Transcript Botany Unit Notes - Mr. Tate's Biology Site

Botany Unit Notes
Part II
Seed Producing Plants
Plants require water to
photosynthesize sugars and make
food
 Many plants even need water for
reproduction!
 The evolution of seed plants did
away with the need for water in
reproduction
 This was one reason leading to the
success of seed plants on Earth

Seed Producing Plants

Seed plants form male and
female gametes
Sperm are the male gametes and
they are in the form of pollen
 The female gamete is an egg
 Pollination is when a pollen
grain fuses with the egg cell of
the female plant/organ

Advantages for Seeds

Seeds nourish and protect plant embryos


Under the right conditions a seed will germinate
(next slide)
Seeds allow plants to be dispersed other
places

Seeds can pass through the digestive system of
most animals without being damaged
Seed Germination
Types of Seed Plants

There are Two types of Seed
Plants:

Gymnosperms are seed plants that
do not produce fruits
 Most
have cones as reproductive organs
like pine trees and cycads
 Gymnosperm means “naked seed”

Angiosperms are the flowering plants
that do produce fruits and have
flowers as reproductive organs
 “enclosed
seed”
Gymnosperms

Gymnosperms make up 3 distinct groups:
Gnetophytes – phylum Gnetophyta makes up
about 70 species today and are considered
“living fossils”
 Cycads – phylum Cycadophyta are palm-like
plants that reproduce using large cones and
appeared around 225 mya!
 Conifers – phylum Coniferophyta are the
traditional “pine trees” making up the majority
of Gymnosperms with 500 species

Conifer Life Cycle
Angiosperms

Angiosperms are also called
flowering plants
They have flowers as their
reproductive organs
 Angiosperms produce many
different kinds of fruits

Fruits are considered the wall of
tissue surrounding the seed
 Fruits come in many forms like
an apple or a dandelion

Angiosperms
Angiosperms owe their
success to their ability
to attract pollinators
and seed dispersers
 Animals that eat the
fruits can pass the
seed through their
digestive tracts and
deposit the seed far
away from the original
plant!

The Flower
Flowers have male
and female organs
 Ovule = egg
 Pollen = sperm
 Pollen “stick” to
the top of the
stigma and travel
down the style to
the ovary
(pollination)

Angiosperm Life Cycle
Angiosperm Diversity
Angiosperms are the most diverse plant
group on the planet with over 230,000
species!
 We can categorize Angiosperms based
on three traits:

Monocots & Dicots (aka. Eudicots)
 Woody & Herbaceous
 Annuals, Biennials, and Perennials

Monocot vs. Dicot
Monocot vs. Dicot
Monocots have fibrous roots while
 Dicots have taproots

Woody vs. Herbaceous
A plant’s stem is an
identifying characteristic
 It can be herbaceous
when it is soft and easily
cut with sheers
 It can also be woody
and be rough to the
touch like the bark of a
tree

Plant Lifespan




Plants can live anywhere from one year
to several years
Annuals – are plants that mature from
seeds, produce flowers & fruit, and die
all in one year
Biennials – are plants that take two
years to complete their life cycle storing
some of their nutrients in underground
rhizomes at the end of the first year
Perennials – are any flowering plants
that live for more than two years