible for a decline only in wild honey bee hives.

False Honey bee mites have devastated wild bee hives, and even with management only 50 percent of kept hives survive mite infestations.

A high LD50 means high toxicity.

False If a compound has a low LD50, then you need less chemical to cause a 50% mortality in the organism tested,and therefore you have higher toxicity.

Biological control works well in any situation.

False If you had cockroaches in your home, you probably would not want to release big, hairy wolf spiders inside to take care of the cockroaches, would you? On the other hand, some people might not mind having geckos running about the house to control insect pests!

Predators and parasitoids are a cheap and easy way to control all pest insects.

False In general producing and releasing natural enemies can be complex and expensive. However, if successful predators and parasitoids are environmentally sound and can provide long-term control of pests.

Bee mites injure bee colonies by eating the stored honey.

False Just in case you did not know, there is a greater wax moth whose caterpillar does eat the wax comb of a bee hive. Greater wax moths can be a pest of hives, but the damage they cause is much less than the damaged caused by bee mites.

Nectar guides direct an insect out of a flower.

False Nectar guides would not be very helpful in pollination if they directed pollinators away from the nectaries (and where the insect is likely to come into contact with the pollen)!

Biocontrol uses more predators than parasitoids to control specific pests.

False Parasitoids attack specific pests while predators are usually less picky, attacking any organism small enough to eat. While predators are good to have around, their feeding habits are usually too general to achieve complete control of a pest.

Pesticide resistance is no longer an important issue regarding the use of pesticides.

False Pesticide resistance is of real concern because recommended doses of the pesticide no longer are effective in killing the target organism.

Integrated pest management programs do not require sampling.

False Sampling allows for the proper timing of treatment, which means less money is required to control a pest, there is less ecological disturbance, and in the long run less work is need to manage the crop.

The ovary in plants is part of the female structure of a flower and is the source of pollen.

False The ovary is part of the female structure of a flower but the anthers, or male structures, are the source of pollen. Ovaries produce seed.

The peak labeled "B" on the graph above represents the best time to treat for the pest.

False The yellow line represents the population of a pest, and at "B" the pest has exceeded the Economic Threshold (ET), so economic damage to the crop has already occurred and profits have been lost.

Varroa mites are internal parasites of honey bees.

False Varroa mites are external parasites of honey bees.

Biocontrol works best against native species of insects.

False We use biocontrol against exotic species of insects which have arrived in the United States without the predators and parasites which attack it in its home country. The predators and parasites already here in the U.S. did not evolve to deal with these exotic invaders, so there is little to control the invader's spread. Entomologists often go to the home country of the pest to bring its parasites to the U.S. to release to control the introduced pest. This is referred to as "classical biological control".

Despite years of insecticide manufacturing and use, only a few insect species have developed resistance.

False Yes, we are now approaching 600 or so insect pests that are resistant to different insecticides.

Agricultural crops that require insect pollination are pollinated only by wild bees.

False managed honey bees are moved into crops to pollinate them. Wild bees may contribute to the pollination, but most farmers are dependent on managed hives to pollinate their crops.

The Winged Bean of New Guinea is a good example of an alternative food crop that is presently underused, but it could help feed the world's population. All of the following are reasons why this would be a good crop, except:

It contains a natural insecticide that keeps it from being eaten by insects.

Africanized honey bee (Apis mellifera scutellata) represents an example of introducing a species into a new area without knowing more about its behavior and potential success in the area. What is one of the biggest concerns surrounding Apis mellifera scutellata?

It poses a public safety risk because it is so aggressive

-Which of the following statements about the organochlorine insecticide DDT is NOT true?:

Kills only the target pest

Integrated pest management (IPM) involves all of the following except:

Knowing how many of the pest will be harvested as a source of protein for humans

Useful information about medicines in insects is often discovered by studying local cultures around the world. An recent example of a useful insect medicine that was discovered this way is:

People in China brewing a drink similar to tea from ants to relieve arthritis

If you are implementing an integrated pest management program (IPM) program against an insect pest, the final component that you would put into effect is

Post-treatment sampling to check the pest population levels

The knowledge of an insect's life cycle is important. In the video featuring Dr. William Bass from the University of Tennessee, which life stage provided the final evidence in convicting a murder suspect?

Pupa

Insects are important in ecosystems as prey for many predators. Sometimes they are eaten directly; other times they are linked to large predators by one or more steps in the food chain. All of the following vertebrate animals either eat insects or they eat other animals that eat insects, except:

Rabbits

Pesticides are often tested for their toxic effects on:

Rats Standard white rats are the usual test animals for determining the toxic effects of pesticides

What's the big deal about insect-pollinated crops?

They generate over $30 billion a year.

From the list below, what is the most important reason that humans should care about insect biodiversity

They play essential roles in ecosystems, like the jobs of workers in factories

From a global perspective, the greatest threats to biodiversity and the greatest potential for bad effects to human society are from the loss of tropical rain forests. All of the following statements are true about this situation, except:

Tropical rain forests have deep soils that produce high yields of agricultural crops for many years after the trees are removed

According to the 2014 USDA Pesticide Data Survey, almost all domestic food crops have either no detectable residue or residues less than the legal tolerance

True

All of the following are examples of ecosystem services: regulating the amount of oxygen and carbon dioxide in the atmosphere, creating soil, providing wood for houses, and growing cotton for clothes.

True

Anthers are part of the male structure of a flower.

True

Biological control does not include the use of chemical pesticides.

True

Economic threshold refers to the pest density at which controls must be applied to avert economic loss.

True

Forensic entomology is the use of insects and their relatives to establish the time and/or place of a murder or other crime.

True

Geographic distribution of insects can be used to check alibi of a suspect.

True

Honey bees have specialized structures for pollination.

True

In order for an IPM program to be successful, it is necessary to know the life cycle of the pest, the food preference of the pest, and the susceptibility of the pest to various chemical insecticides.

True

In the United States, where there is a higher consumption of fruits and vegetables, pollination by insects is more important than on a worldwide basis where most grains consumed are wind or self-pollinated.

True

Insect-pollinated crops are important for the U.S. economy.

True

LD50 refers to the toxicity of a chemical compound.

True

Nicotine, which has natural poisonous chemicals, is in the Botanical class of insecticides.

True

Pioneering researchers like E.O. Wilson have estimated that half the rainforests will be gone and 10-20% of rain forest species will be extinct by 2022.

True

Plants are pollinated several different ways. Wind and insects are the most important to successful pollination of most plants.

True

Poor pollination results in reduced yields and inferior fruit.

True

The life cycles of certain kinds of colonizing insects is important in determining the precise Post Mortem Interval (PMI), which provides reliable evidence on the time of a person's death.

True

The red line labeled "A" on the graph above represents the Economic Threshold (ET).

True

The roles of insects and related arthropods in ecosystems are so important that at least one expert predicts that if all of them were to disappear, humanity would not last more than a few months.

True

We should protect natural ecosystems and their biodiversity because insects offer a vast new potential for medical research.

True

Flowers are the reproductive part of the plant.

True Flowers produce seeds after pollination. Each seed has the potential to produce a new plant

The microbial pesticide Bacillus thuringiensis (B.t.) must be ingested by an insect in order to be effective.

True For example, the spores of B.t. become active after they have been ingested.

Pollination by insects is mutually beneficial to both the insect and the plant.

True Generally insects benefit from pollinating plants by the pollen and nectar that they obtain. Plants benefit by being pollinated, allowing them to produce seed.

Integrated Pest Management (IPM) is the combination of controls used to keep pests below some damaging level and it emphasizes the most economically and environmentally compatible control methods.

True IPM is a good tool to maximize agricultural profits in an ecologically sound manner.

Integrated pest management uses a combination of control strategies to maintain pest populations below economically damaging levels.

True In integrated pest management, control measures are implemented when the benefit of control (the economic value of the crop) is greater than the cost to control. Pesticides should only be used when necessary.

Integrated pest management includes the use of chemical pesticides.

True Integrated pest management emphasizes non-chemical control of pests, including natural enemies, proper cultural methods, mechanical control, and microbials, but it also uses chemical pesticides.

Insects are important pollinators.

True Many crops including fruits and vegetables depend on insects for pollination.

Pesticide resistance is an important issue regarding the use of pesticides.

True Pesticide resistance is of real concern because recommended doses of the pesticide no longer are effective in killing the target organism.

Using nonchemical controls should be a first-line defense in a control program because they usually cause less impact on ecosystems.

True This is true because most pesticides are nonspecific and will affect many different organisms. Therefore, it is advisable to look to nonchemical controls first and then apply pesticides only when needed.

Parasites are threatening honey bees in the United States.

True Varroa and tracheal mites pose a large threat to honey bee colonies.

Which one of the following persons is recognized as a world's authority on biodiversity?

Wilson

A pest insect's resistance to pesticides is a serious concern. Chances of resistance can be reduced by

a, b, c

Butterflies and moths fall into which category?

accidental pollinators

The basic functional unit in ecology, where biological communities interact with the physical and chemical environment, is called

an ecosystem

Parasitoids are a commonly used biological control. Insect parasitoids

are commonly from the Hymenoptera (wasps and bees) or Diptera (flies)

Based on the LD50, which of the following four compounds is most toxic?Aspirin: LD50 = 750 mg/kg, herbicide Roundup (herbicide): LD50 = 825 mg/kg Terro Ant Killer (borax): LD50 = 5250 mg/kg Super Blaster Aphid Killer: LD50 = 6500 mg/kg.

aspirin A smaller LD50 value means it takes a smaller amount of that substance to kill 50% of a test population. So it is more toxic. Aspirin is the most toxic in this group.

The biological control strategy commonly used against invasive, introduced pests is called

classical biocontrol, where natural enemies from the pest's natural habitat are investigated and released

The multidisciplinary science that deals with protecting the genes, species, and ecosystems that make up the earth's biodiversity is called

conservation biology

The Economic Injury Level of a pest population is considered the break-even point. When pest populations rise above this level

economic losses will occur

When pest populations rise above the Economic Injury Level (EIL)

economic losses will occur

An ecosystem includes all of the following, except

fixed boundaries

Preserving insect biodiversity is important because

insects have important roles or jobs in ecosystems

Rosy Periwinkle, found in Madagascar, should be protected because

it is an example of a native plant that has a unique biochemistry that cures certain cancers

When pest populations reach the Economic Threshold

it is time to think about managing or treating to prevent economic loss

A LD50 of 20 mg/kg body weight is which of the following compared to a LD50 of 120 mg/kg body weight?

less safe

B. t. (Bacillus thuringiensis) and NPV (Nuclear Polyhedrosis Virus) are examples of what kind of control?

microbial

The caterpillar above probably died from what type of biological control method?

microbial spray

Insect growth regulators are a group of insecticides that:

mimic hormones that are naturally produced by insects

Insect growth regulators (IGR) are often used to control insect pests on pets and livestock. This group of insecticides (IGRs):

mimic hormones that are naturally produced by insects.

Dimilin affects chitin production. In insects, this would affect

molting Chitin is a large component of the exoskeleton, and Dimilin makes molting very difficult by inhibiting chitin production.

Which of the following is NOT an example of a natural ecosystem?

orchard

The economic injury level is the:

pest density at which the cost of control equals what you would loose if you did not control the insect pest.

Certain plants, like European orchids, have special structures that trick insects into helping the plant with pollination. Which of the following is a way a plant deceives insects into visiting the pollen structures?

plant lures males to copulate with pollen structures that look like a female of the insect species

A major difference between insect predators and parasitoids is:

predators are generalists and parasitoids usually are species specific

An LD50 is:

the lethal dose that kills one-half of a population of test organisms, and is measured in mg of product per kg of body weight.

The greatest benefit from honey bee colonies is

the pollination of valuable food crops

What is pollination?

the transfer of pollen from the male part of a flower to the female part of another flower

The consumption of insects in the U.S. is simply a novelty. But, in some undeveloped countries insects are important as food because

they are an important source of protein

What are the dark purple markings on the flowers below and what purpose do they serve?

they are nectar guides to steer pollinating insects towards the nectaries The purple markings are nectar guides which help steer insects towards the nectaries.

The use of Genetically Modified (GM) Crops is a relatively new concept. The advantage of GM Cops is

they have "built in" insecticides

Pollination is:

transfer of pollen from the male part of flowers to female parts.

There is a prosperous industry in the U.S. centered on the ability of insects, like honey bees, to pollinate crops. This industry includes

transporting vast numbers of pollinating insects to the crops and allowing them to pollinate before moving on to the next crop