KINGDOM: PLANTAE

Chapter 20-25

Vocabulary

• Adaptation• Alternation of

generations• Colonial• Dicots• Enclosed seeds• Flowers• fruit

• Leaves• Monocots• Multicellular• Pollen• Roots• Seeds• Stems• Unicellular• Vascular tissue

Green Algae, Moss, and Ferns

• Describe characteristics – p. 433-438, 448-452, 455-457

• Benefits of alternation of generations – p. 440-441, 451-454, 458-459

• Unicellular, colonial, multicellular algae diversity – p. 435-438

• Ecological roles – p. 442, 460-461• Moss as pioneers – p. 449-453• Adapting to land – p. 452-453, 455-456

Gymnosperms

• Characteristics – p. 467-473• Adapting to land with respect to: alternation

of generations, needles, seeds, pollen, vascular tissue – p.469-470, 473, 492-493, 534

• Role of meristems in primary and secondary growth – p. 491

• Economic and ecological importance – Chapter 49. p. 1063-1065

ANGIOSPERMS

• Characteristics – p. 473-476, 517-518, 534-539

• Compare and contrast gymnosperms and angiosperms relating to adapting to land – p. 467-470, 473-474, 476-481, 508-511

• Monocots and dicots – p.474-475, 539-540

Characteristics of Plants1. multicellular2. eukaryotic-- have a nucleus-- DNA inside nucleus (in the form of

chromosomes)3. have cell wall with cellulose4. aerobic5. autotrophic (photosynthesize - have

chlorophyll)6. large (compared to bacteria)

Plant Evolution

Reproduction in Plants

• Sexual reproduction: go through 2 different life stages using a method called “alternation of generations

• Asexual reproduction: by fission, fragmentation or zoospores (motile spores)

Alternation of GenerationsA life cycle in which there are two distinct life stages

that occur alternately for a species

Stage 1 • Diploid (2N – each cell has two sets of chromosomes)

– Called the sporophyte– Produce gametes (= sex cells = haploid cells) by meiosis

Stage 2• Haploid (1N – each cell has one set of chromosomes)

– Called the gametophyte– Fuse to form a sporophyte (= zygote = diploid cells) by

fertilization

Evolutionary Trends in alternation of generations

• Note that as plants have evolved into more complex, larger forms– The diploid stage is

larger relative to the haploid stage

– The diploid stage is the longer lasting stage in the life cycle

Adaptation to life in waterNo problem with:1. dehydration2. rapid temperature changes3. extreme temperatures (narrower temp.

range in the oceans)4. support

Adaptation to life on land1. keep membranes moist for gas exchange (e.g.,

roots in the soil)2. support without buoyancy of water (e.g., woody

stem)3. transport water in the body (e.g., vascular

system)4. conserve water in the body (e.g., leathery

tissues)5. reproduction in a dry environment (e.g.,

pollination)6. development of the early embryo (e.g., in a

protective seed)7. survive rapid environmental changes (e.g.,

dormant)