BIO 262 EXAM 2 Practice Questions
1. A model aimed at characterizing life history traits of plants was developed to include three extremes in terms of plant life history. The extremes were essentially based on ability of plants to channel _____ towards stress, growth and competition. a. Energy b. Offspring c. Evolution d. Mating systems
a
1. Which bests describes a population? a. Individuals of the same species confined within a spatial boundary b. The largest group of organisms capable of reproducing c. The total gene pool of a group of individuals d. A group of similar or nearly identical individuals
a
10. True or false? Polygyny is more likely to occur as differences in territory quality increase between territorial males a. True b. False
a
12. The number of individuals of a species that can be sustained in a given space is the _____ of a population. a. Carrying capacity c. Intrinsic rate of increase b. Gene pool d. Geometric maximum
a
13. A trade-off for having many offspring would be a. that they would likely be small in size. b. that they would likely be large in size. c. that they would require a large amount of parental care. d. that they would have high survivorship.
a
13. Success in managing natural population require: I. Knowing the size, structure and growth patterns of a population II. Determining the MVP (Minimum Viable Population) and MDA (Minimum Dynamic Area) III. The intactness of surrounding areas a. I and II b. I and III c. I,II and III d. I
a
14. An organism's life history is best defined as a. the adaptations of an organism that influence aspects of its biology, such as the number of offspring it produces, its survival, and its size and age at reproductive maturity. b. a combination of the structure and growth dynamics of an organism. c. a situation in which a species establishing itself in greater numbers in a place before the establishment of potential competitors wins in competition with species arriving later. d. the relationship between climate and the timing of ecological events such as the date of arrival of migratory birds or the onset and ending of leaf fall in a deciduous forest.
a
14. Bacteria are capable of rapid growth under ideal conditions. Assuming that a Staphylococcus population is growing exponentially with r = 1.386 h-1, what is the doubling time for the Staphylococcus population? Hint: Set Nt / N0 = 2 a. 0.5 h b. 1 h c. 2 h d. 5.3 h e. 16 h
a
18. If 60 snow geese were alive in 1926 and 856 existed in 2001, what is r? a. 0.035 b. 0.094 c. 0.070 d. −0.050
a
4. A fecundity table is constructed for a gray squirrel as follows. ________________________ x lx mx lxmx 0 1.0 0.0 0.00 1 0.3 2.0 0.60 2 0.15 3.0 0.45 3 0.09 3.0 0.27 4 0.04 2.0 0.08 5 0.01 0.0 0.00 On the basis of these calculations, the net reproductive rate (R0) is equal to a. 1.4. b. 1.59. c. 10. d. 15.
a
5. A model proposed by Grime's aiming at characterizing life history traits of plants focuses attention on: a. stress and disturbance b. stress and nutrient availability. c. disturbance and gene flow d. disturbance and plant species diversity e. r- vs. K-selection
a
5. Using the life table from the previous question, how would you describe the population dynamics? a. The population is increasing. b. The population is decreasing. c. The population is stable. d. Not enough information to conclude.
a
6. As part of your job you are asked to estimate the population of fish in a lake. Based on your extensive knowledge of ecology you approach this question by catching 100 fish in initial sampling and tagging each fish. You return a few weeks later for a second sampling where you again captured 100 fish, 10 of which were tagged and 90 of which were untagged. Your estimate for the population of fish in the lake is: a. 1000 b. 900 c. 450 d. 10,000
a
6. True or False? The instantaneous per capita rate of growth (r) of a growing population is greater than zero. a. True b. False
a
7. True or False? The introduction of a novel organism into an ecosystem can lead to the extinction of species. a. True b. False
a
8. Which of the following groups would be most likely to exhibit uniform dispersion? a. red squirrels, which actively defend territories b. cattails, which grow primarily at edges of lakes and streams c. dwarf mistletoes, which parasitize particular species of forest tree d. moths, in a city at night e. lake trout, which seek out cold, deep water high in dissolved oxygen
a
9. True or False? Extrinsic ecological factors such as the physical environment and the presence of predators or competitors influence age specific rates of mortality and survivorship. a. True b. False
a
One benefit of asexual reproduction is: A it produces young that are likely to survive and reproduce themselves as their parents did B asexual reproduction ensures that the species will never go extinct because no mutations can occur C asexual reproduction ensures that a species will never go extinct because the recombination of genetic material that results from sexual activity does not occur D there is no advantage in reproducing asexually
a
Which of the following is NOT an assumption of the geometric growth equation? A Reproduction can (and does) occur continuously. B Population growth is discrete. C The growth rate is constant. D Age structure of the population can be ignored.
a
Why do populations grow more slowly as they approach their carrying capacity? a. Density-dependent factors lead to fewer births and increased mortality. b. Density-independent factors lead to fewer births and increased mortality. c. Hormonal changes promote higher death rates in crowded populations. d. Individuals voluntarily stop mating so that overcrowding does not occur. e. The incoming energy decreases in populations experiencing a high rate of increase.
a
11. True or False? Species that are r-strategists are usually larger than those that are K-strategists. a. True b. False
b
11. Which of the following could be a density-independent factor limiting human population growth? a. Ebola infections b. earthquakes c. epidemic of measles d. famines
b
16. Under the exponential model, how does the population growth rate (dN/dt) vary with population size (Nt)? a. b. c. d. e.
b
16. Which of the following populations probably exhibits exponential growth? a. a protozoan population grown in a sealed glass culture flask b. a fruit fly population that recently arrived on a lush mid-oceanic island previously inhabited only by plants c. a redwood tree population in a forest d. a population of deer in an area with few palatable food plants e. a population of deer in an area with many hungry wolves
b
20. As N approaches K for a certain population, which of the following is predicted by the logistic growth equation: a. The growth rate will not change. b. The growth rate will approach zero c. The population will increase exponentially d. The carrying capacity of the environment will increase.
b
5. If you were asked to estimate the population of a particular species of plant within a field that was several hundred acres in size the most practical method for you to estimate the population size would be: a. Counting all of the individuals c. Mark and recapture b. Plots and subsamples to estimate density d. Any of these
b
6. The total energetic costs of reproduction per unit of time are referred to as an individual's: a. Fecundity b. Reproductive effort c. Reproductive trade-off d. National grid bill.
b
7. Pacific salmon migrate upstream and after breeding, soon die. They are termed a. iteroparous. b. semelparous. c. dioecious. d. monoecious.
b
9. Although not typically the case with wild populations, under circumstances of unlimited resources populations may grow at high a rate described by: a. A straight line c. A logistic growth curve b. An exponential curve d. A power curve
b
9. Which of the following terms defines an organism's lifetime pattern of growth, development, maturation, reproduction and survival? a. survivorship b. life history c. trade-off d. demography
b
Which of the following is associated with asexual reproduction? A hermaphrodites B parthenogenesis C monoecious hermaphrodites D monogamy
b
2. Populations that pass through several generations rapidly and then disappear have characteristics that would fit with organisms described as having ____ life histories. a. Competitive c. Stress tolerating b. r-selected d. K-selected
b r-selected species example:weeds that colonize vacant habitat, passes through several generations rapidly, produces huge numbers of small seeds, then disappears, eventually displaced by k species with better competitive abilities.
11. Even though populations have the potential to grow at a rate described in the question above there are both biotic and abiotic factors that limit the growth of populations. These factors are referred to as: a. Decreasing factors c. Environmental resistance b. Growth regulators d. Limiting factors
c
12. A life history model that illustrates extremes in reproductive trade-offs, or in other words a balance between reproductive characteristics that result in fast population growth and characteristics that result in slow population growth is: a. Stress tolerators and ruderals c. r and K selected life histories b. Opportunistic and equilibrium d. Fast vs slow reproducers
c
13. The rate at which a population could grow under conditions of unlimited resources varies widely among organisms and is called the _______. a. Carrying capacity c. Intrinsic rate of increase b. Gene pool d. Geometric maximum
c
15. Among fish species, an "opportunistic" life history is characterized by a. high juvenile survival, large numbers of offspring, and early maturity. b. high juvenile survival, large numbers of offspring, and late maturity. c. low juvenile survival, low number of offspring, and early maturity. d. traits that maximize colonizing ability for environments that do not vary much in time or space. e. traits that maximize colonizing ability for environments that are very stressful.
c
17. Biologists studying the reproductive behavior of bluegills (a species of fish) learn that a single female in one breeding season can produce between 1,000 and 70,000 eggs. The life table of these bluegills would fit which of the following descriptions? a. Survival of most offspring until late adulthood and a Type I survivorship curve b. low mortality at birth, then a steep increase in mortality and a Type I survivorship curve c. high mortality early in life and a Type III survivorship curve d. a steady, even decline in the number of survivors throughout the life span and a Type II survivorship curve
c
2. The distribution of a population or essentially where it occurs is referred to as the ______ of the population. a. Boundaries c. Geographic range b. Biological scale d. Species habitat
c
21. A population is growing exponentially and its instantaneous growth rate (r) is 0.02. Would the number of individuals added to the population (rN) be greatest at a population size (N) of 20, 500 or 1000? a. 20 b. 500 c. 1000
c
3. One characteristic that describes the structure of populations is their dispersion. Dispersion describes: a. The number of species with which the population interacts b. How individuals within the population move about c. The pattern of spacing of individuals within a population d. Their pattern of reproduction
c
8. Emigration is a term that applies to populations and is one of the ways in which populations change. Emigration refers to: a. The number of individuals in the population that die b. The number of new individuals that enter an area c. The number of individuals that leave a population d. The number of individuals that are born within a specific time period
c
An individual with a large, high quality territory is likely to have: A a reduced number of offspring B decreased male-male interactions C increased mating success D reduced resources
c
Why can't a female lizard have both high fecundity and high survival? A Female lizards are able to produce only one set of offspring. B Competition for resources prevents this. C The more energy the female devotes to offspring, the less that can be devoted to her survival. D The female is already maximizing the number of eggs she lays, and if she attempts to nest later in the season, there will not be enough food for her young.
c
You observe two female fish from different species breeding. One female lays 100 eggs and the other female lays 10000 eggs. Which of the following is LEAST likely, given the limits of fitness trade-offs? A The female laying 100 eggs breeds more often than the female laying 10000 eggs. B The female laying 100 eggs lives longer than the female laying 10000 eggs. C The female laying 10000 eggs is larger than the female laying 100 eggs. D The eggs from the female laying 10000 eggs have larger yolks than the yolks of the eggs from the female laying 100 eggs.
c and d
12. Which of the following have an impact on decisions about humans mitigating the extinctions and damages to populations? I. Moral issues II. Economic problems III. Health problems a. I and II only b. II and III only c. III only d. I, II, and III
d
18. Which of the following describes the life history of a K-selected organism? a. A female frog produces more than a thousand eggs each year. b. Fireweed spreads quickly into a portion of a forest that has recently been burned. c. Young members of a population experience high predation. d. A mother elephant spends several years protecting her baby.
d
2. Which model of population growth would you employ if reproduction occurs in discrete time periods rather than being continuous? a. exponential b. reciprocal c. logarithmic d. geometric d
d
22. A population of animals in a specific environment with a carrying capacity of 2500 has an r of 1.0 per individual per year and exhibits logistic growth. Considering a population size of 750 individuals, by how many individuals is the population increasing per year? a. 1 b. 2500 c. 1750 d. 525
d
3. Although there are a number of features of the life history of a plant or animal, the majority of life history characteristics are related to: a. Stress c. Growth c. Homeostasis d. Reproduction
d
4. There are a number of characteristics of a population besides the number of individuals that make up the population. Aspects of how the population is structured or in other words the demographics of the population includes description of: a. The sex ratio of males to females b. The proportion of mature individuals for each sex c. The proportion of individuals within different age groups d. All of these
d
4. Which is NOT a characteristic associated with a K-selection life history strategy? a. Slow development c. Late maturity b. Few large young d. Single reproductive event
d
7. Although many populations are stable, they are not normally permanently the same exact number of individuals, but rather increase and decrease over time. Changes in population size are mainly due to: a. Births b. Deaths c. Dispersal d. All of these
d
8. An r-strategist is characterized by a. slow population growth. b. a slow rate of development. c. a long life expectancy. d. density-independent mortality.
d
A sexual system where a male gorilla mates with several females, forming pair bonds with each of them, is called: A promiscuity B monogamy C polyandry D polygyny
d
An advantage to sexual reproduction is: A that there is no need to find a mate. B the potential for high population growth. C that offspring are adapted to the local environment. D increased genetic variability.
d
Bacteria are capable of rapid growth under ideal conditions.Assume:Staphylococcus grow exponentiallyr = 1.386 h-1Initial inoculation = 2 cellsHow many cells will there be after 12 hours? A ~ 90 cells B ~ 96 cells C ~ 451,000 cells D ~ 33,400,000 cells E ~ 8.57 x 1016 cells
d
1. Calculate the generation time given the following population data: R0 = 0.601, r = - 0.05, ∑xlxmx = 6.4, mx = 0.96 a. -128 b. 0.15 c. 1.60 d. 6.67 e. 10.6
e
