Lecture 3 DA Flashcards Preview

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Flashcards in Lecture 3 DA Deck (57)
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1
Q

Are vascular plants sporophyte or gametophyte dominant?

A

Sporophyte.

2
Q

Do aerial plants have cutin or suberin?

A

Yes.

3
Q

How are vascular plants classified (2)?

A

By dispersal - via spores (unicellular) or by seeds (multicellular).
By sperm transport - H20 or pollen

4
Q

What are the seedless vascular plants (4)?

A

Ferns
Lycopodiophyta
Sphenophyte
Psilotophyta

5
Q

Do ferns have true leaves? What about lycopodiophyta?

A

Ferns have true leaves, lycopodiophyra dont, they have microfils.

6
Q

What are some advantages that ferns have over moss (2)?

A

Has vascular tissue

Dominant sporophytes

7
Q

What is the gametophyte of ferns like?

A

Small, and shortlived, can be photosynthetic.

Only a few cell layers thick.

8
Q

What is a source of carbon for fern gametophytes?

A

Has an association with a fungus, provides carbon.

9
Q

Do fern sperm require water?

A

Yes, needed to swim to the egg.

10
Q

When a fern egg is fertilised, where does it grow?

A

The zygote grows out of, and becomes independent from, the gametophyte.

11
Q

Do ferns grow on other plants?

A

Yes, but are not parasitic.

12
Q

What can be found on the underside of ferns? What do they release?

A

Structures called sori (sorus singular).

Produces haploid spores.

13
Q

What do fern spores do when released?

A

They germinate into gametophytes.

14
Q

Where are fern gametophytes found?

A

On the underside of fern leaves.

15
Q

What is a rhizome, and what grows out of it?

A

Its an underground modified stem. True stems shoot out of it.

16
Q

What are pteridophytes?

A

Ferns and allies.

17
Q

Where are xylem and phloem found relative to each other?

A

Phloem is found on the outer edge, whereas xylem is on the inside.

18
Q

What is the diameter of xylem relative to phloem?

A

Xylem has a larger diameter.

19
Q

What did xylem and phloem development allow for in vascular plants? What is an advantage of this?

A

Allowed for crown development. Meant their leaves could be out of the reach of herbivores.

20
Q

What is secondary thickening? What does it do?

A

Cells lay down a primary wall. Within it, they lay down a secondary wall, mainly lignin. Gives support and rigidity.

21
Q

What is wood moslty made of?

A

Dead xylem cells.

22
Q

What are the main groups of pteridophytes (5)?

A
Fork ferns
True ferns
Lycopods
Horsetails
Progymnosperms
23
Q

What were the first land plants?

A

Fork ferns.

24
Q

Do fork ferns have leaves or roots?

A

They lack true leaves or roots.

25
Q

How are fork ferns branched? Are they vascular?

A

Dichotomously branched. They are vascular.

26
Q

What are the leaves of true ferns called? Are they true leaves?

A

Has true leaves called fronds. They are large, called megaphylls.

27
Q

How are true fern leaves divided? How many veins do they have?

A

Pennately divided. Are multiveined.

28
Q

What shape do true ferns have?

A

Circinnate vernation. Theyre uncoiling.

29
Q

What are lycopods like?

A

Small leaved, with single veins.

30
Q

What are horsetails like?

A

Whorled leaves, that are silicified. They have ribbed stems.

31
Q

Do progymnosperms exist?

A

No, theyre extinct.

32
Q

What are progymnosperms like?

A

Are spore-forming trees with fern-like leaves. They have gymnosperm-like wood.

33
Q

Can leaves be specialised? What is the difference between sterile and fertile leaves?

A

Yes, ferns can specialise their leaves.

Some are sterile, which are true leaves, or fertile, which are false leaves.

34
Q

What is an annulus, and what are they found on?

A

Most true ferns have them, found on sporangia. Has thick cell walls. Thicker on the inside than the outside and is water-filled.

35
Q

What is a prothallus?

A

Gametophyte.

36
Q

What does a prothallus have on it?

A

Archegonia and antheridia which produce gametes.

37
Q

What do sporangia have in them besides an annulus?

A

Spores.

38
Q

Where can sporangia be found?

A

Axial surface of leaves.

39
Q

What is meant by homo and heterosporous?

A

Homosporous - only one type of spore majority. Heterosorous have more than one.

40
Q

What is a megaspore?

A

Large, produces only archegonia which make eggs.

41
Q

What is a microspore?

A

Small, only produce antheridia, which make sperm/antherozoids.

42
Q

What do megasporangia produce?

A

4 megaspores, 3 of which degenerate.

43
Q

What do microsporangia produce?

A

Masses of microspores/sperm.

44
Q

What do gymnosperms have that ferns and allies dont?

A

Advanced vascular tissue, particularly xylem.

45
Q

Are gymnosperms sporophyte or gametophyte dominant?

A

Sporophyte dominant. More highly reduced gametophytes.

46
Q

What is a female gymnosperm gametophyte enclosed in? What does this form later on?

A

Enclosed entirely in a sporophyte, produced in a sporangium. surrounded by an integument. Forms a protective seed coat in a mature seed.

47
Q

What is a male gymnosperm gametophyte enclosed in?

A

Pollen grain.

48
Q

Where do gymnosperm megaspores develop?

A

Within megasporangium.

49
Q

Where are gymnosperm reproductive organs found?

A

Within cones, male and female cones respectively.

50
Q

What features of gymnosperms makes them dessication resistant (5)?

A
Have a waxy surface (glaucous)
Are xeromorphic
Hard leaved (sclerophyllous)
Sunken stomata
Resin
51
Q

What are the classes of gymnosperms (3)?

A

Coniferopsida
Cycadopsida
Gnetopsida

52
Q

What is the living tissue of conifer wood like?

A

Only has living tissue in the core. Wood is layered in rings.

53
Q

Do gymnosperms produce fruit?

A

No, only angiosperms produce fruit. Some have false fruit (yew).

54
Q

What is a fruit?

A

Mature ovaries.

55
Q

What is the leaves and wood of Cycadopsida like? Is it cone bearing? What are its defences?

A

Leaves are palm-like.
Wood is manoxylic.
Is cone bearing.
Produces toxic alkaloids.

56
Q

Where are the pollen sacs and ovules of Cycadopsida found?

A

Male cones have pollen sacs at their base, which are the microsporangia, will produce microspores.
Female cone shave ovules within them.

57
Q

What is the reproduction of gymnosperms like in general?

A

They take a long time to develop.