Chapter 32 - Plant Reproduction

mitosis

cell division

meiosis

cell divides twice to produce four sex cells

calyx

the sepals of a flower that enclose the petals

corolla

ring of petals of a flower that includes the flowers reproductive organs

carpel/pistil

female reproductive parts of a flower. includes stigma, style and ovary

stamen

male reproductive parts of a flower. includes anther and filament

monoecious

both male and female flowers on the same plant (ex: walnut)

dioecious

male and female flowers on separate plants (red maple)

pollination

pollen containing the male genetic material is transferred to the female part of a flower (the stigma)

pollination syndrome

set of flower characteristics that are linked to specific pollinators

nectar guide

visual patterns on flowers that help pollinators locate nectar and pollen

cotyledon

first leaf of a plant seedling

hilum

scar or mark on a seed that marks the point of attachment to its seed vessel

vernalization

plants are induced to flowering process by exposure to cold temperature

scarification

process of breaking down a seeds hard outer coat to encourage germination

cutting

a piece of a plant that can be used to make a new independent plant

grafting

two or more plants are joined together so they grow as a single plant

senescence

natural process of aging in plants

five examples of asexual reproduction for plants

rhizomes, stolons, bulbs, corms, tubers

vegetative propagation

cuttings and graftings

sexual reproduction

two types of seed plants

angiosperms

flowering plants, seeds enclosed in carpel/fruit, broad leaves, double fertilization, pollination by animals more common

gymnosperms

• naked seeds in cones with male and female gametophytes on separate male/female cones

• difficult for self pollination

• wind pollination more common

• no fruits

• needle like or scale like leaves

examples of angiosperms

grasses, flowers, herbs, shrubs, and most deciduous trees

female gametophyte

enclosed in ovule of ovary (part of pistil)

male gametophyte

pollen grains in anther (part of stamen)

complete flower

sepals, petals, pistils, stamens

double fertilization

one sperm cell fuses with the egg to form the embryo. the other fuses with the nuclei and forms the endosperm

female cone

higher on tree

male cone

lower on tree

pollination

pollen from anther to the stigma. pollen develops into tube cell and sperm cell

self pollination

• same plant, quick

• less genetic diversity

• does not require nectar and pollen for pollinators

• reliable, no pollinators needed

cross pollination

• different plants, need pollinators

• more genetic diversity

preventing self pollination

• pollination and ovary mature at different times

• different lengths of filament and style

• location of male and female parts on the same plant

• male and female parts on different plants

• self incompatibility

mechanisms of cross pollination

wind, water, insects, birds, bats, manual/human aided

factors affecting germination time

moisture and temperature, seed size, depth in soil, light requirement

fruits main goal

seed dispersal

methods of seed dispersal

wind, water, animals, mechanical

types of fruit

simple, aggregate, accessory, multiple

simple fruits

single carpel or fused carpels of single ovary (ex: pears, watermelon)

aggregate fruits

more than one carpel (ex: raspberry blossom)

multiple fruit

cluster of flowers fuse to form fruit (ex: pineapple blossom)

accessory fruit

not from the ovary (ex: apple)

fruit

seed bearing structure that develops from the ovary

vegetable

edible leaves, stems or roots of a plant

asexual reproduction

involves one parent, no gametes, genetically identical offspring

sexual reproduction

involves two parents, fusion of male and female gametes, genetically varied offspring

staminate flower

has stamens only (male)

carpellate flower

has carpels only (female)

three female structures of the carpel

stigma, style and ovary

stigma

receives pollen

style

connects stigma to ovary

ovary

contains ovules

anther

produces pollen

filament

supports the anther

two male structures of the stamen

anther and filament

complete flower

has all four whorls (sepals, petals, stamens, carpels)

incomplete flower

missing one or more whorls

reproduction in corn

• tassels - male flowers that produce pollen

• silks - female structures, each silk is attached to an ovule

• wind pollinates corn, pollen from tassels lands on silks

egg cell

located at the bottom of the embryo sac

central cell with polar nuclei

in the center, becomes endosperm after fertilization

tube cell

forms pollen tube

generative cell

divides to form two sperm cells

endosperm formation and purpose

• formed when one sperm fertilizes the central cell (double fertilization)

• nourishes the developing embryo

plumule

becomes shoot

hypocotyl

stem region below cotyledons

radicle

becomes root

endosperm

food reserve

cotyledon

stores/transfers nutrients

corpse flower

pollinated by carrion flies

skunk cabbage

pollinated by beetles and flies

giant water lily

pollinated by beetles

seed germination factors

water availability, temperature, light exposure, oxygen availability

importance of seed dormancy

allows survival during unfavorable conditions, ensure germination at optimal time