Next major evolutionary advance:

1
Next major evolutionary advance
These ?
replace spores as the major agents of plant repro
- duction
2
A seed is a plant embryo having a supply of food
and a protective covering around it. The latter
two allow the seed to survive until conditions in
the environment are favorable for its germination.
3
Seed plants evolved from spore-producing
plants about 350 106 years ago
4
Taxonomy of seed plants

• GYMNOSPERMS
• Cycadophyta
• Gingkophyta
• Gnetophyta
• Coniferophyta

• ANGIOSPERMS
• Anthophyta

5
ANTHOPHYTES evolved from GYMNOSPERMS about 1.3
108 years ago
?
6
Coniferophyta plants bearing cones
They are the most recent of gymnosperms to have
evolved
7
Characteristics of Conifers

• evergreen
• needles for leaves
• non-deciduous (because of their shape)
• naked seeds
• genus Sequoia contains the largest of all living
  organisms today!

8
(No Transcript)
9
A brief little movie on the gymnosperm life cycle
http//images.google.com/imgres?imgurlhttp//www.
zo.utexas.edu/faculty/sjasper/images/30.10a3.jpgi
mgrefurlhttp//www.zo.utexas.edu/faculty/sjasper/
bio213/plants.htmlh526w800sz70hlenstart5
1um1tbnid2xH6IAMVXEl9bMtbnh94tbnw143prev
/images3Fq3Dpine2Bpollen2B26start3D4026nds
p3D2026svnum3D1026um3D126hl3Den26sa3DN
10
(No Transcript)
11
ovulate cones
12
(No Transcript)
13
(No Transcript)
14
n.b., megaspore mother cell (2n)
15
(No Transcript)
16
pollen cones
17
(No Transcript)
18
(No Transcript)
19
pollen grains
(male gametophytes or microgametophytes)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
what will these develop into?
mature pine seeds
26
(No Transcript)
27
early pine seedling
?
28
ANTHOPHYTA flower-bearing plants
29
Today, there are 235,000 species of
anthophytes, compared to 700 species of
gymnosperms. What does this suggest about
the evolution of flowers and fruits for
reproduction and dispersal??
30
Flower growth movie
http//images.google.com/imgres?imgurlhttp//www.
zo.utexas.edu/faculty/sjasper/images/30.10a3.jpgi
mgrefurlhttp//www.zo.utexas.edu/faculty/sjasper/
bio213/plants.htmlh526w800sz70hlenstart5
1um1tbnid2xH6IAMVXEl9bMtbnh94tbnw143prev
/images3Fq3Dpine2Bpollen2B26start3D4026nds
p3D2026svnum3D1026um3D126hl3Den26sa3DN
31
Flowers are organs of reproduction
32
(No Transcript)
33
(male)
(female)
34
(No Transcript)
35
Cross-section through an anther
36
various anthophyte pollens
37
vector-driven cross-pollination
38
Pollination Movie
http//images.google.com/imgres?imgurlhttp//i1.t
rekearth.com/photos/9954/pollination.jpgimgrefurl
http//tumi-educational-resources.org/Educational
25202520Videos.htmh523w800sz162hlenstar
t4tbnid6m2nd01bAyQAZMtbnh93tbnw143prev/i
mages3Fq3Dpollination26gbv3D226svnum3D1026h
l3Den26sa3DX
39
germinating pollens
40
(No Transcript)
41
(No Transcript)
42
(No Transcript)
43
(No Transcript)
44
eight cell stage
mature mega- gametophytes
45
?
this stage is unique to
anthophytes
46
anthrophyte fertilization
47
anthrophyte fertilization
48
(No Transcript)
49
(No Transcript)
50
(No Transcript)
51
anthophyte seed anatomy
52
?
seed germination
53
(No Transcript)