Plants as Living Organisms

Plants as Living OrganismsPlant and Soil ScienceThe Plant KingdomPlants are found in biomes from the tundra to the desert. Four Major Groups of plants: mosses, ferns, gymnosperm, and angiosperm.

Gymnosperm: produce plants that produce seeds on the scales of cones. Ex. Pine, spruce, fir

The Plant KingdomAngiosperm: Flowering plantsEx. Corn, wheat, apples, petunias, oak Two ClassesMonocots: send up a single cotyledonLong narrow blades, with parallel veins, flowers in multiples of three, vascular bundles are scattered

Dicots: send up two cotyledonsBroad leaves, netted veins, vascular bundles in a circle, flowers in fours or fives

The Plant Kingdom- Life CyclesLife Cycle: the time from when a plant begins growing until it dies

Annual: germinates, grows, and reproduces in one year.

Biennial: two growing seasons, first year they grow, second year they reproduce. The Plant Kingdom- Life CyclePerennial: life cycle of two or more yearsHerbaceous: soft shoots that are killed by frost. Send up new shoots in the spring

Woody: trees, shrubs, and vines above ground that survive winter

Hardy: how tolerant to cold a plant is

Structures- Roots Function:

Absorb water and minerals from soil

Anchor plant

Store food Structures- Roots Most roots found in top 2 feet of soil

Primary root (radical) is the first root put out by the plant

Root hairs are near the growing tip of the root and increase surface area for absorption. Structures- Roots Root SystemsTap RootThick main root that grows straight downCan work for storageEx. Carrots, beets, and radishes Fibrous RootBranching slender rootsLess tolerant of dry conditionsHold soil in place, and prevents erosion Structures- Roots

Structures- Roots Secondary roots: branch off the primary root

Root cap: tip of root, protects root from soil as the root grows Structures- Stems Function:Hold leaves upright

Conduct water and minerals

Conduct food

Store food

Structures- Stems Conducting food and waterTwo types of conductive tissue- Xylem and Phloem

XylemTransports water from the roots up to the leaves

PhloemTransports food to the roots and other parts of the plant

Structures- Stems/ BudsBuds- contain undeveloped leaves, stems, or flowers. Bud scales protect the bud.

Terminal bud: large tip of the twig, the growing tip, contains the apical meristemApical meristem is the primary growing point

Lateral buds are located along the sides of the branch

Structures- Modified Stems Some stems have been modified for food storage and underground growth

Bulbs, corms, rhizomes, and tubers are all examples of modified stems

Structures- Modified Stems Bulbs- tulips and onions, have scales

Structures- Modified Stems Corms- Gladiolus and crocus, fleshy and scale covered

Structures- Modified Stems Rhizomes- underground stem that produces branches, irises and lily of the valley

Structures- Modified Stems Tubers- storage organs, potatoes and caladium

Structures-LeavesResponsible for food productionPhotosynthesisTranspiration

Structure-LeavesComprised of specialized cellsEpidermis-protective layers

Cuticle-waxy coating

Stomata-pores allowing O2, CO2, and H2O exchange

Guard cells-controls stomata

(xylem and phloem)Structure-LeavesPhotosynthetic tissuesMesophyll- Middle of the leaveBulk of PhotosynthesisPalisade layerSpongy layer

Structure-LeavesSimple leavesSingle leaf blade and petioleCompoundPetiole, 2 or more leaves called leafletsBroadleaf Plants- wide flat leaves

Structure-LeavesDeciduousLooses leave in FallEvergreenKeep leaves year roundNarrow leaf plants- needle or scale shape leaves

Structures- Flowers

Structures- FlowerFemale- Pistil Stigma- Top sticky portion to catch the pollen

Style-Tube that carries the pollen to the ovary

Ovaries-Where the seed will develop

Structures- FlowerMale- Stamen

Anther- Holds pollen

Filament- Holds the anther

Pollen- Male gamete Complete VS. IncompleteComplete Flower-Male and female flower on one flower. Able to Self Fertilize Incomplete Flower-Male OR Female Flower. Must have both to pollinateCan be on the same plant or on different gender plants.