PLANTS

3. Cell walls of cellulose 4. Carry out photosynthesis What is a Plant? 1. Multicellular 2. Eukaryotic 3. Cell walls of cellulose 4. Carry out photosynthesis 5. Store energy as starch 6. Autotrophic

To prevent water loss, many plants have– ADAPTATIONS TO SURVIVE ON LAND To prevent water loss, many plants have– A. Waxy cuticle – thick layer for protection B. Stomata – Open during day; close at night; regulated by guard cells

2. Leaves are specialized for photosynthesis *Shape to trap light energy *Gas exchange occurs here Organ of photosynthesis is the leaf! What is the organelle?

3. Specialized roots for absorption of water and minerals

4. Specialized stem for transporting materials

5. Reproduction on lands needs to occur with little or no water ****MANY PLANTS PRODUCE SPORES ****AND SOME PRODUCE SEEDS

Evolution of Plants moss cone-bearing algae fern flowering Using the following words, put them in order of how you think they evolved…. moss cone-bearing algae fern flowering

EVOLUTIONARY PERSPECTIVE OF DEVELOPMENT OF PLANT TYPES: ALGAE  MOSSES  FERNS  CONE-BEARING  FLOWERING

TWO MAIN CATEGORIES OF PLANTS : 1. NONVASCULAR 2. VASCULAR

Examples of Nonvascular Plants - LIVERWORTS MOSSES

No vascular tissue! Water moves by osmosis Low-growing

2. VASCULAR PLANTS

Include 3 Main Groups: A. Ferns (Seedless) B. Gymnosperms (Seeds in cones) C.Angiosperms (Seeds in flowers)

A. XYLEM - Cells in tubes that transport water and minerals

B. PHLOEM - Tubes that transport food

Sugars Actively transported; water also moves (By osmosis) through the phloem from the SOURCE to the (Place that stores or uses sugars) SINK **PRESSURE FLOW HYPOTHESIS

Phloem Transport Phloem Xylem Sugar molecules Source cell Movement of water Movement of sugar Sink cell

Vascular Plants Include 3 Main Groups: A. Ferns (Seedless) B. Gymnosperms (Seeds in cones) C.Angiosperms (Seeds in fruits, Produce flowers)

Ferns – Seedless Vascular plants Require water for sperm to swim to egg Leaves called fronds

B. Gymnosperms Vascular plants Produce seeds on scales called cones “Naked seeds” ***Water not needed for reproduction

Carried to female cone by wind, water, insects, ... (Pollination) Pollen grain contains gametophyte and sperm! Carried to female cone by wind, water, insects, ... (Pollination) ****Pollen grows tube to join egg (fertilization) forming seed

Life cycle of gymnosperm

Most produce seeds in woody cones

Female (seed) and Male (pollen) cones

The Structure of a Seed Seed coat Seed Embryo Wing B Stored food supply Seed Wing B A

AFTER FERTILIZATION Zygote becomes an EMBRYO (Diploid sporophyte) COTYLEDONS – Seed leaf of embryo SEED COAT – Protects embryo

Advantages of Seeds *Food supply for growing plant *Protection by seed coat *Provides less competition with “parents” *Water not needed for fertilization

Largest Group of Gymnosperms are the Conifers Needle – Like leaves help retain water Flexible branches and needles so they don’t break with the weight of snow!

A few are DECIDUOUS (Lose their leaves at same time) so are dormant in winter Most are EVERGREEN so can carry on photosynthesis as soon as spring arrives

Are these xylem or phloem??? Grow tall because of wood tubes (tracheids) that support water and dissolved minerals Are these xylem or phloem??? **Bark reduces water loss

C. FLOWERING PLANTS

WHAT ARE ANGIOSPERMS? VASCULAR PLANTS PRODUCE FLOWERS DEVELOP SEEDS IN FRUITS WHICH HELPS PROTECT EMBRYO

TWO CLASSES OF ANGIOSPERMS: 1. Monocots One seed leaf in embryo Includes grasses, orchids, lilies, palms Parallel veins in leaves Flower parts in multiples of three

2. Dicots Two seed leaves in embryo Most flowering plants Leaves with netted veins Flower parts in multiples of four or five

Monocot vs. Dicot Monocot Dicot Cotyledons (seed leaves) Mono=1 Di=2 Leaf Veins Parallel Branched Flower Parts (#petals, stamen, carpels, etc) Always in multiples of 3 (ex. 3, 6, 9) In multiples of 4s and 5s Roots fibrous Tap root

Monocot or Dicot????

Monocot or Dicot?

Monocots vs. Dicots

GENERAL VASCULAR ORGAN TERMS

ROOTS STEMS LEAVES VEINS Absorption Support; transport Photosynthesis Contain xylem and phloem

1. Roots Two types of root systems: A. TAPROOT SYSTEM – Large central roots, Ex: Carrot! (most dicots)

B. FIBROUS ROOT SYSTEM – Highly branched (Most monocots)

ROOT HAIRS increase surface area for absorption ROOT CAP - Covers tip of the root and protects it MERISTEM – Growth area just behind the root tip ~Was this primary or secondary growth?

Cross Section of Plant Root (magnification: 40x) Structure of a Root Epidermis Root hairs Phloem Xylem Apical meristem Root cap Zone of maturation Zone of elongation Endodermis Ground tissue (cortex) Vascular Cylinder Ground tissue (cortex) Epidermis Endodermis Vascular cylinder Cross Section of Plant Root (magnification: 40x)

2. STEMS Two kinds – A. HERBACEOUS – Flexible vascular bundles scattered

B. WOODY – Rigid Have growth rings of vascular tissue that determine age

Layers of a Tree Trunk Wood Bark Cork Contains old, nonfunctioning xylem that helps support the tree Contains active xylem that transports water and minerals Produces new xylem and phloem, which increase the width of the stem Transports sugars produced by photosynthesis Produces protective layer of cork Contains old, nonfunctioning phloem that protects the tree Xylem: Heartwood Cork Cambium Phloem Vascular Cambium Xylem: Sapwood

3. LEAVES A. SIMPLE – One leaf blade attached to stem B. COMPOUND – Divided leaf blade attached to stem PETIOLE – stalk that attaches leaf to stem

Cross Section of a Typical Leaf MESOPHYLL – Ground tissue full of chloroplasts XYLEM PHLOEM GUARD CELL STOMA

Epidermis Cuticle Guard cell Stomata

Structure of a leaf: STOMATA

REPRODUCTION IN FLOWERING PLANTS

Structure of a Flower 1. SEPALS – Leaflike; green; arranged in circle beneath the petals *Protects the ovary! *Protects the Flower while Developing!

2. PETALS – Leaf-like and colorful to attract insects!

3. STAMEN – MALE! Male part made of ANTHER and FILAMENT Anther: produces pollen (sperm!) Filament: stalk that supports the anther

4. PISTIL/CARPEL – FEMALE! Female part made of sticky STIGMA (where pollen grains land), STYLE (transports sperm to egg), and OVARY which contains OVULES with eggs inside

Lacks one or more organs COMPLETE FLOWER – Has all four organs INCOMPLETE FLOWER – Lacks one or more organs What is this picture missing?

The Structure of a Flower Filament Anther Stigma Style Ovary Carpel Petal Sepal Ovule Stamen Is this complete or incomplete?

Transfer of pollen from the POLLINATION – Transfer of pollen from the stamen to the pistil

Adaptations for Pollination that Attract Particular Animals: 1. Nectar 2. Petal Color 3. Scent

Types of Pollination 1. SELF-POLLINATION – Stigma receives pollen from the same plant

2. CROSS-POLLINATION – POLLEN FROM ONE PLANT IS CARRIED TO STIGMA OF ANOTHER OF SAME TYPE OF PLANT ALLOWS FOR EXCHANGE OF GENETIC MATERIAL

FERTILIZATION IN FLOWERS

After the pollen grain lands on the stigma, the pollen tube cell grows a tube to the ovary. The two sperm cells move through the tube into the ovule

-One sperm joins with the egg in the Ovule. -The other sperm joins with the central cell (2N) to form the endosperm (3N). This process is called double fertilization!!!

After fertilization occurs, the flower dies and the seed develops. Seed Formation After fertilization occurs, the flower dies and the seed develops. Ovule becomes the seed coat which protects the embryo. The zygote divides becoming the embryo. The 3N central cell develops into the endosperm which is food-storage tissue.

The ovary develops into the fruit! Fruits The ovary develops into the fruit!

Parts of a Seed

***Fruits protect the seeds and aid in dispersal*** Fruits can be dry (Nuts and grains) or Fleshy (Oranges, Peaches Tomatoes, Squash,…) ***Fruits protect the seeds and aid in dispersal***

****GERMINATION – Development of the seed into a new plant! Seed Germination Seeds remain dormant until conditions are right for development and growth! ****GERMINATION – Development of the seed into a new plant! Water, oxygen, and warm temperatures are Needed!

Root appears first, then the stem, and finally the leaves

Growth and Development Plants respond to stimuli from the environment This process is called TROPISM POSITIVE TROPISM – growth towards the stimulus NEGATIVE TROPISM – growth away from the stimulus PHOTOTROPISM – Response to light GRAVITROPISM – Response to gravity THIGMOTROPISM – Response to touch

PLANT HORMONES HORMONES – Chemicals made in one part of an organism that cause a change somewhere else *Produced in ROOTS! AUXINS – Growth hormones; cause cells to elongate, inhibit growth of side branches

Auxins and Phototropism Control Tip removed Opaque cap Clear cap Opaque shied over base High concentration of auxin Low concentration of auxin

Apical Dominance Apical meristem Lateral buds Auxins produced in the apical meristem inhibit the growth of lateral buds. Apical meristem removed Without the inhibiting effect of auxins from the apicial meristem, lateral buds produce many branches.

TAKS Review How are chloroplasts and mitochondria alike? Get energy directly from the sun Found in humans Found in plants Responsible for energy conversions Plants give off oxygen in what process? Photosynthesis Aerobic respiration Chemosynthesis Anaerobic respiration

TAKS Review Cont…. Production of Carbon Dioxide and sugar Production of Oxygen and sugar Exposure to light Breakdown of protein Intake of carbon dioxide Intake of oxygen Three of the statements above are stages in photosynthesis. Select and arrange in order 3 stages of photosynthesis. a. 3-4-1 b. 4-3-2 c. 3-5-2 d. 3-6-1

TAKS Review Cont…. 4. What are the function of stomata? a. sugar production b. protection c. gas exchange d. water storage 5. What is the function of xylem? Phloem? a. transport water; transport food b. transport food; transport water