BLG 144 MIDTERM 1 COMPREHENSIVE
EXAMINATION 2026 FULL QUESTIONS AND
CORRECT ANSWERS
◉ homology. Answer: study of likeness
-examining striking similarities among certain organisms that both
inherited the trait from a common ancestor
◉ genetic homology. Answer: occurs in DNA sequences
ex. gene sequences in two different organisms are almost completely
identical
◉ Developmental homology. Answer: recognized in embryos
(development)
-similarity in structures within embryo that either continue to
develop until birth or grow to become another functional trait
◉ structural homology. Answer: similarity in adult morphology or
form
ex. limbs of vertebrates;same structure, different function (grasping
for humans, digging for moles, etc)
, ◉ how do the three levels of homology interact. Answer: genetic
homology causes the developmental homologies observed in
embryos, which lead to structural homologies recognized in adults
◉ darwin's 4 postulates. Answer: 1.individual organisms that make
up a population vary in traits they possess
2. some of the trait differences are heritable;passed on to their
offspring genetically
3. many more offspring are produced than can possibly survive
4. individuals that survive best and produce more offspring is not
random; those with certain heritable traits are more likely to survive
and reproduce
◉ fitness. Answer: ability for an organism to produce surviving
offspring
◉ adaption. Answer: heritable trait that increases the fitness of an
individual in a particular environment relative to individuals lacking
that trait
◉ polygenic. Answer: many genes influencing one trait
◉ true or false:
EXAMINATION 2026 FULL QUESTIONS AND
CORRECT ANSWERS
◉ homology. Answer: study of likeness
-examining striking similarities among certain organisms that both
inherited the trait from a common ancestor
◉ genetic homology. Answer: occurs in DNA sequences
ex. gene sequences in two different organisms are almost completely
identical
◉ Developmental homology. Answer: recognized in embryos
(development)
-similarity in structures within embryo that either continue to
develop until birth or grow to become another functional trait
◉ structural homology. Answer: similarity in adult morphology or
form
ex. limbs of vertebrates;same structure, different function (grasping
for humans, digging for moles, etc)
, ◉ how do the three levels of homology interact. Answer: genetic
homology causes the developmental homologies observed in
embryos, which lead to structural homologies recognized in adults
◉ darwin's 4 postulates. Answer: 1.individual organisms that make
up a population vary in traits they possess
2. some of the trait differences are heritable;passed on to their
offspring genetically
3. many more offspring are produced than can possibly survive
4. individuals that survive best and produce more offspring is not
random; those with certain heritable traits are more likely to survive
and reproduce
◉ fitness. Answer: ability for an organism to produce surviving
offspring
◉ adaption. Answer: heritable trait that increases the fitness of an
individual in a particular environment relative to individuals lacking
that trait
◉ polygenic. Answer: many genes influencing one trait
◉ true or false:
