11.4 Angiosperms
Many Plants are Flowering &
Fruiting Plants
11.4 Angiosperms
have flowers & fruit
 An angiosperms: Plants w/flowers &
fruits.
 Examples: Peanuts, grapes, squash,
roses, spider plants, grasses
 Most plant species alive now are
angiosperms.
 Sperm of flowering plant = pollen grain
 Do not need an outside source of water
to reach the eggs.
11.4
Angiosperms
 Difference between Angiosperms &
Gymnosperms:
 Sperm and egg cells are contained in the
flower in an angiosperm
 Flower is the reproductive structure of an
angiosperm
 Eggs cells develop in an ovary
 After fertilization of egg, ovary wall thickens,
& ovary becomes the fruit
11.4 Angiosperms
 Embryos are enclosed within seeds.
 Both Gen1 Gen2 occur within a single
plant.
 Both Angiosperms and Gymnosperms
have separate male & female
reproductive structures.
 Some species have separate male and
female plants
11.4 Angiosperm Life
Cycle
 Flower is reproductive
structure
 Stage 1
 Meiosis in Anther (male part) produces sperm cell
inside the pollen grains
 Meiosis in ovary of the Pistil (female part) produces
the egg
 Stage 2
 Pollen released; catches on pistil which has a
mature egg cell in the ovary
11.4 Life Cycle cont.
 Stage 3
 Fertilization occurs when the pollen tube
reaches the ovary & sperm fertilizes the egg
 Fertilized egg grows into an embryo and
develops a seed coat.
 Ovary develops into a fruit
 Stage 4
 Fruit falls to ground; germinates into new
plant
11-4 Flowers
 Vary in size, shape, color, fragrance
 Some have reproductive structures (both)
in 1 flower.
 Some have male reproductive structures
in 1 flower; female in another
 Sepals = leafy structures that enclose the
flower. They open, fall off after blooming.
11.4 Flowers
 Petals are leafy structures arranged in a
circle around the pistil. Petals open as
reproductive structures mature.
 Petals=most colorful part of flower & may
attract animal pollinators (butterlies;bees)
 Stamen = male reproductive structure of
a flower. It includes: filament stalk &
anther. Anther produces pollen
11.4 Flowers
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Pistil = female reproductive structure
Ovary - Located at the base of the pistil
Contains egg cells that mature into eggs
Stigma = top of pistil where pollen grains
attach.
11.4 Fruit
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Fruit = ripened plant ovary.
Some ovaries contain 1 seed (Avacado)
Some contain many (apple)
“Fleshy” fruits because they have juicy
flesh = cherry, apple, corn
 Dry fruits (peanuts, walnuts, sunflowers)
 Some seed coats have “wings” to help
them spread.
How seeds spread
 Interactions between plants and
animals
 Food source
 Animals spread seeds (eat;
carried on fur)
 Animals spread pollen
 Example: Bees & spread pollen &
make honey;
11.4 Humans need plants
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For food (fruit/veggies) and O2
For Energy Resources (natural gas or coal)
and Soil for growing crops
Other Products
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Building homes
Making paper
Cotton for jeans/clothes
Dyes for fabric
Medicines like Aspirin