Spermatophytes

Question 1

Characteristics of Spermatophytes (Seed Plants)

Answer 1

1. Heterosporous
2. Retention of Megaspore and female gametophyte on sporophyte
3. Ovule
4. Pollen
5. Seeds

Question 2

Ovule

Answer 2

An integumented megasporangium bearing a single functional megaspore

• Endosporic (inside spore wall)
• Nucellus
• Integuments
• Micropyle

Question 3

Nucellus

Answer 3

The modified, fleshy megasporangium

-Ovule

Question 4

Integuments

Answer 4

Flaps of sporophyte tissue covering nucellus

-Ovule

Question 5

Micropyle

Answer 5

An opening through integuments

-Ovule

Question 6

Meiosis

Answer 6

Occurs in nucellus

• produces 1 megaspore (3 abort)
• Megaspore germinates

Question 7

Female gametophyte

Answer 7

Several archegonia

-No neck

Question 8

Seed

Answer 8

Mature ovule bearing an embryo

• Seed coat
• Nutritive tissue
• Embryo

Question 9

Embryo

Answer 9

Inside of seed

• Baby sporophyte
• Cotyledons (seed leaves)
• Apical meristem
• Hypocotyle (stem)
• Radicle Root

Question 10

Generations in Seeds

Answer 10

1. Embryo
2. Nutritive tissue (maternal gametophyte)
3. Seed coat (maternal sporophyte)

Question 11

Pollen

Answer 11

Endosporic Male gametophyte plant

• Prothallial cells
• Generative cell
• Tube cell-makes pollen tube

Question 12

Pollen wall

Answer 12

Elaborately sculptured outer layer and coated w/ sporopollenin
-Pores-doors through which pollen tubes germinate

Question 13

Pollen Variation

Answer 13

Dif size, shape, structure, sculpting

-Pollen must land on receptive surface of right species to germinate

Question 14

Steps of Seed Plant Reproduction

Answer 14

1. Pollination-Pollen born to ovule
2. Pollen Germination
3. Syngamy-Embryo created

Question 15

Gymnosperm Characteristics

Answer 15

• Naked seeds
• Polyembryony
• Tracheids but no vessel elements

Question 16

Polyembryony

Answer 16

Only 1 embryo in a seed survives out of the many formed

-Gymnosperms

Question 17

Zooidogamy

Answer 17

“High Drive”

• Ancestral
• Pollen tube releases sperm into sperm lake
• Multiflagellate sperm swim to egg

Question 18

Siphonogamy

Answer 18

“Conveyor Belt”

• Derived
• Pollen tube grows toward ovule
• Pierces egg and releases naked sperm into egg

Question 19

Zooidogamous Gymnosperms

Answer 19

Ancestral

• Cycadophyta
• Ginkophyta

Question 20

Siphonogamous Gymnosperms

Answer 20

Derived

• Coniferophyta
• Gnetophyta

Question 21

Cycadophyta

Answer 21

Sp Div-7th
Eco Div- Tropical and relictual
-Leaves resemble palm trees
-Circinate vernation
-Coralloid roots
-Strobili
-Zooidogamy

Question 22

Coralloid Roots

Answer 22

Symbiotic relationship b/w cycad root and nitrogen fixing bacteria

• Bacteria provides nitrogen
• Cycadophyta

Question 23

Ginkgophyta

Answer 23

Sp Div-10th
Only 1 species!
Eco Div-Mountains of China and common landscape 
-Zooidogamy
-Fan-like leaves 
-Ovules on shoots

Question 24

Coniferophyta

Answer 24

Sp Div-6th
Eco Div-widespread, dominant in taiga/boreal forests and east TX
-Very large w/ needles
-Resin ducts
-Compound female cones with bract-scale complexes
-Siphonogamy

Question 25

Resin Ducts

Answer 25

Cavity lined w/ secretary parenchyma

• Resin made of turpentine and Rosin (wax)
• When duct is broken turpentine evaporates and resin dries which traps pathogens and seals opening
• Coniferophyta

Question 26

Strobili

Answer 26

Bear reproductive structures

-Microstrobili bear microsporangia and megastrobili bear ovules

Question 27

Conifer Pollen

Answer 27

Produced in microstrobili

-Have wings so dispersed by wind

Question 28

Gnetophyta

Answer 28

Sp Div-9th

• Have some angiosperm-like features (ovules)
• Siphonogamy
• Primative vessels (embryo sacs)

Question 29

Ephedra

Answer 29

• Gnetophyta

- Source of ephedrine, used to treat asthma, allergies, source of meth

Question 30

Megastrobili

Answer 30

Ovules born on scale (hard, modified branches) in axil of bracts