Plant Kingdom Mrs. Wetzel Biology
Feb 25, 2016
Plant KingdomMrs. Wetzel
Biology
What is a plant• Eukaryotic• Multicellular• Mostly Autotrophs• Cell walls made of cellulose
In order to survive• All plants Need:
– Sunlight– Water– Gas exchange– Movement of water and nutrients
Evolution• Most plants started out in the
water• They were able to survive on land
because of– Adaptations to retain moisture
– Cuticle– Seeds
Plant classification• Botanists divide plants into four
groups based on three features:– 1. Vascular tissue– 2. Seeds– 3. Flowers
Plant Kingdom:• Bryophytes= mosses & their
relatives• Vascular Non seed= Ferns & their
relatives• Gymnosperms• Angiosperms
Plant Diversity• Bryophytes- mosses, liverworts,
hornworts– Need water for their reproductive
cycle– Do not have vascular tissue=
must remain short rely on osmosis
Bryophytes: mosses/liverworts/hornworts
Bryophytes: Ecology• Peat Moss- used in gardening,
improves the soils ability to retain water
Biodiversity/ Symbiosis
Plant Kingdom:• Bryophytes- Mosses• Non- Seed Vascular – ferns• Gymnosperms- cone bearing• Angiosperms- seed bearing
Non-Seed Vascular PlantsAKA Spore Plants
• These are the first plants that have adapted to have specialized tissues used to conduct water. This is called vascular tissue
Non-Seed Vascular PlantsAKA Spore Plants
• Vascular tissue is a type of tissue specialized to conduct water- this was a very important adaptation to allow plants to live on land– What are the two types of vascular
tissue?
Non- seed Vascular• Vascular tissue is a type of tissue
specialized to conduct water- this was a very important adaptation to allow plants to live on land– What are the two types of vascular
tissue?– Xylem, Phloem
Non-Seed Vascular Plants• Ferns, Club Mosses, Horsetails
Non-Seed Vascular PlantsAKA Spore Plants
• Non-seed vascular plants reproduce using spores which are found on the underside of their fronds.
• Fronds is what botanists call the leaves of ferns
Seed Plants • The two groups of seed plants are
the:– Gymnosperms – Angiosperms
Seed Plant adaptations• Seed plants have adapted to life
outside of water by:– Reproducing with flowers or cones– Pollination– Protecting embryos in a seed
Gymnosperms• Cone Bearing Plants
– Gnetophytes Gnetophyta– Cycads= Cycadophyta– Ginkgoes= Ginkgoephyta– Coniferophyta = Conifers
Conifer Ecology• Conifers thrive in habitats with
limited water because of several adaptations including long thin leaves (needles) coated with a hard waxy cuticle.
• Leaves do not fall in the winter. Older needles are gradually replaced by new ones (evergreen)
Name some plants:
Angiosperms• Almost 90% of living plants are
angiosperms• Angiosperm means “enclosed
seed”
Angiosperms• The fruit is a thick wall of tissue
surrounding the seed. The fruit is what has made angiosperms so successful.
• By using fruit to attract animals the angiosperms ensure the seeds will be dispersed
Angiosperms• There are two types of
angiosperms:– Monocots– Dicots
Angiosperms• Monocots-
– Single seeds– Parallel leaf veins– Floral parts in multiples of three– Fibrous roots
Monocot leaf
Angiosperms• Dicots
– Two cotyledons– Leaf veins are branched– Floral parts are in multiples of 4 or 5– taproots
Dicot Leaves
Seed Distribution• Seeds are distributed in plants just
like spores are in fungi– Wind– Animals
Life Spans • Annuals- complete their entire life
cycle in one year• Biennial= two years, flowering
occurs during the second year• Perennials= many years
Annuals
Perennials
Perennial• Buffalo grass of the north
American Plains has been growing since the end of the last ice age, or 10,000 years
Structure and Function• Structure & function: What
physical characteristics does something have? How do these physical characteristics influence it’s “job”
Structure & Functionin plants
Three main parts of plants1. Roots2. Stems3. Leaves
Structure & Function• Roots
– The job of a root is to anchor the plant to the soil, absorb minerals, conduct water and nutrients, and store food
Fibrous / Tap
Structure & Function • Tap Root- Many dicots have a
taproot system consisting of one large vertical root that produces tiny hair like horizontal roots.
Structure & Function• Fibrous Roots- Monocots including
grasses have fibrous roots which spread out like a mat just below the soil surface.
Structure & Function• Both types of roots are designed to
anchor the plant. Both do so in different ways
• A similarity of both root systems is that they absorb most of the water through root hairs.
• Roots hairs increase surface area
Structure & Function • Stems- A stem has an alternation
of NODES- that point at which leaves are attached, and internodes- the stem segments between the nodes.
Xylem / Phloem
Plant Tissue
Multicellular VS. Unicellualrthe thing that distinguishes multicellular organisms from unicellular organisms is cell specialization. Plants have cells that are specialized for transporting nutrients.
Structure & Function • Veins
– Each vein in a plant has two types of tissue;• Xylem- transport water and dissolved
minerals upward from the roots• Phloem- transports food made in the
leaves to non-photosynthetic parts of the shoot system
Plant Cells• Tracheids & Vessels
– Xylem- is composed of two cell types, Trachieds & Vessels- Both cells are dead. Before they die they form rings that can stretch as the plant grows
Structure & Function• Leaves are the main
photosynthetic organs of plants.• Leaves are made up of a flattened
Blade, and a petiole which attaches the leaf to the node of the stem
Structure & Function • Monocot & Dicot
leaves differ in how their veins are arranged
• Monocots veins run parallel
• Dicot veins are netlike
* Leaf Morphology • Arrangement of leaves on a stem
can be • Opposite• Alternate • Whorled
Leaf Anatomy• The surface of the leaf is covered
in a waxy cuticle, this is to prevent water loss
Leaf anatomy• The cuticle is interrupted by guard
cells and stoma• Stomata allow gas exchange
between the air and the photosynthetic cells inside the leaf
• Stomata are also how leaves undergo transpiration
Surface of a leaf
Stomata
Guard Cells
Transport • Plants lose a great volume of water
during transpiration. An average sized maple tree looses 200L of water an hour
Transport• Pushing- Root pressure “pushes”
nutrients & water “up” the plant• Pulling- Transpiration-Cohesion-
Tension Mechanism- capillary action
Reproduction• Gymnosperms reproduce with
cones
Gymnosperm reproduction
Reproduction• Flowers are the reproductive
organs of angiosperms
Seed dispersal• Seed are dispersed though wind,
water, and animals.
Plant Hormones• Plant hormones are chemical
substances that control a plants patterns of growth and development, and the plants responses to environmental conditions
Plant Hormones• Auxins- control phototropism
Phototropism is the tendency for a plant to move toward a source of light
Phototropism
Plant hormones• Auxins also control gravitropism
• Gravitropism is the tendency of a plant to grow in a direction in response to the force of gravity
Gravitropism
Plant Hormones• Cytokinins- stimulate cell division
and cause dormant seeds to sprout
Plant hormones• Gibberellins- produce a dramatic
increase in size, particularly in stems and fruit
Tropisms• Thigmotropism- a plants response
to touch (vines wrapping around things)
Photoperiodism• Photoperiodism in plants is
responsible for the timing of seasonal activities such as flowering and growth