Answers to Pg 71. 1-5

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Pg 71 1-5
1. Describe the fundamental cycle that allows all plants to reproduce sexually.
A. meiosis produces gametes
B. a male gamete combines with a female gamete
C. a zygote is produced and develops into an embryo
D. the embryo develops through mitosis and cell division into a mature offspring
2. Explain what the following have in common and how they differ:
A. The pistil and the stamen are both reproductive organs. The pistil is the female
reproductive organ producing eggs and the pistil is the male reproductive organ
producing sperm or pollen grains.
B. The flower and the cone both contain the plant’s reproductive organs. The flower and
the cone both have structures that produce pollen grains and ovules. The flower is found
in the angiosperms and the cone is found in the gymnosperms.
C. Both angiosperms and gymnosperms are capable of producing seeds. The seeds of the
angiosperms are produced inside flowers; where as the seeds of gymnosperms are
produced inside cones. In some gymnosperms, pollen and ovules are produced on cones
in separate trees.
D. Both seeds and spores are reproductive units; they are necessary to complete the life
cycle of seed-producing and non-seed-producing plants, respectively.
3. What is the function of pollination? Explain what pollination alone does not ensure
successful reproduction.
The function of pollination is to ensure the transfer of pollen from the anther to the
stigmas of flowers for fertilization. In order for successful reproduction to ovule,
however, the fertilized plant must produce seeds and successfully disperse those seeds.
The seeds must also land in a suitable habitat so they can germinate and grow into mature
plants capable of reproduction.
4.
Explain why seeds can be referred to as “plants in storage”.
A. Seeds can be referred to as “plants in storage” because they contain all the necessary
precursors for a typical plant; the leaf, stem, and root are all found within the embryo of
the seed.
Can spores also be though of as plants in storage?
B. Spores cannot be though of as plants in storage because they merely develop into
sperm and egg-producing gametophytes that, in turn, form new plants.
5.
Can a gamete develop into a compete plant by itself, without fertilization?
A. A gamete cannot develop into a complete plant by itself without fertilization because
it has not undergone sexual reproduction. A zygote must form by the union of a male and
female gamete to develop into an embryo.
Can a spore develop into a compete plant by itself, without fertilization?
B. A spore, however, can develop into a plant body without fertilization if conditions are
appropriate.
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