Download BIO 1109 – Principles of Biology Midterm examination 2

BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
BIO 1109 – Principles of Biology
Midterm examination 2
Worth either 30% or 40% of your final grade
Wednesday, November 10, 2004
a) Place your name and student number in the space provided below. Be sure that your name is
on the top of each page because the exam may be separated to facilitate marking
b) Check to be sure that your exam is complete with a total of 13 pages including this one
c) Answer all questions in the space provided on the exam. Do not transfer answers to the back
of the page
d) This is not an open book examination.
Name: ...........................................................................................................
Student No: ...................................................................................................
Page 1 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
15 pts Part 1. Briefly explain what each of the following biological terms means. Where possible
include an example to which the term applies.
Transition reaction (in metabolism)
{links glycolysis and TCA/Citric acid cycle}{Pyruvate(3C) loses a carbon}{produces
acetylCoA} Point each
Nucleosome
{piece of DNA}{wound around a core of histone proteins){string of beads}{may be wound on
them selves to form coiled nucelosomes}{2 points for the first two that must be present} a
single pint for additional to a maximum of three
Endosymbiont theory
{origins of eukaryote cells}{engulphs/phygocytosis of a prokaryote}{Cell with a
nucleus/endomembrane system surrounding nucleus}{includes mitochondria in all
eukaryotes/chloroplasts in plants} {11, first two must be present} and other 1 for a maximum
of three points
Central dogma of Biology
{DNA produces DNA}{RNA comes from DNA, occasionally reversed with retrovirus } and
{Proteins from RNA} This can be presented as a diagram, 1 point each, in the second
retrovirus statement is not required but may be provided by some students.
Polyploid
{chromosome number} {greater than the usual diploid number} {found in plants/lethal in
animals} Point each either, or both parts of the third may be used as the example.
Page 2 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
25 pts Part 2 Answer each of the following multiple choice questions by placing and X in the
space to the left of the correct choice. There is only one correct answer for each question and
questions have either 4, 5 or 6 answers to choose from. Be sure your X doesn’t cross over
two answers – if it does the question will be scored as 0.
2.1 Which best describes the second law of thermodynamics?
____________A. Energy is not created nor destroyed, but it can change into matter.
____________B. Energy is not created nor destroyed, but it can change from one energy form
to another.
____________C. Energy can be created from matter or used to produce matter.
____________D.
Some useful energy is lost as heat whenever an energy transfer occurs.
X
____________E. Energy transfers are always 100% efficient in changing energy from one
useful form to another.
2.2 Which of these processes occurs in the cytosol?
____________A. the Krebs cycle
____________B.
glycolysis
X
____________C. the electron transport system
____________D. the transition reaction
2.3 What establishes the electrochemical gradient across a membrane to provide energy for ATP
production?
____________A. The chloroplast’s electron transport system provides the ions.
____________B. Hydrogen ions naturally collect on the outside of the organelle membrane.
X
____________C.
Hydrogen ions are pumped across the membrane by carrier proteins.
____________D. All of the above establish the electrochemical gradient.
2.4 Which pairing of occurrence and date is NOT correct?
____________A. origin of multicellular organisms—550 million years ago
____________B.
origin of life—4.8 billion years ago
X
____________C. origin of eukaryotic cells—1.5 billion years ago
____________D. All the above are incorrect.
2.5 What are the products of photosynthesis?
____________A. water and carbon dioxide
____________B. water and oxygen
____________C.
oxygen and carbohydrate
X
____________D. carbohydrate and water
Page 3 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
2.6 The first reaction in the Krebs cycle is binding
____________A. carbon dioxide to a four-carbon (C4) molecule.
____________B. carbon dioxide to a five-carbon (C5) molecule.
____________C.
acetyl-CoA to a C4 molecule.
X
____________D. acetyl-CoA to a C5 molecule.
2.7 Bacterial cells pick up free pieces of DNA from the medium–pieces that were secreted by live
bacteria or released from dead bacteria–in a process called
____________A. transformation.
____________B.
transduction.
X
____________C. conjugation.
____________D. infection.
____________E. replication.
2.8 The first event in the Calvin cycle is the attachment of carbon dioxide to the five-carbon
RuBP molecule, which
____________A. forms a six-carbon molecule that immediately breaks down into two
three-carbon PGA molecules.
____________B. is a reaction assisted by large quantities of RuBP carboxylase enzyme.
____________C. decreases cell carbon dioxide levels, which increases the diffusion gradient.
____________D. immediately becomes a six-carbon sugar that is the base for starch, sucrose,
cellulose, etc.
X
____________E.
Answers A, B, and C are correct.
2.9 Prokaryotae are now divided into the
____________A. archaea and cyanobacteria.
____________B. bacteria and cyanobacteria.
____________C. photosynthetic bacteria and chemosynthetic bacteria.
____________D. archaea and bacteria.
____________E. autotrophs and heterotrophs.
2.10 Which statement is NOT true about genetic control in prokaryotes?
____________A. RNA polymerase must bind to a promoter on the DNA to begin RNA
synthesis.
____________B.
Most gene expression is regulated at the level of translation.
X
____________C. An active repressor protein keeps RNA polymerase from binding to DNA.
____________D. Structural genes produce enzymes that act in a metabolic pathway.
Page 4 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
2.11 The first level of primary control in eukaryotic gene activity is _______ control.
____________A. feedback
____________B. translational
____________C
.transcriptional
X
____________D. posttranscriptional
____________E. posttranslational
2.12 The Calvin cycle requires all of the following except _____________ to occur.
____________A. ATP,NADPH
____________B. carbon dioxide
X
____________C.
light
____________D. ribulose bis-phosphate
2.13 Skin color in humans, caused by several genes at several loci, is an example of
____________A. multiple alleles at one locus.
____________B. incomplete dominance.
____________C. epistasis.
____________D. pleiotropy.
____________E.
polygenic inheritance.
X
2.14 If the parents are AO and BO genotypes for the ABO blood group, their children could
include which ofthe following genotypes?
____________A. AO and BO only
____________B. AO, BO, and AB only
____________C. AA, BB, and AB only
____________D. AO, BO, and OO only
____________E.
AO, BO, AB, and OO only
X
2.15 A line of evidence NOT considered by Darwin in his development of the theory of natural
selection is
____________A. comparative anatomy.
____________B. biogeography.
____________C. the fossil record.
____________D. comparative embryology.
X
____________E.c
omparative biochemistry.
Page 5 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
2.16 All the members of a single species that occupy a particular area at the same time are known
as a
____________A. subspecies.
____________B. gene pool.
____________C.
population.
X
____________D. group.
____________E. sub-population.
2.17 What is the term used to describe the accumulation of small changes in the gene pool of a
species over time?
____________A. genetic drift
____________B. founder effect
____________C.
microevolution
X
____________D. directional selection
2.18 ATP
____________A. supplies energy needed to synthesize macromolecules within the cell.
____________B. supplies energy required to pump substances across the plasma membranes.
____________C. is the energy source for muscles to contract.
____________D.
all of the previous.
X
2.19 If the Hardy-Weinberg equilibrium is met, what is the net effect?
____________A. evolution leading to a population better adapted to an unchanging
environment
____________B. evolution leading to a population better adapted to a changing environment
____________C. very slow and continuous evolution with no increased adaptation
X
____________D.
no evolution because the alleles in the population remain the same
2.20 Which level of primary control in eukaryotic gene activity involves processing early RNA
transcripts to mRNA and control of the rate at which mRNA leaves the nucleus?
____________A. feedback control
____________B. translational control
____________C. transcriptional control
____________D.
posttranscriptional control
X
____________E. posttranslational control
Page 6 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
2.21 The Greek root words for “arrange” and “law” underlie the biological term
____________A. binomial.
____________B.
taxonomy.
X
____________C. systematics.
____________D. nomenclature.
____________E. systema naturae.
2.22 Of these categories which is highest in classification hierarchy, that is, it includes the rest of
the categories given?
____________A. order
____________B. genus
____________C. class
____________D. family
____________E.
phylum
X
2.23 Single celled eukaryotic cells belong to which of the following kingdoms?
____________A. Monera
____________B.
Protista
X
____________C. Fungi
____________D. Animalia
____________E. Plantae
2.24 The appearance of photosynthetic cyanobacteria and aerobic bacteria
____________A. led to the development of an oxidizing atmosphere on Earth.
____________B. led to the formation of the ozone shield.
____________C. The amount of UV light reaching the Earth was reduced and chemical
evolution slowed.
X
____________D.
all of the previous.
2.25 What evidence would be studied by a biogeographer?
____________A. continental drift or the movement of tectonic plates over time
____________B. amount of genetic similarity among current populations
____________C. ocean currents and wind patterns
____________D. ranges of animals and ability to migrate
____________E.
All of the above are correct.
X
Page 7 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
20 pts Part 3: Indicate whether the following statements are true of false by placing a T (true) or
F (false) in the space provided at the beginning of the statement.
3.1 _____
T An example of an inducible operon is the lac operon.
3.2 _____
T As energy is converted into heat and work in a cell, the energy will either leave the cell
or be stored in various chemical bonds.
T Fossil fuels are full of energy stored from photosynthesis millions of years ago.
3.3 _____
3.4 _____
F Light-dependent reactions occur after light-independent reactions in the process of
photosynthesis.
F The most efficient pathway for ATP production in animal cells is by glycolysis.
3.5 _____
3.6 _____
F The Hardy-Weinberg equilibrium is usually met in most populations in changing
environments.
3.7 _____
T ATP is produced and used continuously in all active cells.
3.8 _____
F Glycolysis is linked to the Krebs cycle when oxygen is not available.
3.9 _____
F Probably the most important means of gaining new genetic material for prokaryotic
evolution is sexual recombination.
3.10 ____
F Mendel developed a blended theory of inheritance.
3.11 ____
F If an individual is heterozygous for a particular trait, the gametes that individual
produces will contain 3/4 dominant and 1/4 recessive alleles.
3.12 ____
F Chemiosmotic ATP synthesis occurs in the cytosol of the cell.
3.13 ____
F Linnaeus, who developed the binomial system of naming species, was a strong
supporter of the theory of evolution.
3.14 ____
T One of the unifying theories of biology is the theory of evolution.
3.15 ____
F An allele becomes the most common allele in a population by becoming the dominant
allele.
3.16 ____
F Mendel's work was widely accepted and praised when he reported his results.
3.17 ____
F The Great Salt Lake would be an excellent location to find methanogens.
3.18 ____
T The cell wall of the bacteria contains a molecule found nowhere else called
peptidoglycan.
3.19 ____
T Active cells must continually produce ATP.
3.20 ____
T Evolution can be described as the change of species over time.
Page 8 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
30 pts Part 4: Use one or two words to answer the question, or complete the sentence. Place
your answer in the space provided or at the end of the question if the line is missing.
4.1 Solar energy is stored in ATP and this compound during photosynthesis ___NADPH_______
4.2 This metabolic process produces both NADH and FADH2. __Krebs/citric acid___________
4.3 The traits Mendel studies in garden peas showed this kind of dominace. ___Complete______
4.4 These vents in the deepest parts of the oceans may also be the original site of the formation of
the first organic chemicals. _____Hydrothermal____________
4.5 Shape of the bacterial genome. ___Circular_______________
4.6 These breakdown carbohydrates during digestion. _Charbohydrases_______________
4.7 Life's process are regulated and kept in balance, a biological process referred to
as this. ___homeostasis___________
4.8 Simple bacterial cell duplication.___Binary fission_______________
4.9 The stacked disks in a chloroplasts.___Thylakoids______________
4.10 This organelle captures the sun's energy. __Chloroplast______________
4.11 If the sugars and amino acids that result from digestion are formed inside the cell it's this type
of digestion. ___Intracellular_______________
4.12 These bacteria produced the natural gas that we currently burn as fuel. ____Methanogens___
4.13 Taxon above a family but below a class. __Order______________
4.14 Unlike organisms in the other two domains, bacteria don't have these interrupting the gene
sequence. ___Introns_________________
4.15 Preventing the production of the primary RNA transcript is an example of this type of
control. ____Transcriptional_________________
4.16 This part of the range of variation is selected for in disruptive selection. __Middle_________
4.17 Electron transport system is found on this part of mitochondria. _Cristae/Inner
membrane___
4.18 Photosynthesis shuts down in the presence of oxygen, especially when the stomata are closed.
When that happens this occurs. __Photorespiration________________
4.19 The energy of motion. ___Kinetic_________________
4.20 In English grammar the species epithet or part of the name would be this. __Adjective______
4.21 Every animal in a taxon shares this type of ancestor. ___Common________________
4.22 Number of carbons in the molecule at the start of glycolysis. ____Six_____________
4.23 The final step in digestion is to break down the biopolymers of protein, carbohydrate, and
lipids into these so that they can be used by the cell. __Monomers______________
Page 9 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
4.24 Will CAP be bound or unbound to the lac operon when lactose is low and glucose is
elevated? ____Unbound________________
4.25 Swamp gas, natural gas, and bovine flatulence all have this archaean produced gas in
common. __Methane_________________
4.26 Bacterial locomotary structure. ___flagellum_______________
4.27 Conditions of low pH. ___acidic________________
4.28 Transcription occurs only in this type of chromatin. __Euchromatin/Unwound___________
4.29 The evolutionary history of a group of organisms is expressed as its ___Phylogeny________
4.30 Jumping genes. __Transposons____________
15 pts Part 5: Answer 3 of the following 6 questions in the space provided, each is worth 5
points.
5.1 Various conditions can alter the activity of an enzyme, briefly what are these and what
results?
OR
Why are plants green and how is this related to photosynthesis
{substrate concentration – as it rises so does enzyme activity}
{enzyme concentration – the more enzyme the more activity}
{Temperature – rises to a point when activity crashes because of protein denaturation/damage
from heat}
{Inhibitors – of either the active site or allosteric/other site on the surface, can shut the enzyme
down}
{pH – enzymes have optimal/favoured pH for activity of of this there is less activity}
{co factors – some enzymes need minerals or other inorganic cofactors}
{2},{2},{1} Only need to give three with an explanation point for the condition and pint for the
result. Score third as a single point for a maximum of five
OR
{Reflect back the green light/absord the rest of the spectrum} {Chloryphyll}{a and
b}{Carotenoids} are the absorbing pigments {Blue/red/violet parts of the spectrum used}
point each to a total of five
Page 10 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
5.2 Describe the planet earth during the Archeon eon be sure to include what identifies the start
and the end of the eon.
OR
What are the RNA-first and Protein-first theories trying to explain?
{Starts with first living things – archean bacteria/prokaryotes}{ends with the oxygen atmosphere
still only bacteria}{Age of bacteria/prokaryotes}{no oxygen in air/reducing environment}{archea
or extreme bacteria} {genome swapping between bacteria} {from 3.8 - 2.5 billion years ago}
First three must be there for three points and of the others to a maximum of 5 points
OR
{How were the first biopolymers formed*}
RNA first says that {RNA strands were first biopolymers* and proteins came latter} {had
catalytic abilities} {supported by recent findings of rNA catalysis} {matches direction of central
dogma}
Protein first says that {proteins were first biopolymers and RNAor DNA can after*} {supported
by proteins being the usual catalysts} 3* points must be there for a point each, a supporting piece
of evidence one for each only to give the full five points.
5.3 What is an operon what are its parts and what does each do?
OR
What does the regulator gene of an operon produce and how does its product regulate gene
activity?
{Promotor} – {Binds RNA polymerase}
{Operator} – {Site where the repressor can bind}
{Structural genes – the genes coding to be translated}
Note: The regulator gene is outside the operon
OR
{Located outside the operon}{produces a protein} {that binds to Operator} {If bound prevents
translation} {acts as an on/off switch} {May be inducible / repressable} First four must be there
and a point each, either of the last two to give a maximum of five
Page 11 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
5.4 Explain the following: a monohybrid cross and a testcross.
OR
Mendel’s findings resulted in two laws of genetics, what are they and what does each explain?
Monohydrid cross {homozygous recessive tt x homozygous dominant TT} results {heterozygote
Tt} young/F1
TestCross { any individual} x {homozygous recessive tt}
3 points for monohybrid {2 for use of terms and letters/ one for of either} {1} and point each as
indicated for testcross
{Law of segregation}: {two alleles/foactors per trait} {allelels separate during gamete formation/
gamete ges only one of each}{recombine and return to two on fertilization
{Independent assortment} {alleles/trait sort mix in new organism independent of each other}{can
mix and match in any number of ways}
5.5 Trace carbons through one of the following: Glycolysis, Kreb’s cycle, or the Calvin cycle.
Kreb’s Cycle:{2 carbon acetyl CoA}{combines with 4C oxaloacetate}{to produce 6C citric
acid} {2C removed as carbon dioxide}{rebuild the oxaloacetate from the remaining 4C after the
carbon dioxides are removed} 1:1:1:1:1
Glycolysis {6C glucose start}{activated into 6C fructose diphosphate}{split in two to make 2
PGAL phosphoglyceraldehyde glyceraldehydes 3 phosphate}{transformed into 3C pyruvate}
1:1;2;1;1
Calvin cycle: {5C compound}{combines 1C in Carbon dioxide} {unstable and breaks into 3C phosphoglycerate}
{6x3C with one to building}{remaining 5X3C changes to 3X 5C} 1:1:1:1:1
Page 12 of 13
BIO 1109 Midterm Exam –November 10, 2004
Name: _____________________________ Student Number:_____________________________
5.6 Changes in chromosomal structure can be a source of variation, what kinds of changes can
occur? Explain each.
OR
What is the difference between homologous and analogous structures, which are best for
determining how groups or organisms are related to each other and why?
Inversion: a,b,c,d,e,f,g, becomes a,b,d,c,e,f,g
Translocation: two chromosomes swap pieces
Deletion a,b,c,d,e,f,g becomes b,c,d,e,f,g,
Duplication: a,b,c,d,e,f,g, becomes a,b,c,d,e,f,d,e,f,g
{2 for the first properly described and a point each for the rest to a maximum of five
Homologous: {Different function but have the same origin/embryology/developmental} {ex:
wings of birds, bats etc}
Anologous: {Same function but have different origin/embryology/developmental} ex: wing of an
insect and a vertebrate wing}
{Homologies are best for figuring out who is related} point eah to a maximum of five
Page 13 of 13