Gymnosperms Lab Exam 2 Flashcards Preview

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Flashcards in Gymnosperms Lab Exam 2 Deck (38)
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1
Q

Seedless plants reproduce via

A

Spores

2
Q

Seed plants reproduce via

A

Seeds

3
Q

a structure in which the embryo (the young sporophyte) is shed from the parent plant, enclosed within a resistant coat, together with a supply of food that aids its establishment

A

Seed

4
Q

Which plants are the majority of seed plants

A

Extant plants

5
Q

Consist of an embryo

A

Seed

6
Q

Seeds stores food which is called the

A

Endosperm

7
Q

Modern seed plant the ovule consist of a nucellus envelope by one or two ____ with a ____

A

integuments with a micropyle

8
Q

a micropyle is also called

A

apical opening

9
Q

When fertile the nucellus contains a megagametophyte composed of _____ and ____

A

nutritive tissue and archegonia

10
Q

After fertilization the integuments develop into a

A

seed coat; a seed is formed

11
Q

A megaspore retained within a fleshy megasporangium

A

nucellus

12
Q

Do seed plants require water for fertilization?

A

No

13
Q

Development of the embryo (young sporophyte) within the ___retained within the ____

A

megagametophyte retained within megasporangium

14
Q

The seed habit arose by 365 million years ago via fusion of vegetative tissues around the ____

A

megasporangium

15
Q

This additional protective layer is called an

A

integument

16
Q

The integument has a small opening called

A

Micropyle

17
Q

Fertilization takes place through this part of the seed

A

Micropyle

18
Q

an integumented megasporangium

A

Ovule

19
Q

Following fertilization the integument will become the

A

seed coat

20
Q

The pollen is shed at this stage and it carried by the wind to an immature ____

A

megastrobilus

21
Q

During the spring pollination season the megastrobili (female cones) have their cone scales ___

A

Open

22
Q

The pollen in the wind is caught and held by a sticky secretion. As the secretion dries up the pollen is drawn into the ____. The cone scales then grow together

A

micropyle

23
Q

The pollen tube begins to digest through the ____ towards the developing megagametophyte

A

nucellus

24
Q

The pollen tube begins to digest through the nucellus towards the developing

A

megagametophyte

25
Q

Twelve months after pollination the generative cell divides to form a

A

sterile cell and a spermatogenous cell

26
Q

Megastrobili (female cones) are ___ than the microstrobili.

A

Larger

27
Q

A pair of ovules sit on top of a ___ which is subtended by a sterile bract.

A

seed-scale complex

28
Q

Each ovule contains a _____ surrounded by a thick integument with an opening (micropyle) facing inward

A

multicellular nucellus

29
Q

Each nucellus contains a megasporocyte (megaspore mother cell) which undergoes meiosis to produce

A

Four haploid cells

30
Q

Three degenerate and the remaining one develops into the ___ over a six month period.

A

megagametophyte

31
Q

At 13 months after pollination, inside the megagametophyte, a large number of free nuclear divisions take place, forming 2,000 free nuclei. Then cell walls form to make solid tissue. This gametophytic tissue will become the

A

stored food inside the mature seed

32
Q

15 months after pollination 2 - 3 archegonia, each containing an egg, form. At this time the pollen tube reaches the archegonia and it discharges both sperm nuclei into the archegonia. One sperm ____ the egg, the other ___

A

fertilizes and the other degenerates

33
Q

As the developing zygote divides to form the embryo ____ of cells are produced.

A

four tiers

34
Q

These form suspensors which push the developing embryo deep into the ______. Simultaneously the integument forms the seed coat

A

gametophyte tissue

35
Q

Developing stored food

A

Gametophyte tissue

36
Q

As the developing zygote divides to form the embryo four tiers of cells are produced. These form ____ which push the developing embryo deep into the gametophyte tissue (developing stored food). Simultaneously the integument forms the seed coat

A

suspensors

37
Q

push the developing embryo deep into the gametophyte tissue (developing stored food). Simultaneously the integument forms the seed coat

A

Suspensors

38
Q

The seeds mature and they are shed during the ____, when the cone scales open. Therefore if takes about 2 1/2 years from pollination to the shedding of seeds

A

second autumn