BIO 148 - Midterm 2 Exam Questions with Correct Answers Latest Update 2025/2026
Which of the below is a key event in an organism's life history?
Survival to adulthood
Reproduction
Metamorphosis
All of the options are correct - Answers All of the options are correct
What the key advantage of sexual reproduction compared to asexual reproduction?
Sexual reproduction creates genetic diversity whereas asexual reproduction creates genetic
clones
Unequal contribution to gametes (isogamy) in sexual reproduction means that reproduction is
less costly for one sex in a population, which can stop the population from going extinct
All else equal, sexually reproducing population increase more slowly than asexual ones,
therefore reducing the chance of resource competition
Sexual reproduction requires individuals to find each other, which facilitates dispersal to new
areas - Answers Sexual reproduction creates genetic diversity whereas asexual reproduction
creates genetic clones
What is the best definition of a complex life cycle?
A life cycle where an individual organism interacts with many other species
A life cycle in which an individual invests only in growth until it reproduces and dies
A life cycle involving at least two distinct morphological or physiological or habitat stages
A life cycle where a species reproduces more than once before it dies - Answers A life cycle
involving at least two distinct morphological or physiological or habitat stages
In some species, life cycles can involve both sexual and asexual reproduction
True
False - Answers True
How many chicks do birds tend raise each breeding season?
Three times the number of adult birds tending to the nest
The maximum number of eggs a female can produce, which depends on her fat stores
,The maximum number that they can successfully raise to fledglings
In most cases, birds will only raise two chicks per breeding season - Answers The maximum
number that they can successfully raise to fledglings
What is the key message from this figure?
(Check doc for image)
If a plant produces more seeds, each seed tends to be smaller
Most plants produce a pretty large number of pretty large seeds
Only a few species produce large seeds
Plants can produce lots of seeds if they have enough energy stores - Answers If a plant
produces more seeds, each seed tends to be smaller
If a species is large, long-lived, provides parental care to its young, and produces large offspring,
it would be classified as:
K-selected
r-selected - Answers K-selected
Select all life-history trade offs:
Offspring number vs. parental growth
Offspring number vs. offspring size
Caring for offspring vs. reproducing again
Offspring size vs. parental survival - Answers Offspring number vs. parental growth
Offspring number vs. offspring size
Caring for offspring vs. reproducing again
Offspring size vs. parental survival
Imagine you have two plant populations, one growing in the Arctic and one growing in San
Francisco. How will their life-history strategies differ?
The population in San Francisco will grow and reproduce faster because it is warmer and wetter
there
The two plants are from the same species so their life-history will be the same because
evolution selected it
, In the Arctic, young plants will grow, flower, and seed much faster. In San Francisco, they will be
slower and potentially even survive for multiple years. - Answers In the Arctic, young plants will
grow, flower, and seed much faster. In San Francisco, they will be slower and potentially even
survive for multiple years.
I am a just-metamorphosed clownfish joining an anemone where there are five other adults of
different sizes. What should I do?
Mate with all other individuals in the anemone to increase my fitness
Limit my growth to not be too close in size to the next biggest because they might kill me or
evict me from the anemone
Grow as quickly as possible to become a female and the dominant fish in the anemone -
Answers Limit my growth to not be too close in size to the next biggest because they might kill
me or evict me from the anemone
What is the difference between proximate and ultimate causes of behavior?
Proximate causes are the short-term reason, whereas ultimate causes pertain to the adaptive
significance of the behavior
Proximate causes pertain to the adaptive significance of a behavior and ultimate causes are the
immediate reason a behavior happened - Answers Proximate causes are the short-term reason,
whereas ultimate causes pertain to the adaptive significance of the behavior
What is the core principle of optimal foraging theory?
Animals forage in a way that minimizes predation risk
Animals forage in a way that maximizes their energy intake
Animals forage in a way that reduces competition for food
Animals forage in a way that maximizes energy intake per unit of time spent foraging - Answers
Animals forage in a way that maximizes energy intake per unit of time spent foraging
Which size group is best for group members?
Large
Small
Intermediate - Answers Intermediate
What is a key determinant of monogamous vs. polyandrous/polygynous mating systems?
Polyandry/polygyny involve little competition for mates within the non-choosy sex
Which of the below is a key event in an organism's life history?
Survival to adulthood
Reproduction
Metamorphosis
All of the options are correct - Answers All of the options are correct
What the key advantage of sexual reproduction compared to asexual reproduction?
Sexual reproduction creates genetic diversity whereas asexual reproduction creates genetic
clones
Unequal contribution to gametes (isogamy) in sexual reproduction means that reproduction is
less costly for one sex in a population, which can stop the population from going extinct
All else equal, sexually reproducing population increase more slowly than asexual ones,
therefore reducing the chance of resource competition
Sexual reproduction requires individuals to find each other, which facilitates dispersal to new
areas - Answers Sexual reproduction creates genetic diversity whereas asexual reproduction
creates genetic clones
What is the best definition of a complex life cycle?
A life cycle where an individual organism interacts with many other species
A life cycle in which an individual invests only in growth until it reproduces and dies
A life cycle involving at least two distinct morphological or physiological or habitat stages
A life cycle where a species reproduces more than once before it dies - Answers A life cycle
involving at least two distinct morphological or physiological or habitat stages
In some species, life cycles can involve both sexual and asexual reproduction
True
False - Answers True
How many chicks do birds tend raise each breeding season?
Three times the number of adult birds tending to the nest
The maximum number of eggs a female can produce, which depends on her fat stores
,The maximum number that they can successfully raise to fledglings
In most cases, birds will only raise two chicks per breeding season - Answers The maximum
number that they can successfully raise to fledglings
What is the key message from this figure?
(Check doc for image)
If a plant produces more seeds, each seed tends to be smaller
Most plants produce a pretty large number of pretty large seeds
Only a few species produce large seeds
Plants can produce lots of seeds if they have enough energy stores - Answers If a plant
produces more seeds, each seed tends to be smaller
If a species is large, long-lived, provides parental care to its young, and produces large offspring,
it would be classified as:
K-selected
r-selected - Answers K-selected
Select all life-history trade offs:
Offspring number vs. parental growth
Offspring number vs. offspring size
Caring for offspring vs. reproducing again
Offspring size vs. parental survival - Answers Offspring number vs. parental growth
Offspring number vs. offspring size
Caring for offspring vs. reproducing again
Offspring size vs. parental survival
Imagine you have two plant populations, one growing in the Arctic and one growing in San
Francisco. How will their life-history strategies differ?
The population in San Francisco will grow and reproduce faster because it is warmer and wetter
there
The two plants are from the same species so their life-history will be the same because
evolution selected it
, In the Arctic, young plants will grow, flower, and seed much faster. In San Francisco, they will be
slower and potentially even survive for multiple years. - Answers In the Arctic, young plants will
grow, flower, and seed much faster. In San Francisco, they will be slower and potentially even
survive for multiple years.
I am a just-metamorphosed clownfish joining an anemone where there are five other adults of
different sizes. What should I do?
Mate with all other individuals in the anemone to increase my fitness
Limit my growth to not be too close in size to the next biggest because they might kill me or
evict me from the anemone
Grow as quickly as possible to become a female and the dominant fish in the anemone -
Answers Limit my growth to not be too close in size to the next biggest because they might kill
me or evict me from the anemone
What is the difference between proximate and ultimate causes of behavior?
Proximate causes are the short-term reason, whereas ultimate causes pertain to the adaptive
significance of the behavior
Proximate causes pertain to the adaptive significance of a behavior and ultimate causes are the
immediate reason a behavior happened - Answers Proximate causes are the short-term reason,
whereas ultimate causes pertain to the adaptive significance of the behavior
What is the core principle of optimal foraging theory?
Animals forage in a way that minimizes predation risk
Animals forage in a way that maximizes their energy intake
Animals forage in a way that reduces competition for food
Animals forage in a way that maximizes energy intake per unit of time spent foraging - Answers
Animals forage in a way that maximizes energy intake per unit of time spent foraging
Which size group is best for group members?
Large
Small
Intermediate - Answers Intermediate
What is a key determinant of monogamous vs. polyandrous/polygynous mating systems?
Polyandry/polygyny involve little competition for mates within the non-choosy sex
