Monday, June 5, 2000

Final Exam

Biology 114

Name: _____________________________________

ΠPlace your name at the top of each page.

� There are 18 non-comprehensive and 15 comprehensive questions

Ž Each half is worth the same amount, with each question worth the same as the others in its half

� Remember to distinguish compared items by linking descriptions with terms (e.g., the sky is blue).

� Unless requested, do not multiply out expressions (e.g., stop at 2*500³ rather than 2.5x10⁸).

‘ I encourage you to ask questions during the exam, but do so discretely.

’ Remember to use safe, i.e., unambiguous & well-articulated answers whenever possible.

“ Above all, avoid jumping to profoundly incorrect conclusions: make sure you actually read a question (all of it) before you answer, and then make sure you are actually answering what is you are being asked.

(1.1) How are the definitions of “homologous structure” and “vestigial structure” similar and how do they differ?

How are they similar?

How do they differ?

A: A vestigial structure is a homologous structure, i.e., a structure that is in common between two organisms by descent; a vestigial structure, however, has at best a marginal function in the possessing organism whereas homologous structures are simply similar due to common ancestry (i.e., a vestigial structure is no-longer used structure that is similar by descent to a functional structure found in another organism) (Chapter 22)

(1.2) The allele for the hair pattern called "widow's peak" is dominant over the allele for no "widow's peak." In a population of 1,000 individuals, 510 show the dominant phenotype. What number of individuals would you expect for each of the possible genotypes?

A: AA = 90; Aa = 420; aa = 490 ; 1000 – 510 = 490 = 1000* q²; q = 0.7; p = 0.3; p² = 0.09; 2pq = 0.42; 0.09 * 1000 = 90; 0.42 * 1000 = 420 (Chapter 23)

(1.3) Two individuals that live within the same geographical area at the same time but otherwise never meet may be experiencing __________, a kind of prezygotic isolating mechanism.

(a) Geographical isolation

(b) Habitat isolation

(c) Hybrid breakdown

(d) Introgression

(e) Reduced hybrid fertility

A: (b) Habitat isolation (chapter 24)

(1.4) A taxon that includes phenotypically similar descendant species (e.g., members of class Reptilia) but fails to include phenotypically dissimilar species (e.g., members of class Aves) is said to be ___________ and consequently does not define a clade.

A: Paraphyletic (chapter 25)

(1.5) Give a compelling reason for speculating that the earliest forms of cellular life were prokaryotic?

A: (i) Life presumably started out more-simple only to become more-complex with time; prokaryotes have simpler cell structures than eukaryotic cells; (ii) the earliest fossils are of prokaryotes; or (iii) the universal tree has two prokaryotic branches and only a single eukaryotic branch leading to speculation that it is eukaryotic-ness that is the derived trait rather than prokaryotic-ness (chapter 26)

(1.6) What kind of bacterial nutritional pattern would you not expect to find at a deep-sea hydrothermal vent and why not?

A: Phototrophs would not be present at deep-sea thermal vents because they require light for energy (chapter 27)

(1.7) Which of the following kingdoms contains no photosynthetic members?

(a) Archezoa

(b) Chromista

(c) Plantae

(d) Protista

(e) Rhodophyta

A: (a) Archaezoa (chapter 28)

(1.8) What is the ploidy and what specifically is the mitotic product of an Archegonium?

Ploidy:

Mitotic Product:

A: Archegonium are haploid (i.e., part of the gametophyte generation) and they produce the larger of the two gametes, i.e., eggs (chapter 29)

(1.9) How many plant generations are found associated with the embryo-dispersal stage of a flowering plant?

A: Three, the sporophyte grandparent (conspicuous plant), the gametophyte parent that gave rise to the gametes, and the sporophyte embryo the represents the next generation (chapter 30)

(1.10) Other than plants with mychorrizal fungi, with what kind of terrestrial organism (organism loosely defined) does one find hyphae, cyanobacteria, nitrogen fixing, and symbiosis?

A: lichens (chapter 31)

(1.11) The presence of a gut (including separate mouth and anus) is associated with

(a) Annelida

(b) Bilateria

(c) Cnidaria

(d) Gastrulation

(e) Radiata

A: (a) Annelida (chapter 32)

(1.12) Give the common name of a member of each of the following classes:

(a) Bivalvia: __________

(b) Gastropoda: __________

(c) Cephalopoda: __________

A: E.g., (i) clams, (ii) snails, (iii) squids (chapter 33)

(1.13) The Hominoids include ____________________, ____________________, ____________________, ____________________ (give the common or formal names of four members).

A: Gibbons, Orangutans, Gorillas, Chimpanzees, Hominids, Humans, etc. (chapter 34)

(1.14) The ecological study of how the characteristics of individual organisms impact on the ability of those organisms to interact with their environments is called __________ ecology.

(a) Behavoral

(b) Community

(c) Ecosystem

(d) Organismal

(e) Population

A: (d) Organismal (chapter 50)

(1.15) Which of the following—which are means by which cooperative behavior might be selected for—most-directly involves the concept of inclusive fitness?

(a) Avoidance of punishment

(b) Group selection

(c) Kin selection

(d) Optimal foraging

(e) Reciprocal altruism

A: (c) Kin selection (chapter 51)

(2.1) Which nutrient cycle is the most local in its impacts, involves loss from ecosystems mostly by erosion, and may be significantly gained by ecosystems by the movement (including the bowel movement) of animals?

(a) Carbon cycle

(b) Nitrogen cycle

(c) Phosphorous cycle

(d) Water cycle

(e) None of the above

A: (c) Phosphorous cycle (chapter 54)

(2.2) Which is not an interaction between two or more species?

(a) Coevolution

(b) Competitive exclusion

(c) Mutualism

(d) Secondary succession

(e) All are interactions between two or more species

A: (e) All are interactions between two or more species (e.g., secondary succession involves competition between species which is a form or interaction between species); all are concepts considered in your community ecology chapter—since community ecology is the study of interactions between species, the inclusion of a concept in this chapter is a good indication that it involves some kind of interaction between species (chapter 53)

(2.3) What occurs to the size of a population when death rates exceed a population’s fecundity?

A: The population decreases in size (chapter 52)

(2.4) What is interference competition?

A: Interference competition is interspecific competition that involves actual fighting (chapter 53)

(2.5) What essential nutrients (two) typically are found in ecosystems at the lowest concentrations relative to their need by organisms within those ecosystems?

A: Phosphorous and nitrogen, i.e., these typically are the limiting nutrients within an ecosystem (chapter 54)

(2.6) Under what environmental circumstances would you expect a population to grow at its intrinsic rate of population increase?

A: The environment must be ideal including without limits; exponential growth, on the other hand, requires only that population growth is possible (chapter 52)

(2.7) Two general phenomena have the greatest impact on the efficiency with which primary productivity is converted to secondary productivity. The first has to do with the inefficiencies involved in energy transfer in general. The second is the efficiency with which consumers digest and absorb nutrients (assimilation). The third has to do with what additional consumer characteristic?

A: Secondary productivity firstly is a function of the rate of acquisition of nutrients, and secondly is a function of the efficiency with which an organism converts those acquired nutrients into new organism, which is in part a function of metabolic rate, with lower metabolisms resulting in greater secondary productivity and higher metabolisms resulting in lower secondary productivity (all else held constant) (chapter 54)

(2.8) The number of individuals living per unit area within a given geographic range defines a population’s __________.

A: Density (chapter 52)

(2.9) Primary productivity that has been stored by primary producers is called __________.

A: Stored primary productivity we call biomass (chapter 54)

(2.10) Plus-minus interactions between species include all of the following except __________.

(a) Predation

(b) Parasitism

(c) Parasitoidism

(d) Herbivory

(e) Commensalism

A: (e) Commensalism (chapter 53)

(2.11) Intraspecific competition is an example of a density-_________ factor that serves to limit a population’s growth rate.

A: Dependent (chapter 52)

(2.12) In what form does energy tend to leave ecosystems?

A: Energy tends to leave ecosystems dissipated as heat (chapter 54)

(2.13) How do death rates vary from cohort to cohort in type II survivorship?

A: Death rates do not change from cohort to cohort given type II survivorship (chapter 52)

(2.14) How can predation result in an increase in prey diversity?

A: A single predator species can consume various prey without driving any one to extinction since optimal foraging can result in prey caught and consumed as a function of their population densities such that predation maintains prey diversity by frequency-dependent effects in the same manner that frequency-dependent selection can maintain a balanced polymorphism (chapter 53)

(2.15) Draw and label a pyramid of productivity and explain why it is a pyramid.

A: Producers make up the base, followed by primary consumers, followed by secondary consumers, etc. and the shape is a pyramid because of inefficiencies in conversion of primary productivity into secondary productivity as one moves up trophic levels (chapter 54)

(2.16) Contrasting equilibrial species, an opportunistic species is less capable of maintaining its population size at the _________ of the species’ environment.

A: Carrying capacity (chapter 52)

(2.17) Camouflage is an example of __________.

(a) A mechanical defense

(b) Aposematic coloration

(c) Batesian mimicry

(d) Cryptic coloration

(e) Müllerian mimicry

A: (d) Cryptic coloration (chapter 53)

(2.18) A climax community is made up of organisms that are particularly good at reproducing __________.

(a) During primary succession

(b) During secondary succession

(c) In meadows

(d) In the face of interspecific competition

(e) With a high intrinsic growth rate

A: (d) In the face of interspecific competition (chapter 53)