Biology & Life Sciences
3 MAXE · 171 OIB
◆ ◆
Department of Genetics & Evolutionary Biology
BIOLOGY
EXPLORING THE SCIENCE OF LIFE
BIO 171 Exam 3 — Genetics, Evolution & Ecology
CO M P R E H E N S I V E E X A M I N AT I O N : M E N D E L I A N G E N E T I CS · L I N KAG E · M E I O S I S ·
M U TAT I O N S · B I O D I V E RS I TY · M I C R O B I O M E
INSTITUTION [UNCONFIRMED] — BIO 171 COURSE CODE BIO 171
General Biology
PROGRAM [INFERRED] — Associate / ACADEMIC YEAR
Bachelor of Science
EXAM TITLE BIO 171 Exam 3 — Genetics, TOTAL QUESTIONS 100 Questions
Evolution & Ecology
COURSE TITLE General Biology II — Genetics & FORMAT Multiple Choice — Select the
Ecology Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question based on BIO 171 Exam 3 content.
▸ Questions cover Mendelian genetics, linkage, meiosis, mutations, biodiversity, microbiome, and
conservation ecology.
▸ Correct answers and detailed rationales provided for comprehensive exam preparation.
, SECTION I — BIO 171 EXAM 3: GENETICS, EVOLUTION &
Questions 1 – 100
ECOLOGY
1. What is species extinction?
A. A local population disappears but the species survives elsewhere
B. A species is completely gone — no living members remain anywhere on Earth
C. A species becomes endangered but can still recover
D. A species moves to a new habitat and abandons its original range
CORRECT ANSWER B — A species is completely gone — no living members remain anywhere on
Earth
RATIONALE Species extinction is the permanent loss of all individuals of a species — the
species ceases to exist. This is distinct from population extirpation (local
extinction, option A), where a species disappears from a particular area but
survives elsewhere. Human activities have dramatically accelerated extinction
rates: 322 vertebrate species have gone extinct since 1500. Scientists debate
whether we are currently experiencing a sixth mass extinction event. Extinction is
irreversible — once a species is gone, its unique evolutionary history, ecological
functions, and potential benefits (medicines, ecosystem services) are lost forever.
The current extinction rate is estimated to be 100–1,000 times higher than the
natural background rate.
,2. What is mitosis and what is its purpose?
A. Cell division that produces four genetically different haploid gametes
B. In eukaryotes, replicates chromosomes, separates copies into different cells, and
produces 2 genetically identical daughter cells — used for growth, repair, and asexual
reproduction
C. The process by which bacteria divide through binary fission
D. The fusion of two gametes to form a diploid zygote
CORRECT ANSWER B — In eukaryotes, replicates chromosomes, separates copies into different
cells, and produces 2 genetically identical daughter cells — used for
growth, repair, and asexual reproduction
RATIONALE Mitosis is the process of nuclear division in eukaryotic cells that produces two
daughter cells genetically identical to the parent cell. Key steps: (1) Chromosomes
replicate during S phase; (2) During mitosis (prophase, metaphase, anaphase,
telophase), the replicated chromosomes are separated; (3) Cytokinesis divides the
cytoplasm. Mitosis serves three main purposes: growth and development from a
fertilized egg into an adult organism, repair and regeneration of tissues, and
asexual reproduction in some species. Mitosis occurs in somatic (body) cells. It
differs from meiosis (option A), which produces four genetically different haploid
gametes through two rounds of division. All multicellular eukaryotes depend on
mitosis for development and maintenance.
, 3. Why did Thomas Hunt Morgan use Drosophila melanogaster to study inheritance?
A. They have complex behaviors that are easy to observe
B. They are small, easy to raise and cross, have genetic variation in phenotypes, and have a
short 2-week generation time — allowing study of P, F1, and F2 generations in only 6
weeks
C. They have the largest genome of any model organism
D. They reproduce exclusively through asexual reproduction
CORRECT ANSWER B — They are small, easy to raise and cross, have genetic variation in
phenotypes, and have a short 2-week generation time — allowing study of
P, F1, and F2 generations in only 6 weeks
RATIONALE Drosophila melanogaster (fruit fly) was the first genetic model system and
remains at the forefront of genetics today. Morgan chose them because: (1) Small
size — millions can be kept in a laboratory; (2) Easy to raise and cross — just need
males, females, and food; (3) Genetic variation in visible phenotypes (eye color,
wing shape); (4) Short generation time of ~2 weeks — he could study the passage
of traits from P → F1 → F2 in only 6 weeks. Morgan discovered the first genetic
mutant — a white-eyed fly instead of normal red eyes — and began the tradition
of naming genes after mutant phenotypes. His work provided the first strong
evidence that genes are located on chromosomes (chromosomal theory of
inheritance), earning him the Nobel Prize.
3 MAXE · 171 OIB
◆ ◆
Department of Genetics & Evolutionary Biology
BIOLOGY
EXPLORING THE SCIENCE OF LIFE
BIO 171 Exam 3 — Genetics, Evolution & Ecology
CO M P R E H E N S I V E E X A M I N AT I O N : M E N D E L I A N G E N E T I CS · L I N KAG E · M E I O S I S ·
M U TAT I O N S · B I O D I V E RS I TY · M I C R O B I O M E
INSTITUTION [UNCONFIRMED] — BIO 171 COURSE CODE BIO 171
General Biology
PROGRAM [INFERRED] — Associate / ACADEMIC YEAR
Bachelor of Science
EXAM TITLE BIO 171 Exam 3 — Genetics, TOTAL QUESTIONS 100 Questions
Evolution & Ecology
COURSE TITLE General Biology II — Genetics & FORMAT Multiple Choice — Select the
Ecology Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question based on BIO 171 Exam 3 content.
▸ Questions cover Mendelian genetics, linkage, meiosis, mutations, biodiversity, microbiome, and
conservation ecology.
▸ Correct answers and detailed rationales provided for comprehensive exam preparation.
, SECTION I — BIO 171 EXAM 3: GENETICS, EVOLUTION &
Questions 1 – 100
ECOLOGY
1. What is species extinction?
A. A local population disappears but the species survives elsewhere
B. A species is completely gone — no living members remain anywhere on Earth
C. A species becomes endangered but can still recover
D. A species moves to a new habitat and abandons its original range
CORRECT ANSWER B — A species is completely gone — no living members remain anywhere on
Earth
RATIONALE Species extinction is the permanent loss of all individuals of a species — the
species ceases to exist. This is distinct from population extirpation (local
extinction, option A), where a species disappears from a particular area but
survives elsewhere. Human activities have dramatically accelerated extinction
rates: 322 vertebrate species have gone extinct since 1500. Scientists debate
whether we are currently experiencing a sixth mass extinction event. Extinction is
irreversible — once a species is gone, its unique evolutionary history, ecological
functions, and potential benefits (medicines, ecosystem services) are lost forever.
The current extinction rate is estimated to be 100–1,000 times higher than the
natural background rate.
,2. What is mitosis and what is its purpose?
A. Cell division that produces four genetically different haploid gametes
B. In eukaryotes, replicates chromosomes, separates copies into different cells, and
produces 2 genetically identical daughter cells — used for growth, repair, and asexual
reproduction
C. The process by which bacteria divide through binary fission
D. The fusion of two gametes to form a diploid zygote
CORRECT ANSWER B — In eukaryotes, replicates chromosomes, separates copies into different
cells, and produces 2 genetically identical daughter cells — used for
growth, repair, and asexual reproduction
RATIONALE Mitosis is the process of nuclear division in eukaryotic cells that produces two
daughter cells genetically identical to the parent cell. Key steps: (1) Chromosomes
replicate during S phase; (2) During mitosis (prophase, metaphase, anaphase,
telophase), the replicated chromosomes are separated; (3) Cytokinesis divides the
cytoplasm. Mitosis serves three main purposes: growth and development from a
fertilized egg into an adult organism, repair and regeneration of tissues, and
asexual reproduction in some species. Mitosis occurs in somatic (body) cells. It
differs from meiosis (option A), which produces four genetically different haploid
gametes through two rounds of division. All multicellular eukaryotes depend on
mitosis for development and maintenance.
, 3. Why did Thomas Hunt Morgan use Drosophila melanogaster to study inheritance?
A. They have complex behaviors that are easy to observe
B. They are small, easy to raise and cross, have genetic variation in phenotypes, and have a
short 2-week generation time — allowing study of P, F1, and F2 generations in only 6
weeks
C. They have the largest genome of any model organism
D. They reproduce exclusively through asexual reproduction
CORRECT ANSWER B — They are small, easy to raise and cross, have genetic variation in
phenotypes, and have a short 2-week generation time — allowing study of
P, F1, and F2 generations in only 6 weeks
RATIONALE Drosophila melanogaster (fruit fly) was the first genetic model system and
remains at the forefront of genetics today. Morgan chose them because: (1) Small
size — millions can be kept in a laboratory; (2) Easy to raise and cross — just need
males, females, and food; (3) Genetic variation in visible phenotypes (eye color,
wing shape); (4) Short generation time of ~2 weeks — he could study the passage
of traits from P → F1 → F2 in only 6 weeks. Morgan discovered the first genetic
mutant — a white-eyed fly instead of normal red eyes — and began the tradition
of naming genes after mutant phenotypes. His work provided the first strong
evidence that genes are located on chromosomes (chromosomal theory of
inheritance), earning him the Nobel Prize.
