Chp 21-22

Question 0

How do Plants Affect other Organisms?

Answer 0

Plants play a crucial Ecological Role; Provide Humans with necessities and luxuries.

Question 1

What Are The Key Features of Plants?

Answer 1

Plants have multicellular, Dependent Embryos; Plants have Alternating Multicellular Haploid and Diploid Generations

Question 2

What is the Evolutionary Origin of Plants?

Answer 2

The Ancestors of Plants were aquatic.

Question 3

How do Plants adapted to Life on Land?

Answer 3

Plant bodies resist gravity and drying; Plant Embryos are protected, and some plats have sex Cells that disperse without water.

Question 4

What are the Major groups of Plants?

Answer 4

Nonvascular Plants Lack conducting structures; Vascular plants have conducting cells that also provide support; The seedless vascular plants include the Club Mosses, Horsetails, and Ferns;
The Seed Plants are Aided by two important adaptations: Pollen and seeds; Gymnosperms are nonflowering Seed Plants and Angiosperms are Flowering Seed Plants; Recently evolved plants have smaller gametophytes.

Question 5

What is photosynthesis ?

Answer 5

The process by which plants use energy from sunlight to convert water and carbon dioxide to sugar. The color comes from the presence of the pigment chlorophyll in many plant tissues.

Question 6

What distinguishes plants from other organisms?

Answer 6

Their multicellular Embryos.

Question 7

What distinguishes plants from algae?

Answer 7

Multicellular, dependent embryos that are not found among photosynthetic protists.

Question 8

Describe Alteration of Generations

Answer 8

A life cycle, typical of plants , in which a diploid sporophyte (spore -reproducing) generation alternates with a haploid gametophyte (gamete-producing) generations. In organisms with this, separate diploid and haploid generations alternate with one another. (Diploid has two sets of chromosomes; a haploid one)

Question 9

What is a Sporophyte

Answer 9

In the diploid Generations, the body consists of diploid cells (sporophytes) In plats the multicellular embryos described are part of the diploid sporophyte generation) The multicellular diploid stage in the life cycle of a plant; produces haploid, asexual spores through meiosis.

Question 10

What is Gametophytes

Answer 10

The multicellular haploid stage in the life cycle of a plant. Certain cells of sporophytes undergo meiosis to produce haploid reproductive cells called spores and they develop into gametophytes.

Question 11

Alternation of Generations in plants : Plant life cycle

Answer 11

A Diploid sporophyte generation produces haploid spores through meiotic cell division -> the spores then develop into a haploid gametophyte generation that produces haploid gametes by mitotic cell division -> the fusion of these gametes results in a diploid zygote that develops into the sporophyte plant.

Question 12

How do plants help the ecosystem?

Answer 12

Capture energy that other organisms use, help maintain atmosphere with oxygen gas as a by-product of photosynthesis; Plants build soil when they die its stems, leaves, and roots become food for fungi, prokaryotes and other decomposers. Making soil more fertile. Keep Earth Moist.

Question 13

How do plants provide us with Necessities and Luxuries?

Answer 13

Nothing for humans would’ve been possible without plants. Plants provide shelter, fuel and medicine. Wood is fuel. Coal is composed of remains of ancient plants that have been transformed by geological process; Drugs such as aspirin, heart medicine, cancer treatments Taxol and vinblastine, the malaria drug quinine, the painkillers codeine and Morphine, and more.

Question 14

What is the evolutionary origin of plants?

Answer 14

Ancestors are photosynthetic protists similar to the modern algae known as stoneworts. They are plants closest to living relatives; DNA comparisons show evolutionary relationship; Green algae and plants use the same type of chlorophyll and accessory pigments in photosynthesis.

Question 15

Ancestors were aquatic

Answer 15

Modern stoneworts , the protists that gave rise to plants lacked roots, stems, leaves and complex reproductive structures such as flowers or cones, features that appeared only later in the evolutionary history of plants. ; Life in water had many advantages; Water a body is bathed in a nutrient-rich solution, and supported by buoyancy and not likely to dry out. Life in water facilitates reproduction, because gametes (sex cells) and zygotes (fertilized sex cells) can be carried by water currents or propelled by flagella.

Question 16

How did the plants adapted to live on the mainland?

Answer 16

Structures that support the body and conserve water, conducting cells that transport water and nutrients to all parts of the plant, and processes that disperse gametes and zygotes by methods that are independent of water.

Question 17

How do they resist gravity and drying?

Answer 17

Roots or root-like structures that anchor the plant and absorb water and nutrients from the soil; A waxy cuticle (fatty coating no the surfaces of aboveground epidermal cells of many land plants) that covers the surface of leaves and stems and limits the evaporation of water ;

• Porse called Stomata (sing, stoma) in the leaves and stems that open to allow gas exchange but close when water is scarce, reducing the amount of water lost to evaporation.
• Later in the transition to terrestrial life:
  - Conducting cells that transport water and minerals upward from the roots and that move photosynthetic products from the leaves to the rest of the plant body.
  
  • The stiffening substance lignin, which is a rigid polymer that impregnates the conducting cells and supports the plant body, helping the plant expose maximum surface are to sunlight.

Question 18

Plant embryos are protected how?

Answer 18

Seed plants: characterized by specially well-protected and provisioned embryos and waterless dispersal of sex cells. Key adaptation of these plants are seeds, pollen, and , in the flowering plants, flower and fruits.

Question 19

Major Groups of Plants

Answer 19

• Non vascular (bryophytes) require a moist environment to reproduce and thus straddle the boundary between aquatic and terrestrial life (like amphibians of the animal kingdom)
• Vascular (Tracheophytes) drier habitats colonizer

Question 20

How do Non vascular plants conduct nutrients.

Answer 20

• THey retain some characteristics of algae. Lack true roots, leaves and stems.
• Posses Rhizoids (rootlike anchoring structures)
• Do not have structures for conducting water and nutrients so rely on poorly developed conducting tissues.
• Body size is limited. Also limited by the absence of any stiffening agent in their bodies. (less than an inch tall).

Question 21

What is the evolutionary tree like in Plants?

Answer 21

Liveworts -> Mosses -> Ferns -> Gymnosperms and Angiosperms

Question 22

Non vascular plants

Answer 22

Hornworts, liveworts, and mosses. Named for their shapes. Features - Haploid spores are carried by wind, early embryonic development occurs within the archegonium of a gametophyte.

Question 23

Vascular Plants

Answer 23

Ferns, conifers, and flowering plants: Water and nutrient transport structures: All have different features.

Question 24

Reproductive structures of Nonvascular Plants

Answer 24

They require moisture to reproduce but they have evolved for land . Structures on land are enclosed, which prevents the gametes from drying out - There are two types of reproductive strucutures : Archegonia (Archegonium) in which eggs develop, and antheridia (antheridium) where sperm are formed. In some non vasculars, both structures are located on the same plant ; in other species, each individual plant is either male or female. Rely on Diffusion

Question 25

Vascular plants have conducting cells that also provide support

Answer 25

Tube-shaped conducting cells. Impregnated within the stiffening substance lignin and serve both supportive and conducting functions. - Grow taller, extra support provided by lignin and because the conducting cells allow water and nutrients absorbed by the roots to move to the upper portions of the plant. Divided into two groups:
Seedless Vascular and the seed Plants.

Question 26

The seedless vascular plants include

Answer 26

Club Mosses, Horsetails and Ferns.
-seedless plants have swimming sperm and require water for reproduction. THey rather propagate by spores instead of seeds.
Used to be the predominant plant in the landscape.

Question 27

Club Mosses

Answer 27

NOT A MOSSES. Limited in height. Small leaves and leaflike structures. (ground pine)

Question 28

Horsetails

Answer 28

15 species, less than 3 ft tall. Bushy branches, leaves are reduced to tiny scales , scouring rushes because they deposit large amounts of silica (glass) in their outer layer of cells.

Question 29

Liverworts

Answer 29

Liver Herb

Question 30

Hornworts (lycophyta)

Answer 30

100 species of it , damp locations

among the earliest land plants.

Question 31

Vascular:

Answer 31

Conducting cells : Ligning, Diploid sporophyte generation is dominant
2 main Groups:

Question 32

Seedless:

Answer 32

Swimming sperm require water for reproduction
Reproduce by spores
Do not produce seeds

Question 33

Ex: Ferns (pterophyta)

Answer 33

Largest most diverse group of seedless vascular (12, 000 species)

• Well developed, broad leaves emerge from coiled fiddleheads
• only seedless vascular plants that have broad leaves
• Requires moisture to reproduce.

Question 34

Resurrection Fern

Answer 34

Epiphyte: Grows branches on rocks off the ground.

Question 35

Vascular plants: Seeded

Answer 35

Pollen and seeds

- Pollen grains are tiny male gametophytes that carry sperm-producing cells.

Question 36

Gametophytes are very reduced in size and depend on the sporophyte for nutrition

Answer 36

Female gametophyte is a small group of haploid cells that produce the egg.
-male gametophyte is the pollen grain itself.
Include - Gymnosperms (lack flowers)
- Angiosperms (produce flowers)

Question 37

Gymnosperms

Answer 37

Evolved before flowering plants (angiosperms)

Question 38

4 groups of Gymnosperms :

Answer 38

1. Ginkgos
2. Cydas
3. Gnetophytes
4. Conifers.