IB Bio II semester 1 final 2018
contrast top-down and bottom up limiting factors that can affect population growth, using examples in your answer.
Top down limitng factors: pressures applied by organisms at higher trophic fields Example: Key stone species, such as wolves ~when introduced to Yellowstone National Park, wolves were able to stop the deer from monopolizing and ruining the vegetation. The wolves controlled the deer and, in turn, led the deer to avoid vegetation. This allowed forests to regenerate. Bottom up: applied pressures limiting the availability of lower trophic levels example: nutrients ~When fertilizer gets into the water, the algae absorbs the water. This results in an increase in the number of algae, or algae blooms. This causes the algae to block off sunlight and prevents photosynthesis from occuring in lower trophic levels.
About __________ different species have been described and named to date. : a. 1.75 million b. 160,000 c. 6.25 million d. 265,000 e. 750,000
a
How are the exponential and transitional phases of logistic/sigmoidal growth similar? a. A population is increasing, moving toward its carrying capacity during both phases. b. The emigration rate is higher than the immigration rate during both phases. c. The death rate is higher than the birth rate during both phases. d. A population is at its carrying capacity during both phases.
a
If natality is slightly larger than mortality, and immigration is much larger than emigration, what will happen to the size of a population? a. It will increase b. It will decrease c. It will fluctuate up and down d. It will remain constant
a
Something that controls the growth or size of a population is a a. limiting factor. b. growth factor. c. limiting nutrient. d. carrying capacity.
a
The diagram below is a simplified version of a food web from Chesapeake Bay. The arrows indicate the direction of energy flow and the numbers indicate species within the food web. At which trophic level or levels does species II function? a. 2nd and 3rd consumer b. 3rd consumer c. 3rd and 4th consumer d. Producer
a
The figure below shows a simplified model of the carbon cycle. Each arrow represents a process which involves a transfer of carbon. What are processes X, Y and Z? A. x= Combustion y=Respiration z=Photosynthesis B. x= Fossilisation y= Combustion z= Respiration C. x= Fossilisation y= Respiration z= Combustion D. x= Combustion y= Assimilation z= Photosynthesis a. A b. B c. C d. D
a
The various growth phases through which most populations go are represented on a. a logistic growth curve. b. a population curve. c. an exponential growth curve. d. a normal curve.
a
To date, humans have interfered with all of the biogeochemical cycles on Earth, but this interference has been of the greatest magnitude, in terms of human-induced changes in climate, in the: a. carbon cycle. b. sulfur cycle. c. nitrogen cycle. d. hydrologic cycle. e. phosphorus cycle
a
Using the same key (21) as in the previous question, which of the organisms would be from the phylum Porifera? a. Specimen A b. Specimen B c. Specimen C d. Specimen D
a
What are the main sources of carbon dioxide on earth? a. Cellular respiration of consumers, producers and combustion of fossil fuels b. Photosynthesis and cellular respiration of consumers c. Cellular respiration of producers and combustion of fossil fuels d. Photosynthesis and combustion of fossil fuels
a
What is an advantage of estimating plant populations by random sampling using quadrats? a. Accurate estimates can be obtained more quickly than if every plant in the population is counted. b. Random samples can be taken from the most convenient parts of the habitat. c. Numbers of plants in each quadrat can be estimated quickly. d. Marking and recapture of plants is not necessary.
a
What is the classification of an organism that is able to make organic compounds from inorganic nutrients? a. Autotroph b. Consumer c. Detritivore d. Saprotroph
a
What kingdom includes organisms that are multicellular, eukaryotic, and heterotrophic? a. Animalia b. Archaebacteria c. Plantae : d. Eubacteria
a
Which biome is usually found adjacent to ice-caps? a. Tundra b. Grassland c. Tropical rain forest d. Temperate forest
a
Which is the main reservoir of nitrogen? a. The atmosphere b. Forests c. Ice-caps d. Freshwater
a
Which of the following groups of organisms can convert ammonium and nitrate ions into amino acids? a. Producers b. Primary consumers c. Decomposers d. Top carnivores
a
Which of the following might show primary succession? a. A rock surface exposed by a retreating glacier b. An abandoned farm c. A forest that has been clear-cut d. A newly restored ecosystem
a
Which of the following processes plays an important role in the phosphorous cycle? a. erosion b. combustion c. transpiration d. cell respiration e. evaporation
a
Which property of a gas means that it is classed as a greenhouse gas? a. They trap some of the long-wave radiation emitted by the Earth's surface. b. They prevent sunlight from reaching the Earth's surface. c. They dissolve in rainwater to produce acid rain. d. They are only produced by human activity.
a
he diagram below is a simplified version of a food web from Chesapeake Bay. The arrows indicate the direction of energy flow and the numbers indicate species within the food web. Which of the species feed both as secondary consumers and as tertiary consumers? a. I, II and IV only b. I, III and V only c. I, IV and V only d. III, IV and V only
a
1. The most diverse of the plant phyla. This phylum includes all types of flowering plants. 2. Cone-bearing plants with needle like leaves 3. Organisms with hair, mammary glands, and four-chambered hearts 4. Plants that use spores for reproduction. Ferns are a part of this phylum 5. Organisms with feathers, backbones and are warm-blooded
1. Angiospermophyta 2. Coniferophyta 3. Mammals 4. Filincinophyta 5.Birds
11. Flatworms. Many are parasites. 12. The most divers of the animal phyla. These organisms have hard exoskeletons, segmented bodies, and jointed appendages. 13. The simplest animals. They are sedimentary filter feeders. Sea sponges are a part of this phylum. 14. Organisms with bilateral symmetry and a head and foot region. Many have a shell. This phylum includes snails, clams, and oysters. 15. Plants with not true leaves or roots. Low growing, require water for reproduction.
11. Platyhelminthes 12.Arthropoda 13. Porifera 14. Mollusca 15. Bryophyta
6. Cold-blooded organisms without scales. Gas exanchange can take place through the skin. Live part of their lives in water and part on land. 7. Segmented worms 8. Cold-blooded organisms with bodies covered in scales 9. Aquatic organisms with radial symmetry. They have stinging tentacles which catch prey. Jellyfish and sea anemone are a part of this phylum. 10. Phylum of animals that have a backbone. Includes all species that would be considered vertebrates.
6. Amphibians 7. Annelida 8. Reptiles 9. Cnidaria 10. Chordata
Define the term Keystone Species and describe a specific example.
A Keystone Species is an organism that exerts top-down influence on lower trophic levels in order to stop the lower trophic levels from monopolizing. An example of a Keystone species is a sea otter. Sea otters exert top-down influence by regulating the population of sea urchins. By doing so, they can prevent the sea urchins from monopolizing the kelp which will help kelp remain a habitat for other organisms.
The predominant source of phosphorus is rock containing phosphate (phosphate rock). The graph below shows the world production between 1900 and 2009. Some scientists estimate that available phosphorus reserves in the Earth will be completely depleted within approximately 100 years. Discuss the implications of these estimates.
According to the graph, evident increases in phosphorus have occurred over the last forty years. This is due to humans interfering with the carbon cycle. As a result of this human interference, phosphate in rocks is being mined at a rate that's quicker than natural rock is forming. By continuously mining a nutrient that is already limited, to begin with, humans are contributing, if not the main cause, of the depletion of phosphorus reserves. Alongside, the turnover rate of phosphorus, which is already slow, has the potential to decrease even more due to the decreasing amounts of reserves available. The production of fertilizer has caused the phosphorus cycle to jump from sink to sink through the use of importation/ exportation of crops. If humans keep interfering with the phosphorus cycle by mining, producing/ applying fertilizers, and decreasing the turnover rate of phosphorus then the implications of doing so are arguably inevitable.
Explain how an increase in atmospheric carbon dioxide leads to ocean acidification and why this is a threat to coral reefs.
An increase in atmospheric carbon dioxide leads to an increase in the amount of atmospheric CO2 that is being dissolved in oceans. As the CO2 dissolves, it produces carbonic acid which in turn decreases the pH of the ocean water. Alongside, as bicarbonate and carbonate ions form, H+ ions are released, which also contribute to lowering the pH of water. This poses a threat to coral reefs because, as the pH of water decreases, the acidity of the ocean water increases. By 2100, the coral reefs are estimated to erode faster than they are being built. This threatens the coral reefs' ability to serve as a habitat for other organisms and destructs the growth of these ecosystems.
Describe the role of bacteria in the Nitrogen Cycle.
Bacteria play a major role in circulating nitrogen throughout the cycle. Plants cannot assimilate nitrogen from the atmosphere without the help of bacteria. Nitrogen-fixing bacteria play an important role in converting nitrogen gas into ammonia in the soil through a process called nitrogen fixation. Next, nitrifying bacteria convert ammonia into nitrites and then into nitrates in aerobic conditions through nitrification so that the nitrate can be assimilated into plants. The nitrogen then moves through the cycle by animals, which eat the plant, and decomposers, which decompose the organic matter. Finally, denitrifying bacteria convert nitrates back into nitrogen gas in the atmosphere through a process called denitrification. this is important in restoring balance in the ecosystem.
ist the common name, order, and genus name for a plant species of your choosing.
Common Name: Acer rubrum Order: spinadales Genus: Acer
Which diagram shows the flow of energy through a community with three trophic levels? (#14 on unit 4 test) a. A b. B c. C d. D
D
Organize the following terms to represent the human classifcation scheme from the domain to the species name. The largest taxonomic category should be listed on the top and the smallest on the bottom.
D. eukarya K. animalia P. chordata C. Mammalia O. primate F. hominidae G. homo S. sapien
Describe the main differences between primary and secondary succession.
Primary succession is the emergence of an entirely new ecosystem while secondary succession is the replacement of one ecosystem with another following environmental change. In primary succession, a new ecosystem can be found when a volcano erupts and creates rock formation, resulting in an island. Pioneer species can inhabit this island and help build the ecosystem. Meanwhile, an example of secondary succession would be a fire burning down a deciduous forest. While the forest is burned and the soil is dehydrated, there is still some soil that remains. From that soil, the grass is able to grow. Eventually, trees begin to grow as well, outcompeting the grass. From there, more species begin to grow until a climax population is reached.
Describe the major characteristics of a eutrophic lake.
a eutrophic lake is a lake that has an increase in nutrients due to leaching that has occurred. This causes a decrease in water transparency and increases potential toxins. Alongside, plants, like algae, that are typically waiting for nutrients start to grow at an alarmingly quick rate due to the abundance of nutrient in the lake. As a result, algae blooms form and block out the sunlight from reaching lower trophic levels. This, in turn, decreases biodiversity in the lake. In order to decompose the algae, bacteria utilize a large amount of oxygen, reducing the oxygen levels available to other organisms. As a result, this may result in dead zones as well as an increase in the death of oxygen-dependent organisms.
A disease resulting in the deaths of one third of a dense population of bats in a cave would be a a. result of exponential growth. b. density-dependent limiting factor. c. nutrient-limiting factor. d. density-independent limiting factor.
b
An example of a population is a. all animals in a forest. b. all maple trees in a forest. c. all trees in a forest. d. all plants in a forest.
b
Below is the diagram of the nitrogen cycle. (# 12 on unit 5 test) Denitrification is a. I b. II c. III d. IV
b
Carbon cycles through the biosphere in all of the following processes EXCEPT a. photosynthesis. b. transpiration. c. burning of fossil fuels. d. decomposition of plants and animals
b
Closely related or similar genera are grouped into a single: a. class. b. family. c. phylum. d. order. e. species.
b
In ecosystems the amount of energy that passes from one trophic level to the next is called the conversion efficiency. What is the average conversion efficiency from primary to secondary consumers in most ecosystems? a. 1% b. 10% c. 50% d. 90%
b
The capture-mark-release-recapture method was used to determine the number of Sandhill Cranes (Grus canadensis nesiotes), an endangered species of bird, living on an island. The following data were obtained: · number of Sandhill Cranes initially caught, marked and released = 22 · total number of Sandhill Cranes caught in second sample = 14 · number of marked Sandhill Cranes in the second sample = 2 What is the population size of the Sandhill Cranes on the island? a. 77 b. 154 c. 308 d. 616
b
The diagram below shows some of the storages and flows in the nitrogen cycle. Which processes can be represented by flows I and II? (#14 on unit 5 test) A. i. Respiration II. Manufacture of fertilizers B. I. Denitrification by anaerobic bacteria II. Fixation of nitrogen by lightning C. I. Fixation of nitrogen by lightning II. Photosynthesis D. I. Nitrification by aerobic bacteria II. fixation of nitrogen by lightning a. A b. B c. C d. D
b
The graphs below represent the average monthly precipitation and temperature in two biomes. Which of the following correctly identifies biomes X and Y? A. x= Temperate forest y= Tundra B. x= Tropical rainforest y Tundra C. x= Tropical rainforest y= Desert D. x=Temperate forest y=Desert a. A b. B c. C d. D
b
The movement of organisms into a range is called a. carrying capacity. b. immigration. c. population shift. d. emigration.
b
The t-test is used to test the statistical significance of a difference. What is that difference? a. Between observed and expected results b. Between the means of two samples c. Between the standard deviation of two samples : d. Between the size of two samples
b
What do error bars on graphs show? a. If the data is correct or not b. how variable the data is c. Which result is closest to the true result. d. What statistical technique was used to eliminate incorrect results.
b
What is the role of the Arctic hare? a. Detritivore b. Primary c. Secondary Consumer d. SaprotrophConsumer
b
What is the significance of bacteria found in the root nodules of legumes? a. They carry out photosynthesis. b. They provide fixed nitrogen to legumes. c. They provide fixed carbon dioxide to legumes. d. None of the answer choices are correct. e. They carry out respiration.
b
Which classification level would be the least inclusive? a. order b. genus c. class d. family e. phylum
b
Which classification level would contain the greatest number of species? a. class b. domain c. division or phylum d. family e. order
b
Which of the following ecological units includes abiotic factors? a. A community b. An ecosystem c. A populaiton d. A trophic level
b
Which of the following is an example of mutualism? a. Vultures eating a dead antelope b. An insect pollinating an orchid flower c. A caterpillar eating leaves of a fig tree d. A flea living on the skin of a rabbit
b
Which of the following is the best definition of a population? a. A group of individuals that can interbreed and produce fertile offspring b. The number of individuals of the same species in a given area c. A group of species living and interacting with each other in a given area d. The total number of individuals in a given area
b
Which of the following statements describe a "population"? a. All the autotrophs and heterotrophs living in a certain area b. Individuals belonging to the same species in a certain area c. Two geographically isolated groups belonging to the same species d. A group of different species living in the same area at the same time
b
Which statement about the greenhouse effect is true? a. It is a recent phenomenon that started about fifty years ago. b. It is a natural phenomenon caused by several gases. c. . It is a natural phenomenon caused by only carbon dioxide. d. Human activities are the only cause of the effect.
b
Which statement describes the term species? a. Members of the same ecological community b. Organisms that reproduce together to produce fertile offspring c. Organisms of similar type in a population d. The first word in the binomial name of an organism
b
Zea mays is the scientific name of the corn plant. Zea is the ____________ name. a. species b. genus c. division d. ordinal e. class
b
nitrogen is returned to the atmosphere by a. lightning discharges. b. denitrifying bacteria. c. nitrifying bacteria. d. leguminous plants.
b
A collection of four animal specimens is observed and a dichotomous key is applied. Which specimen is an arthropod? 1. Non-segmented body ......................................... go to 2 Segmented body ................................................. go to 3 2. Body is not symmetrical ..................................... specimen A Body is symmetrical ........................................... specimen B 3. Jointed appendages present ................................ specimen C Jointed appendages absent ................................. specimen D a. Specimen A b. Specimen B c. Specimen C d. Specimen D
c
Carbon cycles through the biosphere in all of the following processes EXCEPT a. burning of fossil fuels. b. photosynthesis. c. transpiration d. decomposition of plants and animals
c
Carbon is a major component of all organic compounds, including carbohydrates, lipids, proteins, and nucleic acids. Carbon dioxide is continually exchanged between the atmosphere and oceans. What geological process returns carbon to the atmosphere in the form of carbon dioxide? a. respiration b. transpiration c. volcanic activity d. decomposition of marine organisms
c
Density-independent factors: a. influence population size and are in turn influenced by changes in population density. b. may be the result of intense interspecific competition. c. are typically abiotic. d. may include parasites and diseases. e. None of the above.
c
In a mature forest, the trees are eaten by small primary consumers which are then eaten by much larger secondary consumers. Which of the following pyramids best represent this ecosystem? (#29 on unit 4 test) a. A b. B c. C d. D
c
Net Primary Production is the amount of energy a. produced from 'alternative' sources in developing countries b. fixed in an ecosystem by photosynthesis. c. fixed in an ecosystem by photosynthesis, minus the losses due to respiration by producer organisms. d. fixed by the herbivores in an ecosystem.
c
Slime moulds (Acrasiomycota) are protoctists. They feed on decaying organic matter, bacteria and protozoa. Which of the terms describes their nutrition? I. Detritivore II. Autotroph III. Heterotroph a. I only b. I and II only c. I and III only d. I, II and III
c
The diagram below shows a simplified version of the carbon cycle. What processes are involved in the transfer of carbon at stages I and II? A. I= combustion II= photosynthesis B. I= photosynthesis II= respiration C. I= combustion II= respiration D. I= fossilization II= respiration
c
The graph below represents a sigmoid (S-shaped) population growth curve. Three sections of the curve are indicated (1, 2 and 3). In which of the sections is natality plus immigration greater than mortality plus emigration? 1. graph is increasing 2. still increasing/ getting closer to leveling out 3. graph is leveled out a. 1 only b. 2 only c. 1 and 2 only d. 3 only
c
The graph in Figure 5-3 shows the changes in a mosquito population. What caused the changes seen in the graph? a. a increase in predation. b. a reduction in resources c. a density-independent limiting factor d. a density-dependent limiting factor
c
This nutrient cycle does not have a gaseous phase: a. sulfur cycle. b. hydrologic cycle. c. phosphorus cycle. d. nitrogen cycle. e. carbon cycle.
c
What contributes to the enhanced greenhouse effect? a. Ozone from violent thunderstorms b. Sulfur particles in diesel engine exhaust c. Methane from agricultural sources d. Carbon dioxide from active volcanoes around the world
c
What will happen to the sizes of the populations in the food web above if the sea otter disappears? a. Large fish increase and sea urchins decrease. b. Abalones increase and sharks increase. c. Sea urchins increase and kelps decrease. d. Sea stars decrease and sharks increase.
c
Which factors can limit population growth? I. Shortage of food II. Increased genetic variation in the population III. Increase in predators IV. Increase in diseases and parasites a. I and II only b. I and III only c. I, III and IV only d. I, II, III and IV
c
Which of the following trophic groups include fungi? a. Detritivores b. Autotrophs c. Saprotrophs d. Producers
c
Which statement describes how humans are affecting the balance of carbon in the atmosphere? a. Overgrazing of grasslands has reduced the amount of carbon dioxide in the atmosphere. b. Severe drought in large areas of the world has decreased the amount of carbon dioxide that is released into the atmosphere. c. Burning fossil fuels in great quantities has increased the amount of carbon dioxide in the atmosphere. d. Fewer agricultural crops are planted, reducing the amount of carbon dioxide released into the atmosphere.
c
Why do food chains in an ecosystem rarely contain more than five organisms? a. Nutrients are recycled by the decomposers back to the producers. b. Nutrients are lost from the ecosystem when organisms die. c. The conversion of food into growth by an organism is not very efficient. d. Energy is recycled by the decomposers back to the producers.
c
d on the information in Table 22-01, one characteristic used at the class level of classification for corn is: a. tall annual grasses. b. flowering vascular plants. c. the presence of a single seed leaf d. flower parts in fours or fives. e. separate male and female flowers.
c
the movements of energy and nutrients through living systems are different because a. energy is limited in the biosphere, and nutrients are always available. b. nutrients flow in one direction, and energy recycles.This answer is incorrect. c. energy flows in one direction, and nutrients recycle. d. energy forms chemical compounds, and nutrients are lost as heat.
c
which factors can cause a decrease in a population A. Low emigration High natality Low immigration High mortality B. High emigration Low natality High immigration Low mortality C. High emigration Low natality Low immigration High morality D. Low emigration high natality high immigration low mortality
c
An example of a density-dependent factor that influences the size of a population is: a. rainfall. b. temperature. c. a fire. d. parasites. e. None of the above.
d
Bacteria are found in the Kingdom: a. Animalia. b. Fungi. c. Plantae. d. Eubacteria. e. Protista.
d
If the producer biomass in an ecosystem is 300 kg ha-1, what is the approximate secondary consumer biomass (kg ha-1) likely to be in the same ecosystem? a. 3000 b. 300 c. 30 d. 3
d
Phosphorus is very important for living things because living organisms need phosphorus to a. make carbohydrates. b. cycle energy. c. perform transpiration. d. form DNA and RNA.
d
Plants play a crucial role in the carbon cycle because they a. are chemically converted into fossil fuels when burned. b. have special bacteria that live in their root systems. c. do not release carbon dioxide during cellular respiration. d. allow carbon to enter an ecosystem through photosynthesis.
d
The binomial system of nomenclature is a product of the work of: a. Charles Darwin. b. Gregor Mendel. c. Paul Hebert. d. Carolus Linnaeus. e. Ernst Haeckel.
d
The classification level of domain is immediately "above" (more inclusive than) the level of: a. a genus. b. a class. c. a species. d. a kingdom e. a phylum.
d
The energy available at the tertiary consumers (top carnivores) level in a particular ecosystem is 100 kJ m-2 y-1. How much energy (in kJ m-2 y-1) is likely to available at the producer level in this ecosystem? a. 1 b. 10 c. 1000 d. 10000
d
The following diagram shows part of a food web from Yellowstone Park. aspen- elk, moose, beaver- gray wolf (eats only elk and moose)\ A. Increase beaver Decrease moose Increase elk Increase aspen B. Decrease beaver Decrease moose Decrease elk Decrease apsen C. Increase beaver Increase moose Decrease elk Increase aspen D. Decrease beaver Increase moose Increase elk Decrease aspen a. A b. B c. C d. D
d
This diagram represents a simple food chain. In which ways is energy lost between the trophic levels? I. Heat loss through cell respiration II. Material not consumed III. Material not assimilated a. I and II only b. I and III only c. II and III only d. I, II and III
d
Using Table 22-01, all of the following characteristics are used to establish the family level of classification for corn except: a. grasses with hollow stems. b. fruit is a grain. c. large endosperm in the seed. : d. one seed leaf. e. None of the above, all are used to define the family level of classification for corn.
d
Using the same key (21) as in the previous question, which of the organisms would be from the phylum Annelida? a. Specimen A b. Specimen B c. Specimen C d. Specimen D
d
What is a community? a. A group of organisms living and interacting in the same trophic level b. A group of populations living and interacting in a food chain c. A group of organisms of the same species living and interacting in an ecosystem d. A group of populations living and interacting in an area
d
What is the correct format for the scientific name of an extinct carnivorous dinosaur? a. tyrannosaurus Rex b. Tyrannosaurusrex c. tyrannosaurus rex d. Tyrannosaurus rex e. Tyrannosaurus Rex
d
When writing species names, it is sometimes permissible to abbreviate the _______________ name. : a. species b. order c. class d. genus
d
Which is the best prediction about biomass? a. The biomass of X is more than the biomass of W. b. The biomass of X is less than the biomass of Y. c. The biomass of V + X + Z is equal to the biomass of W. d. The biomass of Y is less than the biomass of Z.
d
Which of the following are greenhouse gases? I. Water Vapor II. Carbon dioxide III. Methane A. I and II only B. I and III only C. II and III only D. I, II and III a. A b. B c. C d. D
d
Which of the following does not contain carbon from the bodies of plants and animals that died millions of years ago? a. natural gas b. coal c. oil d. phosphate salts
d
Which of the following series correctly represents the hierarchical organization within ecology? a. ecosystem ® population ® community ® biosphere b. biosphere ® community ® population ® ecosystem c. community ® population ® ecosystem ® biosphere d. population ® community ® ecosystem ® biosphere e. None of the above.
d
Which of the following statements about succession is/are correct? I. It is initiated by pioneer species. II. It often involves organisms changing the environment so that they are replaced by others. III. It generally results in more complex communities a. I only b. I and III only c. II and III only d. I, II, and III
d
Which of the following terms describe(s) species X? I. Heterotroph II. Primary consumer III. Secondary consumer a. I and II only b. I and III only c. II only d. I, II, and III
d
Which of the following would most likely cause a large number of density-independent deaths in a population? a. predators b. limited resources c. disease-carrying insects d. winter storms
d
dentify the correct statements below concerning the concept of the feed conversion ratio (FCR): I. Feed Conversion Ratio = Mass of Feed/Mass of Biomass Output II. The lower the feed conversion ratio, the more efficient the method of production III. Restricting animal movement tends to increase the value for FCR a. I and II onlyThis is the correct answer. b. I only c. I and III only d. I, II, and III
d
n a pond, two species of fish feed on insects and worms. The insects feed on the green plants that live in the water. What constitutes a population in this ecosystem? a. All the living organisms b. All the animals c. All the fish d. All the fish of one species
d
ore productive because nitrogen-fixing bacteria help to keep away pests. b. less productive because legumes remove phosphorus from the soil. c. less productive because the legumes have already taken all the nitrogen, carbon, and phosphorus from the soil. d. more productive because bacteria living on the roots of legumes fix nitrogen in the soil.
d
As part of the carbon cycle, carbon can be found in all of the following except: a. limestone, animals, and plants. b. oil, bicarbonate, and organic molecules. c. carbon dioxide and coal. d. the atmosphere. e. None of the above, all are sources of carbon for the carbon cycle.
e
Most biologists recognize ___________ domains. a. 12 b. 5 c. 6 d. 4 e. 3
e
Prokaryotic organisms make up the a. Archaebacteria, Eubacteria, and Protists b. Archaebacteria and Protists c. Protists and Eubacteria d. Protists e. Eubacteria and Archaebacteria
e
Taxonomy is the science of: a. conserving biodiversity. b. making new biological species. c. comparing macromolecules to assess evolutionary relationships. d. generating cladograms that represent evolutionary relationships between organisms. e. naming, describing, and classifying organisms.
e
When the size of a population greatly exceeds K, it will typically: a. slowly increase. b. slowly decrease. c. rapidly increase. d. stabilize. e. rapidly decrease.
e
Distinguish between fundamental and realized niches, using a specific example in your answer.
undamental niches are the range of environmental and social conditions in which a species could potentially survive and reproduce. An example of a fundamental niche would be a warbler bird feeding on the whole tree. Meanwhile, a realized niche is the specific set of conditions in which an organism actually survives and reproduces. An example of this would be warblers feeding on a specific part of the tree.
Describe 3 causes of the increase in global average temperatures and 3 potential effects.
One cause of the increase in global average temperature is an increase in the amount of CO2 in the air. This occurs because of combustion which is caused by an increase in the number of fossil fuels burning. A second cause of the increase in global average temperatures is water vapor and the role it plays in the greenhouse effect. Water droplets in clouds retain heat during the day and then reemit the heat back to the surface of the earth during the night. The third cause of an increase in temperature is the increase of methane in the atmosphere due to agriculture and the use of fertilizer. Finally, nitrogen oxide plays a role in the increase of global average temperatures; however, the role they play is not that big because bacteria naturally oxidizes the nitrogen. Because of an increase in these gases in the atmosphere, negative effects arise. The first potential effect is more intense or frequent heatwaves as well as high global average temperatures. The second potential effect is that some areas will become more prone to droughts, rainfall, and flooding. The third potential effect is that tropical rainstorms will become more frequent and powerfu
Describe the role of methanogens in the carbon cycle. Include at least two example habitats in which they can be found in your answer.
Methanogens are archean microorganisms that produce methane as a metabolic byproduct in anoxic conditions. Methanogens first convert organic matter to acid, and then the acid is converted into carbon dioxide. These Archean microorganisms are typically found in wetlands, landfills, marine and fresh sediments, and the digestive tract of animals (humans, cows, termites, etc). These microorganisms function under anaerobic conditions. When carbon dioxide is produced, they release methane as a byproduct. Methane is a greenhouse gas and has contributed to the rise in climate levels.
Compare and contrast the Nitrogen and Phosphorus Cycles. Provide at least 2 similarities and 2 differences.
The nitrogen cycle and phosphorus cycle are similar in the fact that they are two limiting cycles. This is due to the fact that the weathering of rocks in the phosphorus cycle is a slow process. Alongside, the nitrogen cycle is limiting because nitrogen is often easily leached and because nitrogen gas has to be converted to ammonia before being used. However, these cycles are also different; while the nitrogen cycle starts off in the atmosphere, phosphorus is not found in the atmosphere. Instead, phosphates are found in rocks that eventually go through weathering and erosion. Next, the phosphates enter the soil and are assimilated by plants. This is different than the nitrogen cycle because rather than weathering occurring, nitrogen gas is made available to organisms through bacteria. Another difference in these cycles is that human interference plays a bigger role with the phosphorus cycle than it does with the nitrogen cycle. This is because humans mine phosphate in order to create phosphate-based fertilizer. Despite these differences, both producers, consumers, and decomposers play a role in moving both nitrogen and phosphorus through their cycles. Alongside, both of these cycles pave way for possible eutrophication to occur
The data table below shows the nitrogen content of a temperate forest and a tropical forest. Nitrogen / gm-2 (#19 on unit 5) component Leaves Temperate forest: 12.4 Tropical forest: 52.6 component= Wood* temperate forest: 18.5 Tropical forest: 41.2 component Roots Temperate forest: 18.4 Tropical forest: 28.2 component Surface= litter Temperate forest: 40.9 Tropical forest: 3.9 component=soil** Temperate forest: 730.9 Tropical forest: 85.3 Total temperate forest: 821.1 tropical forest: 211.2 In terms of the impact on nitrogen storage, deduce which ecosystem would suffer more from clear-cut forestry practices (complete removal of all tree cover). Explain your answer.
The tropical forest would suffer more because, according to the data table, nitrogen prooves to be more limiting in that biome. While the available nitrogen in the soil of a temperate forest is 730.9 gm-2, the available nitrogen in a tropical forest is only 211.2 gm-2. Clear-cut forestry would further reduce the little amounts of nitrogen that is available.
Name and describe a method for determining the size of fish populations and identify the challenges in conserving world fish stocks.
n the last fifty years, there's been a major decline in the population of fish due to unsustainable fishing practices. The fish are being caught at a rate that is beyond the maximum sustainable yield. As a result, the fish aren't breeding before being caught, resulting in a decrease in the population. One way to estimate the population of the fish is to use a coded wire detector tag. In this method, magnetized, stainless wires are used. A row of numbers on the tag identifies the group of fish. Injectors then cut the tags from the spool and implement them into the fish. This method is beneficial because it has minimal effects on the host, has long retention, and allows one to gather a good amount of data without individual going out and catching the fish. However, this method is typically only used in great lakes because it is too small to be used in the ocean. As a result, it makes it even that much harder to conserve world fishing stocks. As fishing industries keep fishing beyond the maximum sustainable yield, the fish populations are drastically declining. It's often times hard to regulate these industries because they often inaccurately report how much fish they are truly catching. Alongside that, these companies may be catching fish that are restricted from being caught, only worsening the overfishing problem. In some places, governments are not enforcing the laws set in place to regulate fishing. Another major challenge is the fact that these fishing industries are exceeding the recommended amount of fish that should be caught. Scientists recommended an average of 10,000 fish; however, up to 61,000 fish are being caught. Additionally, another challenge would be trying to find a balance between regulating these fishing companies and not having these companies go out of business. While the amount of fish these companies are catching are often times leading to the extinction of fish such as the blue cod, these companies also provide jobs to many. If exclusion zones were to be implemented, then this fishing ban may cause the company to go into a long time recession and leave many unemployed. Since fishing industries continue to catch and inaccurately report their catches without strict government enforcement, the process of conserving world fish stocks will continue to present challenges.
