UNIT 8: SEED PLANTS

Study Questions  Lecture Outline
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KEY WORDS

Gymnosperms Nucellus Pedicel Placenta Antipodals Scutellum
Fascicles Dawn Redwood Peduncle Complete Endosperm Coleoptile
Sunken Stomates Juniper Sepals (calyx) Incomplete Seed Coat Coleorhiza
Hypodermis Gin Petals (corolla) Imperfect Integuments Suspensor
Transfusion Tissue Cycads Stamen Pistillate Pericarp Proembryo
Resin Ducts Ginkgo Anther-filament Adnation Epicotyl Globular
Terpentine Gnetophytes Androecium Tapetum Plummule Heart-Shape
Pollination Monocots Ovary-ovule Exine Hypocotyl Torpedo
Prothallial Cell Parallel Venation Pistil-stigma Sporopollenin Radicle After Ripening
Generative Cell Dicots Carpel Funicuius Cotyledons Hypogenous
Tube Cell Mistletoe Style Polar Nuclei Hilum Epigeous
Ovulate Cone Inflorescence Gunoecium Egg-suneraids Micropyle Radicle


STUDY QUESTIONS

UNIT 8: SEED PLANTS

1 - Primary structure which evolved and produced a source of stored food in    
		 gymnosperms

2 - Term which indicates the number of spores associated with the life cycle

3 - Meaning of gymnosperm

4 - General group of plants which have naked seeds

5 - Largest conifer

6 - Term for a group of needles

7 - Layer found just beneath the epidermis of pine needles

8 - Material produced in pine ducts

9 - Specialized cells which control water vapor loss

10 - Needle tissue which is involved in conduction between the mesophyll and
		vascular bundles

11 - Photosynthetic layer in pine needles

12 - Oldest gymnosperm

13 - Usually the smaller of the 2 gymnosperm cones

14 - Product produced from pine resin

15 - Tissue produced by the vascular cambium

16 - Conducting tissue found in pine bark

17 - Specialized layer which forms cork

18 - Cone where microsporocytes are formed

19 - Number of cells produced by meiosis

20 - Pollination agent in pine trees

21 - Opening between the integuments

22 - Cell which divides to form a stalk

23 - Cell in the pine life cycle

24 - Two pollen cells which degenerate

25 - Pollen cell which divides to form 2 sperms

26 - Time required for pollination and seed maturation in pine cones

27 - Specific tissue which gives rise to the pine megasporocycte

28 - Cell formed in fertilization

29 - First cell of the sporophyte generation

30 - Pine structure which contains the egg

31 - Cells formed directly by meiosis in the ovule

32 - Structure which forms the seed coat

33 - General term for multiple embryos

34 - Generation of tissue which serves as a food source in pine seeds

35 - Conifer which was discovered in China after identification from fossil    
		record

36 - Product derived from distillation of pine resin


LECTURE OUTLINE

UNIT 8: SEED PLANTS

A - Oldest seeds - Devonian period
   1 - Earliest seed plants - Progymnosperms
       a - major genus - Anchaeopteris, fossils only
   2 - Living divisions - Gymnosperms
       a - conifers - all woody, mostly evergreen
           EXAMPLE: of typical gymnosperm leaves, needle-like, occur in
                    bundles (fascicles)
       b - needle anatomy - adaptation for arid growth - thick cuticle,
           hypodermis sunken stomates, transfusion tissue, endodermis, resin
           ducts
       c - active bifacial vascular cambium
       d - life cycle - 
           -male cones - microsporocytes - meiosis - tetrad
           	 microspores produce 2 prothallial, 1 tube, 1 generative -
           	 generative forms 1 sterile stalk and 1 spermatagenous - the
           	 spermatogenous forms 2 sperm nuclei
           -female cones - 2 ovules per scale - meiosis,
             3 abort, 1 megaspore forms archegonia and nutritive tissue, 
             1 archegonium forms embryo - then embryo forms tiers of cells -
             One embryo develop cotyledons - enclosed in seed coat, contains
             food reserve

           Seeds - develop from ovule following fertilization - 
           2 years to develop
           Wings formed - assist wind pollination
       e - uses - resins, food, lumber, fiber
   3 - Cycads - 10 genera, 100 species; Zamia, dioecious cone bearing
   4 - Ginko - fan-shaped leaves, dicotomous venation, long and short shoots,
       Dioecious, survivor only 1 species in order, fleshy fruits rancid
   5 - Gnetophytes - 3 genera
       a - Gnetum, 
       b - Ephedra,
       c - Welwitschia
   6 - Angiosperms - Anthophyta
       a - two classes
           (1) monocots - grasses, lilies, orchids, palms
               flower parts 3's or multiples, 1 cotyledon,
               Parallel venation, scattered vascular bundles -
               No cambial activity
           (2) dicots - trees, herbaceous flower pars - 4 or 5's
               or multiples, netted venation, 2 cotyledons,
               woody-cambial activity
   7 - Non-photosynthetic
       a - parasitic - mistletoe, dodder form haustoria
       b - saprophyte - Indian pipes, beech drops - mycorrhizal
           associates
   8 - Photosynthetic - majority
       a - flowers - modified leaves, determinate, control - light,
           temperature
           (1) arrangement of flowers; inflorescence - umbel, peduncle
               single flowers
           (2) receptacle, sepals (calyx), petals (corolla) - perianth
               stamens - anther, filament (androecium)
           (3) pistil - stigma, style, ovary contains ovules composed 
               of carpels, (gynoecium)
           (4) ovules - funiculus, placenta, axile placentation
       b - discription of flower parts
           (1) complete - incomplete
           (2) perfect - imperfect
           (3) fusion - adnation
           (4) ovary - superior (hypogynous)
       c - life cycle
           (1) male - tapetum
               microsporocyte - meiosis
               mitosis - tube cell
               generative cell - forms 2 sperm
               pollen - architecture, sporopollenin
           (2) female - nucellus
               megasporocyte - meiosis, 3 abort and 1 survives
           (3) embryo sac - 3 mitotic divisions; forms 3 antipodals,
               egg, 2 polar nuclei, 2 synergids
       d - pollination - vectors (wind, insects), stigma receptive,
           pollen tube
       e - fertilization - double forms zygote, primary endosperm nucleus
       f - seed (from ovule) - seed coat (integuments), stored food -          
           cotyledons, endosperm, perisperm, embryo - development
           (1) zygote divides to form suspensor and proembryo - then
               globular - heart-shaped, torpedo, mature embryo
               Embryo potential - apomyxis, somatic embryogenesis
   9 - Mature dicot seed - epicotyl, hypocotyl, plummule, radicle
       Seed coat - hilum, micropyle
       Monocot seed - scutellum
       Coleoptile, coleorhiza, endosperm
   10 - Dissemination of seeds
       (1) assisted by fruit (dry or fleshy)
       (2) fruit layers (ovary wall) - exocarp, mesocarp, endocarp
   11 - Seed germination
       (1) dormancy - temperature (cold, fire)
       (2) immature embryo, impermeable seed coat, chemical materials
       (3) process - hydration, water uptake
   12 - Seedling development
       (1) radicle - root
       (2) hypogeous, epigeous
       (3) plummule - shoot system

 

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