UPDATED ACTUAL Exam Questions and
CORRECT Answers
Why are plants important for humans? - CORRECT ANSWER - 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 ANSWER - 475 million
what changed when plants colonized land (in terms of the environment) - CORRECT
ANSWER - 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 ANSWER - There is less
competition for light
What factors made it difficult for a lineage of algae to invade land? - CORRECT
ANSWER - cells might dry out, less physical support, more difficult for sperm to reach
egg
what type of algae moved to land? - CORRECT ANSWER - green algal clade
why do we think green algae "became" plants? - CORRECT ANSWER - 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
ANSWER - lived in fresh water, did not use swimming gametes, sporopollenin,
mycorrhizal associations
,preadaptation - CORRECT ANSWER - a trait that was already present and allowed a
major ecological transition
How did living in fresh water help charophytes jump to land? - CORRECT ANSWER -
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 ANSWER - 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 ANSWER - 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 ANSWER - covers spores and is extremely resistant to water
loss and UV radiation
first plants to make mycorrhizal associations - CORRECT ANSWER - charophytes, the
association helped them get nutrients
Cuticle - CORRECT ANSWER - 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 ANSWER - to allow for gas exchange
how many spores does a charophyte doing zygotic meiosis make for each fertilization event -
CORRECT ANSWER -4
3 major adaptations shared by all land plants - CORRECT ANSWER - cuticle,
pores/stomata, and embryo
, Alternation of generations - CORRECT ANSWER - 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 ANSWER - the haploid life stage that makes the gametes (eggs
and sperm) by mitosis
sporophytes - CORRECT ANSWER - the diploid life stage that makes the spores by
meoisis
embryo - CORRECT ANSWER - a young sporophyte that is nourished by maternal tissue
When does meiosis occur in the land plant life cycle? - CORRECT ANSWER - during the
formation of the spores by the sporophyte
What plant groups make up the bryophytes - CORRECT ANSWER - liverworts, mosses,
and hornworts
main characteristics of byrophytes - CORRECT ANSWER - nonvascular, very short, live
in moist areas, the gametophyte is the dominant lifestage
What plants have pores rather than stomata - CORRECT ANSWER - liverworts
what plants started the trend towards larger sporophytes - CORRECT ANSWER -
hornworts - the gametophyte is dominant but the sporophyte lives long as well
how do the life stages work in bryophytes - CORRECT ANSWER - the gametophytes are
dominant and the sporophyte depends on the gametophyte