Flowerin g Plants Chapter 25 Notes
Dec 15, 2015
Angiosperms
• Phylum Anthophyta• Anthus “flower” phyt “plant”• 300,000+ species• Earth’s Dominant Plants
Flowering Plants
• Like gymnosperms:– Flowering plants have vascular tissues
and produce seeds – Heterosporous – megaspores and
microspores
• Unlike gymnosperms:–Ovules of flowering plants are enclosed
within an ovary
KEY TERMS
• OVULE – Structure in the ovary that contains a
female gametophyte and develops into a seed after fertilization
• OVARY – Base of a carpel or fused carpels that
contains ovules and develops into a fruit after fertilization
Flower Parts
Female Parts
The Pistil – 1+ Carpels• Stigma - sticky• Style – the neck
connecting stigma to ovary
• Ovary – houses ovules (each contains 1 egg)
Male Parts
The Stamen• Anther – produces
pollen grains• Filament - stalk
Ecology and Economy
• Our survival as a species depends on flowering plants –Major food crops
• Products – Cork, rubber, tobacco, coffee, chocolate,
aromatic oils for perfumes – Valuable lumber– Fibers and medicines– Clothing
Economic Botany
• Subdiscipline of botany that deals with plants of economic importance–Most of these are flowering plants
KEY TERMS
• COTYLEDON – The seed leaf of a plant embryo, which
may contain food stored for germination
KEY TERMS• MONOCOT – Seeds contain a
single cotyledon
–Monocots have floral parts in threes
–Monocots include grasses, orchids, irises, onions, lilies, palms• Mostly Herbaceous
KEY TERMS• EUDICOT – Seeds contain two
cotyledons
– Eudicots have floral parts in fours or fives
– Eudicots include oaks, roses, mustards, cacti, blueberries, sunflowers
Life Cycle
• Flowering plants undergo an alternation of generations:– Sporophyte generation is larger and
nutritionally independent– Gametophyte generation is reduced to
only a few microscopic cells
KEY TERMS
• DOUBLE FERTILIZATION – A process in the flowering plant life
cycle in which there are two fertilizations
– One results in formation of a zygote
– Second results in formation of endosperm
KEY TERMS
• ENDOSPERM – The 3n nutritive tissue formed at
some point in the development of all angiosperm seeds
– Formed by double fertilization• The two polar nuclei fuse with the second
sperm cell
Adaptations of Flowering Plants
• Reproduce sexually by forming flowers• Form seeds within fruits after double
fertilization• Efficient water-conducting vessel
elements in xylem • Efficient carbohydrate-conducting
sieve-tube elements in phloem• Have pollen grains transported by wind,
water, insects, other animals
KEY TERMS
• APOMIXIS – A type of reproduction
– Fruits and seeds are formed asexually
– No fusion of gametes
– Embryo is genetically similar to parent
– Plants that reproduce by apomixis: dandelions, citrus trees, blackberries, garlic, certain grasses.
KEY TERMS
• BASAL ANGIOSPERM – Group of angiosperms thought to be
ancestral to all other flowering plants
• CORE ANGIOSPERM – Group including most angiosperm species
– Divided into three subgroups: magnoliids, monocots, and eudicots
KEY TERMS
• MAGNOLIID – One of the groups of flowering plants
– Core angiosperms once classified as “dicots,” but molecular evidence indicates they are neither eudicots nor monocots
– Includes species in magnolia, laurel, and black pepper families, several related families
Flowering Plant Families 1
• More than 300 families
• Magnolia family– Important ornamentals and source of
timber– Examples: southern magnolia, tuliptree
Flowering Plant Families 2
• Walnut family– Provides nuts for food, wood for furniture – Examples: English walnut, black walnut,
pecan
• Cactus family – Important as ornamentals– Examples: prickly pear, Christmas cactus
Flowering Plant Families 3• Mustard family–Many important food crops– Examples: cabbage, broccoli, cauliflower,
turnip, mustard
• Rose family– Commercially important fruits and
ornamentals– Examples: apple, pear, plum, cherry,
apricot, peach, strawberry, raspberry, rose
Flowering Plant Families 4
• Pea family– Important food crops– Examples: garden pea, chick pea, green
bean, soybean, lima bean, peanut, red clover, alfalfa
Flowering Plant Families 5
• Potato family– Important food crops and chemicals used
as drugs– Examples: potato, tomato, green pepper,
eggplant, petunia, deadly nightshade (belladonna)
Flowering Plant Families 6
• Pumpkin family– Food crops– Examples: pumpkins, melons, squashes,
cucumbers, cantaloupe, honeydew, muskmelon, cucumber, watermelon
Flowering Plant Families 7
• Sunflower family– One of the largest families of flowering
plants– Examples: chrysanthemums, marigolds,
sunflowers, daisies, and some food plants such as lettuce, globe artichokes
Flowering Plant Families 8
• Grass family–Most important family of flowering
plants from the human standpoint– Examples: rice, wheat, corn, oats,
barley, rye, sugarcane, bamboo
Flowering Plant Families 9
• Orchid family– One of the largest families of flowering
plants; contains a greater variety of flowers than any other family
– Example: the vanilla orchid
• Agave family– Best known for ornamentals– Examples: century plant, sisal hemp,
bowstring hemp