BIOLOGY 152 EXAM 2 PLANT
PHYSIOLOGY WITH CORRECT
ANSWERS 2025
Why are plants important for humans? correct answers >>
Some examples include oxygen, shade, food, beauty (products
and to look at), preservatives, oils, the ozone layer
Plants caame to land about _____ years ago correct answers
>> 475 million
what changed when plants colonized land (in terms of the
environment) correct answers >> created soil (it was rock
prior to this), changed the distribution of nutrients in the oceans,
and reduced the CO2 concentration while increasing the O2
concentration in the atmosphere (this created the ozone layer)
Why was it beneficial for algae to invade land? correct answers
>> There is less competition for light
What factors made it difficult for a lineage of algae to invade
land? correct answers >> cells might dry out, less physical
support, more difficult for sperm to reach egg
what type of algae moved to land? correct answers >> green
algal clade
,why do we think green algae "became" plants? correct
answers >> green algae and plants have cellulose cell wall,
chorophyll a and b, and two anterior flagella while red algae don't
What were pre adaptations of charophytes that may have helped
them move to land correct answers >> lived in fresh water,
did not use swimming gametes, sporopollenin, mycorrhizal
associations
preadaptation correct answers >> a trait that was already
present and allowed a major ecological transition
How did living in fresh water help charophytes jump to land?
correct answers >> the water on land (in the form of lakes and
rain) would have been fresh
How did using spores help charophytes move to land? correct
answers >> land plants cannot use swimming gametes because
they are not submerged in water, therefore spores that disperse
through wind would have been advantageous
Zygotic meiosis correct answers >> The zygote (n)
undergoes meiosis to create spores (n) which undergo mitosis to
create and adult (n). The adult makes either sperm or eggs (n)
which combine to make the zygote.
sporopollenin correct answers >> covers spores and is
extremely resistant to water loss and UV radiation
, first plants to make mycorrhizal associations correct answers
>> charophytes, the association helped them get nutrients
Cuticle correct answers >> waxy covering of all above-
ground structures in the plant that prevents water loss but also
prevents gas exchange
Why do plants need stomata or pores correct answers >> to
allow for gas exchange
how many spores does a charophyte doing zygotic meiosis make
for each fertilization event correct answers >> 4
3 major adaptations shared by all land plants correct answers
>> cuticle, pores/stomata, and embryo
Alternation of generations correct answers >> A zygote (2n)
undergoes mitosis to create a sporophyte (2n) which then
undergoes meiosis to create spores (n). The spores undergo
mitosis to create the gametophyte (n) which then undergo mitosis
to create eggs/sperms (the gametes, n) which will come together
to make the zygotes.
gametophyte correct answers >> the haploid life stage that
makes the gametes (eggs and sperm) by mitosis
sporophytes correct answers >> the diploid life stage that
makes the spores by meoisis
PHYSIOLOGY WITH CORRECT
ANSWERS 2025
Why are plants important for humans? correct answers >>
Some examples include oxygen, shade, food, beauty (products
and to look at), preservatives, oils, the ozone layer
Plants caame to land about _____ years ago correct answers
>> 475 million
what changed when plants colonized land (in terms of the
environment) correct answers >> created soil (it was rock
prior to this), changed the distribution of nutrients in the oceans,
and reduced the CO2 concentration while increasing the O2
concentration in the atmosphere (this created the ozone layer)
Why was it beneficial for algae to invade land? correct answers
>> There is less competition for light
What factors made it difficult for a lineage of algae to invade
land? correct answers >> cells might dry out, less physical
support, more difficult for sperm to reach egg
what type of algae moved to land? correct answers >> green
algal clade
,why do we think green algae "became" plants? correct
answers >> green algae and plants have cellulose cell wall,
chorophyll a and b, and two anterior flagella while red algae don't
What were pre adaptations of charophytes that may have helped
them move to land correct answers >> lived in fresh water,
did not use swimming gametes, sporopollenin, mycorrhizal
associations
preadaptation correct answers >> a trait that was already
present and allowed a major ecological transition
How did living in fresh water help charophytes jump to land?
correct answers >> the water on land (in the form of lakes and
rain) would have been fresh
How did using spores help charophytes move to land? correct
answers >> land plants cannot use swimming gametes because
they are not submerged in water, therefore spores that disperse
through wind would have been advantageous
Zygotic meiosis correct answers >> The zygote (n)
undergoes meiosis to create spores (n) which undergo mitosis to
create and adult (n). The adult makes either sperm or eggs (n)
which combine to make the zygote.
sporopollenin correct answers >> covers spores and is
extremely resistant to water loss and UV radiation
, first plants to make mycorrhizal associations correct answers
>> charophytes, the association helped them get nutrients
Cuticle correct answers >> waxy covering of all above-
ground structures in the plant that prevents water loss but also
prevents gas exchange
Why do plants need stomata or pores correct answers >> to
allow for gas exchange
how many spores does a charophyte doing zygotic meiosis make
for each fertilization event correct answers >> 4
3 major adaptations shared by all land plants correct answers
>> cuticle, pores/stomata, and embryo
Alternation of generations correct answers >> A zygote (2n)
undergoes mitosis to create a sporophyte (2n) which then
undergoes meiosis to create spores (n). The spores undergo
mitosis to create the gametophyte (n) which then undergo mitosis
to create eggs/sperms (the gametes, n) which will come together
to make the zygotes.
gametophyte correct answers >> the haploid life stage that
makes the gametes (eggs and sperm) by mitosis
sporophytes correct answers >> the diploid life stage that
makes the spores by meoisis
