Gymnosperms

Question 1

What do seeds allow?

Answer 1

plants to reproduce and propagate in drier terrestrial environments

Question 2

What does a seed contain?

Answer 2

a fertilized embryo and its food supply, which are surrounded in a protective coat

Question 3

What is pollen?

Answer 3

structure allowing sperm to be transported great distance without using water

Question 4

What are common characteristics of seed plants?

Answer 4

highly reduced gametophytes
heterospory
ovules
pollen

Question 5

How does the reduced gametophyte increase the survival of a seed plant?

Answer 5

allows the haploid gametophyte to be protected from environmental stresses (drying out)
vulnerable haploid gametophyte is nourished directly from the parent sporophyte, rather than fend for itself

Question 6

What is heterospory?

Answer 6

seed plants will make either female or male gametophytes (but not bisexual)

Question 7

What are the two types of spores?

Answer 7

microsporangia: male spores (small), give rise to many microspores - male gametophytes
megasporangia: female spores (large), give rise to few megaspores - female gametophytes

Question 8

What is integument?

Answer 8

a layer of sporophyte tissue, which envelops and protects the megasporangia, becoming the protective coat

Question 9

What is the ovule?

Answer 9

entire structure including the integument, megasporangia, and megaspore

Question 10

What is developed inside pollen?

Answer 10

microspores, which house male gametophytes

Question 11

What is pollination?

Answer 11

transfer of pollen to the part of plant containing ovules

Question 12

What is the pollen tube?

Answer 12

present in both angio and gymnosperms

grows into the ovule, discharging two sperm into the female gametophyte

Question 13

What evolutionary advantages did seeds confer?

Answer 13

allowed seed plants to reproduced and propagate in drier environments, due to water retention and protection
seeds can remain dormant for days to years, until favorable conditions arrive for germination
provide sturdy casing for transport long distances by water, wind, and animals

Question 14

What are the four general groups of gymnosperms?

Answer 14

ginkophyta
cycadophyta
gnetophyta
coniferophyta

Question 15

Describe Ginkophyta.

Answer 15

one species: Ginko biloba
have flagellated sperm
found naturally in moist areas
have a high tolerance to air pollution, so they are often planted in urban areas

Question 16

Describe Cycadophyta.

Answer 16

cycads or sago plants
palm-like, but not actual palms
seeds are produced in large cones
have flagellated sperm
thrived during the mesozoic, but relatively few members exist today

Question 17

Describe Gnetophyta.

Answer 17

3 genera: gnetum, ephedra, welwitschia
some tropical, while others live in desert
have giant ovule cones
live to be very old
look very different from each other, but DNA data shows that they are related

Question 18

Describe Coniferophyta.

Answer 18

conifers: include members like pines, firs, redwoods, spruce, cypress
many have needle like leaves that help prevent water loss
most are evergreens, which retain their leaves year-round
large forests on earth are mostly conifers: some of the largest and tallest organisms