Answers re: Assigned Textbook Work
p.399, # 4-7
4. Gymnosperms: = spermatophytes, produce naked seeds (usually found in cone)
Angiosperms: = spermatophytes, produce seeds enclosed in fruit
5. gymnosperms: mature pollen grains released  pollen grains have flaps/wings so they can be
carried by wind ; tips of female cones on tree point upwards  pollen lands on female cones  sap
from cone ensure pollen moves towards ovules where egg cells are
Angiosperms: wind/insect/bird/bat aid pollination: pollen transferred from anther to stigma  part of
pollen makes its way down through the style and sperm eventually reaches egg in ovule
6. gymnosperms: fertilization occurs when pollen fuses with egg cell  zygote forms  mitosis occurs
 embryo formed  embryo develops in ovule  seed forms
Angiosperms: fusion of pollen and egg  zygote formsmitosis occurs embryo forms embryo
develops in ovuleovule develops protective seed coat and is called seeds ovule and surrounding
tissue form fruit
7. two classes of angiosperms are monocots, which have one cotyledon(seed leaf), and dicots, which
have two cotyledons/seed leaves.
p. 402, #4, 10, 13, 14
4. have evolved thin, needle-like leaves that help the plants resist the harshness of hot, dry summers,
cold winters, and moderate rainfall; needles covered by waxy cuticles that help plants retain moisture;
have roots that extend over a wide surface area vs ones that penetrate deep into soil
10. a) provides offspring with different combinations of genes
b) leads to more variation among the offspring, allowing the species to adapt to a changing
environment
13. important source of raw materials for many commercial and industrial products (e.x. wood for
building and furniture construction, paper, varnishes, disinfectants, medicines); absorb rain water,
prevent soil erosion by water/wind
14. answers may vary