Land Plants: Gymnosperm Diversity

Question 1

What are the 4 extant clades of gymnosperms?

Answer 1

Cyadophyta
Ginkgophyta
Coniferophyta
Gnetophyta

Question 2

What is the angiosperm extant clade?

Answer 2

Anthophyta

Question 3

What is a Megaphyll?

Answer 3

A leaf with two or more large veins either running parallel or branching apart and connected by a network of smaller veins

Question 4

What is wood?

Answer 4

secondary xylem (produced by the vascular cambium)

Question 5

What does the cork cambium produce?

Answer 5

bark

Question 6

What is Heterospory?

Answer 6

Sporophytes produce spores of two different sizes and sexes
The microspore (smaller) is male and the megaspore (large) is female

Question 7

What are two key features of seed plants?

Answer 7

continued gametophyte reduction adn airborne fertilization via pollen

Question 8

Where are gametophytes contained for gymnosperms and angiosperms?

Answer 8

in pollen and ovules

Question 9

What is ovule composed of in seed plants?

Answer 9

megasporangium (2n), female gametophyte or megaspore (n), and integument (2n)

Question 10

What is a sperm feature of cyads and ginkgos that conifers do not have?

Answer 10

they have motile sperm that can swim to the egg in the ovule
conifers do not and travels to egg in ovule via a pollen tube

Question 11

What is the seed?

Answer 11

a mature (fertilized0 ovule with a sporophyte (2n) embryo
it consists of a seed coat, embryo, and stored food

Question 12

What are the advantages of the seed?

Answer 12

increases offspring survival
resuslts in higher germination raytes and seedling establishment than plants that release ‘naked’ zygotes and spores

Question 13

How does the seed increase offspring survival?

Answer 13

physically protects the enclosed embryo
prevents the embryo from desiccation
source of nourishment for the embryo

Question 14

What are the features of both angiosperms and gymnosperms?

Answer 14

micropyle, nucleus, megasporocyte, integument presence, ovule

Question 15

What is the difference between the integuments in angiosperms and gymnosperms?

Answer 15

in angiosperms it is a double-layer
gymnsperms only a single-layer

Question 16

What are features unique to the Angiosperms?

Answer 16

flowering
style, stamen (anther and filament), ovary wall, Funiculus

Question 17

What are Cycadophyta (cyads)?

Answer 17

Palm-like plants in tropics and subtropics
leaves clustered at top of woody tunk
Florida one species Zamia pumila

Question 18

What is difference between palm trees and cyads?

Answer 18

presence of cones instead of flowers differentiates cyads to gymnosperms

Question 19

What does it mean to be Dioecious?

Answer 19

separate male and female cone-bearing plants
Cyads are Dioecious

Question 20

How do cyads do pollination?

Answer 20

insects attracted by chemical signals in cones

Question 21

after fertilization what is produced by cyads? for what purpose?

Answer 21

brightly coloured, fleshy seeds, attracting birds and mammals for dispersal

Question 22

What is the only species of Ginkgophyta? where found?

Answer 22

Ginkgo biloba
preserved on temple grounds in China and Japan
introduced in North America in late 1700s not wild

Question 23

What is a feature of Ginkgos that make it suitable for urban parks and city streewts?

Answer 23

it is resistant to air pollution

Question 24

What are features of seeds etc. of Ginkgos?

Answer 24

dioecious, 2 ovules per short short (usually one matures), fleshy seed coat, male cones clustered at tip of short shoots

Question 25

Which clade os Gentophyta sister to?

Answer 25

conifers

Question 26

what are the 3 extant genera of gnetophyta?

Answer 26

gnetum
ephedra
welwitschia

Question 27

What platns do Coniferophyta include?

Answer 27

pine, fir, spruce, redwoods …

Question 28

Where are conifers dominant?

Answer 28

in temperate and mountain forests

Question 29

What are most conifers? meaning?

Answer 29

evergreen so keep needles all year round

Question 30

What is a unique feature of conifer xylem?

Answer 30

consists almost entirely of tracheids, resulting in wood that is trong fro its weight with relatively uniform mechanical properties

Question 31

What are leaves like in the pine family?

Answer 31

reduced in bundles 1 to 8 leaves, needles like megaphylls: 2 veins

Question 32

What are advantages of Pine leaves?

Answer 32

adapted for growth in dry habitats
thick cuticle (waxy)
hypodermis
stomata in pits
mesophyll cells with wall ridges
Endodermis

Question 33

What is hypodermis?

Answer 33

compact layers of cells below epidermis

Question 34

What do wall ridges do?

Answer 34

increase surface area

Question 35

What makes up the bark in pine secondary growth?

Answer 35

secondary phloem and peridem

Question 36

What is the peridem derived from?

Answer 36

outer layer of cortex