1) Americans use about __________ times as much energy as the world average.
A) 20 B) 1.5 C) 5 D) 10 E) 2
2) Rabbits were introduced to Australia about 100 years ago for the purposes of hunting. They have been multiplying, eating up the native vegetation, and destroying the native habitat of other small animals, ever since. In the 1950s, in order to control the rabbit population, government scientists released the myxomatosis virus. The virus, which dramatically reduced the rabbit population, is an example of
A) a predator.
B) a parasite.
C) the effect of migration on growth.
D) a cyclical pattern of growth.
3) Environmental resistance is a limit imposed on population growth by
A) birth rates.
B) the abiotic environment only.
C) both the biotic and abiotic environment.
D) the biotic environment only (predators, competitors).
E) death rates
4) Which BEST describes the reason for the very rapid growth of the human population in the last 8,000 years?
A) Humans have few offspring but their young survive at a high rate
B) Technology has allowed the species to overcome some environmental resistance.
C) Climatic change has allowed the human species to expand its range.
D) The biotic potential for humans has increased.
E) Environmental resistance does not apply to humans.
5) If similar species each occupy a smaller niche when they live together than they would if they lived alone, they are said to be
A) partitioning resources.
C) increasing niche overlap.
D) involved in succession.
6) Which of the following is NOT likely to characterize pioneer plant species involved in primary succession?
A) produces many small seeds that can travel great distances
B) slow-growing, long-lived perennial
C) able to tolerate low nutrient levels
D) able to tolerate intense sunlight
E) small size
7) In the process called __________ , predator and prey species act as agents of natural selection on each other.
8) Phosphorus, which is very commonly a limiting nutrient in ecosystems, is very important because it
A) evaporates quickly.
B) is found only in sedimentary rocks.
C) is part of the hydrologic cycle.
D) is necessary for the production of cellulose so that autotrophs can grow and provide food for heterotrophs.
E) is needed for molecules such as ATP, cell membranes and nucleic acids.
9) Which best illustrates the movement of energy through an ecosystem?
A) food web
B) trophic chain
C) nutrient cycles
D) biological magnification
E) food chain
10) Which of the following factors is (are) frequently limiting in terrestrial environments?
B) oxygen and nutrients
C) both water and appropriate temperatures
D) appropriate temperatures
E) nitrogen gas
11) Which of the following is NOT a characteristic of a tropical rainforest?
A) high temperatures
B) very high species diversity
C) arboreal animals
D) vegetation grows in layers
E) fertile soil
12) When succession occurs after a field is abandoned in the southeastern U.S., the rich soil and intense sunlight initially allow fast-growing annual species such as __________ to thrive.
A) ragweed and crabgrass
B) tulip poplars and sweetgum
C) oaks and maples
E) pine trees
13) If a wolf eats a rodent that ate a smaller insect that ate a plant, the wolf would be a(n)
A) primary producer.
B) tertiary consumer.
C) secondary consumer.
D) primary consumer.
14) Eutrophic lakes have
A) very little productivity.
B) clear water.
C) few phytoplankton.
D) high nutrient levels.
E) high oxygen concentrations in deep water.
15) An important density-independent factor limiting population size is __________.
D) food quantity
E) environmental resistance
16) Over the past century, sagebrush has dramatically expanded its range over the Colorado Plateau's grasslands. This has been attributed to the overgrazing of the area's grasses by cattle and sheep. This example indicates that
A) grazing has no effect on the distribution of plants.
B) the relationship between sagebrush and grasses is mutualistic.
C) sagebrush is the dominant competitor over grasses.
D) the range of sagebrush is normally limited by competition with grasses.
E) sagebrush could not exist anywhere in the absence of cattle and sheep.
How would you approach the population problem in cultures where contraception is not accepted? What groups should be given the authority to use your approach?© BrainMass Inc. brainmass.com October 24, 2018, 7:14 pm ad1c9bdddf
Amino acids multiple choice questions
Which statement is incorrect about the classification of amino acids?
a. Alanine and valine are neutral, nonpolar amino acids.
b. Lysine and arginine are basic amino acids.
c. Tryptophan and phenylalanine are aromatic amino acids.
d. Aspartic acid and aspargine are acidic amino acids.
Which of the following amino acids is the least water soluble at pH 7.0?
b. Glutamic acid
Which amino acid would migrate the furthest toward the anode (positive electrode) during paper electrophoresis at pH 7.0?
a. Aspartic acid
Which of the following functional groups, attached to an inert matrix, could function as a cation exchanger?
Which of the following amino acids would make the best buffer at pH 4.5?
d. Aspartic acid
Which fact is incorrect about stereoisomers?
a. A diastereomer is a nonsuperimposable non-mirror image.
b. An enantiomer is a nonsuperimposible mirror image.
c. Diastereomers have different melting points.
d. Diastereomers rotate plane polarized light in equal but opposite direction.
Which statement is incorrect about L-isoleucine?
a. Its enantiomer is named O-isoleucine.
b. It contains a total of two asymmetric or chiral carbons.
c. It can also be named as (28, 38)-isoleucine using the (R,8) system.
d. Its diastereomer would be named O-alloisoleucine.
An isoelectric amino acid was dissolved in water and the resulting pH was approximately 7.6. What amino acid would possess this property?
b. Glutamic acid
What volume of NaOH is required to adjust the solution of monosodium aspartate to pH 9.8?
a. 1 ml
b. 2 ml
c. 3 ml
d. 6 ml or more
What volume of 2 N Hel is required to completely titrate the 4 mmol of monosodium aspartate?
a. 2 ml
d. 6 ml or more
Which statement is correct about the peptide ala-ser?
a. Alanine is at the N-terminal of the peptide.
b. There are a total six atoms that lie in the plane of the peptide bond linking alanine to serine.
c. The alpha-carbon of alanine is sp3 hybridized d All the above are correct statements.
What is the product formed from the acid hydrolysis of a simple amide?
a. Acid & base
b. Aldehyde & alcohol
c. Acid & amine
d. Ester & alcohol
The complete acid hydrolysis of the peptide ala-gln-trp-ser would yield:
a. Ala, gin, trp, ser
b. Ala, glu, ser
c. Ala, glu, trp, ser
d. Ala. ser
Fibrous proteins, such as collagen, have which of the following properties?
a. Highly soluble in water
b. Their hydrophilic residues are directed into the interior of the protein
c. Exhibit enzymatic activity
d. Serve structural roles in the cell
Quaternary structure is associated with:
a. The overall shape of a polypeptide chain
b. The sum of the secondary and tertiary interactions
c. Simple proteins with only one subunit
d. The relative orientation of one polypeptide to another polypeptide in a multi-subunit protein.
The information needed to define the structure of a protein is essentially contained in:
a. Amino acid composition
b. Amino acid sequence
c. Secondary structure
d. Tertiary structure.
Insulin is a polypeptide hormone that contains two short polypeptide chains linked by two interstrand disulfide bonds. The most logical order of events to perform in order to sequence this protein would be:
A: The peptides are reduced with mercaptoethanol.
B: The peptides are sequenced using Edman chemistry .
C: The peptides are separated by chromatography techniques. 0: The peptides are alkylated with iodoacetamide.
a. A, D,C, B b.C,A, 0, B
c. C, B, A, 0
d. A, B, C, 0
Which statement is incorrect about the peptide val-asp-trp-asn-ser?
a. This peptide would show a strong absorption band at 280 nm.
b. Reaction with chymotrypsin would yield two peptides.
c. To synthesize this peptide using the solid phase method of Merrifield, the amino acid directly attached to the resin would be serine.
d. After the second round of Edman chemistry using the reagent PITC, the PTH -amino acid residue released would be PTH-asn.
Which statement is incorrect about the reaction of the peptide ser-Iys-asp-trp-cys-metasn-phe-ala with the following reagents?
a. Reaction with cyanogens bromide would yield two peptides.
b. Reaction with trypsin would result in three peptides. The smallest of three peptides would have the highest pi of the three.
c. Reaciton with chymotrypsin would result in the peptides ser-Iys-asp & try-cys-met-Iysasn-phe-ala .
d. Reaction with chymotrypsin would yield a different set of peptides that overlap those obtained with tryspsin
Determine the amino acid sequence of the following oligopeptide from the experimental data below:
The amino acid composition is found the be ala, Iys, phe, met, cys plus some
2. The peptide has a molecular weight around 700 Da and absorbs at 280 nm.
3. Treatment with carboxypeptidase results in tryptophan and a peptide.
4. CNBr treatment yields a tetrapeptide and a dipeptide.
5. Trypsine digestion produces an amino acid and a pentapeptide with met on the amino end.
6. Chymotrypsin digestion yields a dipeptide and a tetrapeptide.
d. Iys-ala-cys-phe-met -trp