Download BIOL0601 Practice Examination Key

BIOL0601 Practice Examination
Biology 030 Practice Exam
Page 2 of 20
Multiple Choice
Even though the final will not contain any multiple choice questions, they are included here as a
good way of covering content.
Please circle the letter of the correct answer.
1. In peas, yellow seed colour is dominant over green seed colour. In order to determine the
genotype of a pea with yellow seed it should be crossed with which of the following pea plants?
a) a green seeded plant
b) a hybrid yellow seeded plant
c) a pure yellow seeded plant
d) a hybrid yellow seeded plant or a pure yellow seeded plant
2. If abnormal chromosomal combinations such as XXY, XYY, and normal XY
chromosomal combinations produce males AND abnormal poly X (XXX, XXXX), and
normal XX combinations produce females. The rule for sex phenotype is
a) maleness results from the presence of only one X chromosome.
b) maleness results from the absence of two or more X chromosomes.
c) maleness results from the presence of at least one Y chromosome.
d) femaleness results from the presence of two or more X chromosomes.
e) sex determination is a delicate balance between X and Y chromosomes.
4. Where would we expect the most active cell cycling (growth)?
a) nerve cells
b) skeletal muscle cells
c) stem cells producing epidermis and blood cells
d) all cells cycle at the same general rate
5. The origin of cell organelles in eukaryotes may attributed to
a) invagination of the plasma membrane to form endoplasmic reticulum
b) incorporation of engulfed heterotrophic bacteria to form mitochondria
c) incorporation of engulfed autotrophic cyanobacteria to form chloroplasts
d) attached bacteria to form flagella
e) all of the above are speculated
6. When blood is filtered through the nephrons of the kidney, what happens to albumin (a large
protein), salt ions (Na+, Cl-) and urea?
TRU Open Learning
Biology 030 Practice Exam
a)
b)
c)
d)
e)
Page 3 of 20
All three remain in the blood stream
All three are excreted in urine
All three pass to the glomerular capsule but the salt ions are mostly reabsorbed
Albumin stays in the blood, salt ions and urea pass but are re-absorbed
Albumin stays in the blood, salt ions and urea pass, but only salt ions are re-absorbed.
7. During crossing over in meiosis,
a) chromosomes switch poles.
b)
mitosis becomes meiosis.
c)
chromatin becomes chromosomes.
d)
chromosomes become chromatin.
e) non-sister chromatids from homologous chromosomes exchange
segments of genetic material.
8. Which eukaryotic organelle can best be seen by a light microscope?
a) ribosome
b) nucleus
c) endoplasmic reticulum
d) mitochondria
e) chromatin
9. Which type of muscle is both unstriated and involuntary?
a) skeletal
b) smooth
c) cardiac
d) cartilage
e) bone
10. NADPH and ATP are produced in the
a) citric acid cycle.
b) cyclic electron pathway.
c) Kreb cycle
d) light dependent reactions.
e) light independent reactions.
TRU Open Learning
Biology 030 Practice Exam
Page 4 of 20
11. ___________are the ultimate end products for aerobic cellular respiration.
a) Glucose and carbon dioxide
b) Glucose and water
c) Glucose and oxygen
d) Lactate and carbon dioxide
e) Carbon dioxide and water
14. Which of the following would be an indication of kidney failure?
a)
urea in the urine
b)
salts in the urine
c)
uric acid in the urine
d)
large amount of protein in the urine
e)
dilute urine
15. The best characterization of apoptosis is:
a)
All cell death is bad.
b)
c)
Cell death occurs when a cell lives long enough to eventually be killed by accident.
Killer cells approach a healthy cell and determine when it will die.
d)
Cell death is the consequence of a series of internal cell events.
e)
All cell death is good.
TRU Open Learning
Biology 030 Practice Exam
Page 5 of 20
Diagrams
1. Nephron [10 marks]
Adapted from 02691.Copyright 2002.McGraw-HillCompanies.
Reproduced with permission.
Which of the following molecules will be found in the nephron at each labeled place?
glucose, urea, water, amino acids, creatinine, salts.
A. This is the arteriole leading to the Bowman’s capsule. It will contain all of the listed
substances
B. This is the proximal convoluted tubule. All of the substances appear in the fluid, but
glucose, salts, and amino acids are actively reabsorbed.
C. This is the distal convoluted tubule. Water, urea and creatinine will be present in the fluid.
D. This is the collecting duct. Water, urea and creatinine are still present, as are some salts
that may be excreted here.
E. This is the loop of the nephron. The loop is responsible for adjusting the concentration of
the urine depending on the water balance in the body. Those materials not reabsorbed in
the proximal convoluted tubule are still present.
TRU Open Learning
Biology 030 Practice Exam
Page 6 of 20
2. Digestive System [10 marks]
Label the following diagram of the digestive system, and give a function for each structure.
A.
Gall bladder
stores bile (an emulsifying agent) until
needed
B.
Mouth
Food is mechanically broken into smaller
pieces (chewing) and mixed with saliva.
Digestion of starch starts here.
C.
Stomach
Serves as a storage container for the food.
Food is mixed with acid and enzymes to
form chime. The digestion of proteins starts
in the stomach.
D.
small intestine
Most of digestion and the absorption of
Adapted from 0191bI.Copyright 2002.
McGraw~Hill Companies.
Reproduced with permission
nutrients occurs in the small intestine
E.
rectum
Acts as a storage organ for solid wastes until
elimination (defecation)
TRU Open Learning
Biology 030 Practice Exam
Page 7 of 20
Definitions
Define and note the importance of the following terms:
1. Anaphase: This is the phase of mitosis in which the sister chromatids separate from each
other and migrate toward the poles of the cell.
2. Electron Transport System: Cytochromes are bound to the surface of the cristae of the
mitochondrion. These molecules facilitate the transfer of energy from high energy electrons to
ATP.
3. Tissue: A tissue is group of similar cells that perform a common function.
4. Urea: Derived from the breakdown of amino acids, it is the primary nitrogenous waste in
humans.
5. Nondisjunction: The failure of homologous chromosomes or sister chromosomes to
separate during meiosis 1 and meiosis 2
6. Hormone: A chemical messenger carried by the blood that has an effect on a distant
organ.
7. Neuron: The functional subunit of the nervous system responsible for the transmission of
impulses. (it typically has 3 parts: dendrites, cell body and axon)
8. ADH: antidiuretic hormone secreted by the posterior pituitary that increases the
permeability of the collecting ducts of the kidney, thus producing a more concentrated urine.
9. Red bone marrow: a tissue in the centre of large (spongy) bones responsible for the
formation of blood cells.
10. Villi: small finger like projections in the small intestine which increase the surface area and
absorb nutrients from the small intestine.
TRU Open Learning
Biology 030 Practice Exam
Page 8 of 20
Distinctions
Provide one similarity and one difference between:
1. Theory and hypothesis: They both concern scientific ideas, but a hypothesis is an
educated guess subject to testing by experimentation and a theory is a generally accepted
statement that has proved to be true over time.
2. Mitosis and meiosis: Both involve the duplication of DNA and the movement of
chromosomes, but mitosis results in 2 identical cells with a chromosome number of 2N and
meiosis results in the formation of gametes with a chromsomes number of N.
3. Chromosomes and Chromatin: Both involve DNA, but chromatin is the name of the
DNA-protein complex in the nucleus and chromosome is the name applied to the DNA when it
has condensed enough to be visible as discrete strands under the light microscope.
4. Gall bladder and urinary bladder: Both are storage containers, but the gall bladder stores
bile whereas the urinary bladder store urine.
5. Stomach and pancreas: Both have an exocrine and an endocrine function, but the
stomach serves as a storage container and the pancreas doesn’t.
TRU Open Learning
Biology 030 Practice Exam
Page 9 of 20
Fill in the Blanks
1. Use the following list of words to fill in the blanks. Not all words will be used and
some might be used more than once.
antagonistic, ATP, complementary, diffusion, electrons, energy, enzyme, fermentation,
gamete, neutrons, osmotic, photosynthesis, protein, red blood cell, son, water, ADP,
respiration
a) active cells must continually produce ATP to serve its energy needs.
b) The only haploid cells in the human life cycle are the sperm or egg.
c) Traits associated with X-linked genes are generally transmitted from a grandfather via
a normal mother to her son.
.
d) NADH and FADH2 bring high energy electrons and hydrogen ions to the electron
transport system.
e) Base pairing in DNA and RNA always pairs a purine with a pyrimidine.
f)
Osmotic pressure causes water to move across a membrane.
g Less energy is needed to bring about a chemical reaction when an enzyme is
present.
TRU Open Learning
Biology 030 Practice Exam
Page 10 of 20
Matching/Compar
ison
Match the term with the description by placing the appropriate letter in the left
hand column.
term
J
F
description
A Drainage of fluid from
tissues
Cardiovascular system
B Removal of nitrogenous
waste
Digestive system
D
Endocrine system
C Gas exchange with outside
Environment
B
Excretory system
D Hormones
H
Integumentary system
E Learning
A
Lymphatic system
F Peristalsis
I
Musculoskeletal system
G Production of gametes
E
Nervous system
H Hair follicles
G
Reproductive system
I
Red blood cell production
C
Respiratory system
J
Transport of oxygen to cells
2. Comparison
Compare the production of gametes with that of somatics cells by answering true or false in
the following table
Have a chromosome number of N
Are produced by meiosis
DNA is replicated during the formation
RNA plays a central role in this process
Resulting cells are identical to the original
gametes
T
T
T
F
F
TRU Open Learning
somatic cells
F
F
T
F
T
Biology 030 Practice Exam
Page 11 of 20
G. Revisions
The following statements are false. Rewrite them to give a true statement.
1. The process of secretion can occur by exocytosis.
2. Nondisjunction of chromosomes occurs in meiosis when homologous chromosomes fail
to separate.
3. A substrate can participate in only several types of reaction.
4. Oxygenated and deoxygenated blood kept separate in the heart.
5. ATP is produced during the process of internal or cellular respiration.
TRU Open Learning
Biology 030 Practice Exam
Page 12 of 20
H. Short Answer
1. Explain what makes a molecule hydrophilic, and give an example of a macromolecule that is
hydrophilic.
A hydrophilic molecule is “water loving” - It will dissolve in water. This is because one
end has a charge or positive charge that interacts (forms hydrogen bonds) with water.
An example of this is the glucose molecule.
2. How is a nerve impulse transmitted from one neuron to another?
The gap between the dendrites of one neuron and the axon of another is called the
synapse. The impulse is transmitted across the synapse by a neurotransmitter.
3. Give 5 differences between the large and small intestines
1 – the small intestine is much longer than the large intestine
2 – the small intestine is smaller in diameter than the large intestine
3 – digestion happens only in the small intestine
4 – nutrients are absorbed in the small intestine and water in the large
5 – the large intestine maintains a large and important bacterial flora
4. Explain how enzymes affect the activation energy.
When the active zone of an enzyme interacts with the substrate, the activation energy
of the chemical reaction is decreased. This allows the reaction to occur more easily at
a lower temperature.
5. What is the function of the myelin sheath?
The myelin sheath increases the rate of transmission of the nerve impulse. The nerve
impulse is transmitted along a neuron by a snow balling process. The action potential
at one spot causes an action potential at an immediately adjacent spot. The myelin
sheath has nodes that are fairly far apart, and the nerve impulse jumps from node to
node, increasing the transmission rate of the neuron.
TRU Open Learning
Biology 030 Practice Exam
Page 13 of 20
I. Genetics Problems
1. In humans, albinism results in no pigment formed in the skin. Albinism is a homozygous
recessive trait (aa) and pigmented individuals may be either (AA) homozygous or
heterozygous (Aa).
a) Show the possible gametes’ genotypes and their proportions if produced by the
following individuals:
Individual’s Genotype
Gametes Produced and %
A and a - 50%/50%
heterozygous
a 100%
homozygous recessive
A 100 %
homozygous dominant
b) If a homozygous dominant man and a homozygous recessive woman have a child, what
is the probability that a child will be an albino?
Zero percent. All children will be heterozygous and show the dominant (normal)
phenotype.
c) If a heterozygous man and a heterozygous woman have a child, what is the probability
that the child will be an albino?
There is a 25% chance (1 in 4) that th4\e child will be albino.
2
Hair length and hair colour are controlled by independently assorting genes. A dominant
allele determines short hair (S) and a recessive allele determines long hair (s). For hair
color, yellow is determined by a dominant allele (Y) and white by a recessive allele (y).
You cross a male and a female who are both heterozygous for both genes.
a)
Give the genotypes and phenotypes of each parent.
They are both SsYy (short and yellow hair)
b)
Show the expected phenotypic ratios among their offspring.
The ratio will be 9/16 short-yellow, 3/16 short-white, 3/16 long-yellow, and 1/16
long-white
TRU Open Learning
Biology 030 Practice Exam Answer Key
Page 14 of 8
Long Answer
Your answer should be two to three paragraphs long.
1. Describe the structure and function of lipids.
a. lipids are also called fats
b. fatty acids are long chain molecules; the carbon end is hydrophobic and the
acid (carboxyl) end is hydrophilic
c. Fatty acids and glycerol produce the triglyceride
d. A modification if the triglyceride called a phospholipid forms the main
component of the plasma membrane; it has a hydrophobic end and a
hydrophilic end
e. The properties of the plasma membrane derive from the
hydrophobic/hydrophilic properties of the phospholipids
f.
Fats in the body are s storage form of energy, and provide insulation.
2. Explain the differences between steroid and peptide hormones, and describe how they act
upon their target cells.
a. Steroid hormones have the core of four fused rings which characterizes a
steroid. Peptide hormones have a core of a peptide or modified amino acid,
and may have also have molecules such as carbohydrates attached. They
differ also in how they act upon their target cells. A steroid, being a lipid,
can diffuse across the plasma membrane. A peptide hormone does not
usually cross the membrane.
A peptide hormone binds to a receptor protein on the cell surface, which
stimulates a cascade of enzymatic reactions inside the cell. Each step inthe
cascade can amplify a signal, so that very little hormone is needed to
stimulate a major response.
A steroid hormone passes into the cell nucleus, where it binds to a receptor
protein, which then binds to a specific DNA sequence and activates a
particular gene. Since an activated gene can produce multiple copies of an
mRNA which can then each be used to produce multiple copies of a protein,
very little hormone is needed to produce a large response.
3. You are a scientist on a team designing a planetary rover whose purpose is to determine if
life is present on a planet. If the rover finds an object, how will you tell if it is alive or not?
Assuming that all the technical difficulties are solved, the only criteria we have are
TRU Open Learning
Biology 030 Practice Exam Answer Key
Page 15 of 8
the six characteristics of life that we have identified in this course. We have studied
six characteristics of life on Earth. There are many things on earth that are
organized, like crystals, but they are not alive. Things reproduce, making exact
copies of themselves, but they are not alive. There are things that take materials
and energy from their environment, but are not alive. In fact there are many
systems which show several of these characteristics, but are not considered alive.
It is likely that we will have to find something that shows at least 5, if not all six of
the characteristics of life.
[The best marks would go to those students who have made an honest and good
effort to deal with the question, and have shown a scientific approach to the topic.]
TRU Open Learning