Take 5: 2/16/11 Rhizome Fronds Female seeds have a bad smell What is the underground stem that anchors a fern called? _______________________ _____________ are the leaves of a fern. What is something unusual about Ginkophyta? Rhizome Fronds Female seeds have a bad smell One known species

Take 5: 3/5/12 The two structures in which plants reproduce is ____________ and ____________. The female reproductive structure of nonvascular plants is called a(n) _____. Liverworts, hornworts, mosses, and ferns are all examples of __________________. Seeds Spores Archegonia Non-Seed Plants

Plant Cells & Tissues Ch 23.1

There are 3 types of plant cells Parenchyma Collenchyma Sclerenchyma

3 types of plant cells Parenchyma most abundant TWO MAJOR FUNCTIONS = STORAGE and FOOD PRODUCTION (Photosynthesis) Also FUNCTIONS TO PRODUCE SAP. large vacuole stores water, starch grains, oils Example: The cells of the white potato.

Parenchyma

3 types of plant cells Collenchyma unevenly thickened cell walls to allow cells to grow FUNCTION = PROVIDE STRENGTH AND SUPPORT arranged in tube-like strands Example: the resilient strands in stalks of celery

3 types of plant cells Sclerenchyma thick and rigid cells at maturity, cells die thick cell wall remains and PROVIDES SUPPORT 2 cell types: fibers & sclerids a) fibers = long thin strandlike cells b) sclereids = irregularly shaped, in clusters (ex: apple core, gritty pear texture)

Sclerenchyma

3 types of plant cells Good Review

Parenchyma Collenchyma Sclerenchyma

4 types of plant tissue Dermal Tissue Ground Tissue Vascular Tissue Meristematic Tissue

Dermal tissues FUNCTION = COVER & PROTECT BODY OF PLANT aka epidermis (tightly packed flattened cells that cover all parts of plant) epidermal cells produce waxy _________ to prevent water loss cuticle

Dermal tissues

Dermal tissues Also has ________ (stomata = plural) to control water loss. Stomata are openings in leaf tissue that control gas exchange. ____________ control opening and closing of stomata. Guard cells regulate water loss from leaf. stoma Guard cells

Dermal tissues

Dermal tissues In addition, the dermal tissue of roots have __________ The function of root hairs is to absorb water and dissolved minerals. root hairs

Dermal tissues Trichomes = hairlike projections on stem (“fuzzy appearance”) They function to reduce H20 evaporation from plant They can also secrete _________ substances to protect plant from predators toxic trichomes

Ground tissue FUNCTION = ASSIST WITH PHOTOSYNTHESIS, STORAGE, & SUPPORT Composed mostly of parenchyma cells Located throughout plant Have chloroplasts Ground tissue in stems and roots have _______________ for storing starch grain and water large vacuoles

Vascular tissue FUNCTION = TRANSPORT FOOD, DISSOLVED MINERALS, AND WATER Two types of vascular tissue: xylem & phloem

Vascular tissue Xylem FUNCTION = TRANSPORTS WATER AND DISSOLVED MINERALS FROM ROOTS TO REST OF PLANT tubular shaped cells made of 4 types of cells: a) tracheids b) vessel elements c) fibers d) parenchyma

Vascular tissue Phloem FUNCTION = TRANSPORTS SUGAR AND ORGANIC COMPOUNDS FROM LEAVES TO REST OF PLANT tubular cells joined end to end made up of 2 types of cells sieve tube members (have cytoplasm, no nucleus or ribosomes) companion cell (have a nucleus, help transport sugars thru sieve tubes) large pores at sieve plates exist to allow sugar to move between sieve tube members

Vascular tissue

Vascular tissue

Meristematic tissue tip of root ________________ = region of actively dividing cells where growing plant produces new cells 2 typical types Apical meristem: near tip of roots or stems produce cells that allow roots and stems in become longer Lateral meristem: results in diameter increase of roots and stems Meristem tip of root

Meristematic tissue Lateral meristem: results in diameter increase of roots and stems Example: most woody plants 2 types of lateral meristem = vascular cambium and cork cambium vascular cambium = produces new xylem and phloem cells in stems and roots cork cambium = produces cells with tough cell walls along surface of roots and stems (i.e. bark) 3rd type exists in grasses, corn, & other monocots, where the part of stem between leaves grows (these plants don’t have vascular or cork meristem)

Meristematic tissue

Roots, Stems & Leaves Ch 23.2

Roots Roots function as an _________ and are capable of absorbing _________ and dissolved minerals. They also have _________________ for transporting water & nutrients. anchor water vascular tissue

Roots They vary in shape: short, long, thick, thin, massive, threadlike Ideally roots want a large _____________ for absorbing water and dissolved minerals. surface area

Roots

Roots There are 2 types of root systems (depends on environment). A) taproot = single, thick structures (ex: carrots, beets) B) fibrous roots = many, small branching roots (ex: grasses, clovers)

taproot fibrous root

Root structure Let’s look at the layers within a root, starting out and working our way in. cortex endodermis epidermis pericycle Xylem & phloem INSIDE OUTSIDE

Root structure 5 4 epidermis The outermost structure on a root are ____________________ which increase surface area, ultimately allowing more water, oxygen, & dissolved minerals to be absorbed epidermis 5 Next layer = cortex The cortex transports water and dissolved minerals into vascular tissue Mostly parenchyma cells that store food, water 4

Root structure 3 2 Next layer = pericycle Produces lateral roots Next layer = endodermis A layer of waterproof cell walls around vascular tissue This layer controls water flow & dissolved minerals into roots 3 Next layer = pericycle Produces lateral roots 2

Root structure 1 Xylem & phloem = in center of root monocot = vascular bundles surround central core aka pith dicot = central star 1

Root structure root hairs cortex endodermis epidermis pericycle Xylem & phloem INSIDE OUTSIDE

Makes it longer Protection

epidermis

Root growth Region where roots grow in length = _______________ As these newly created cells mature, they differentiate and take on specific functions. The tip of root is covered by __________ (protective layer of parenchyma cells). Also, vascular cambium in dicots increases the _________ of roots. apical meristem root cap diameter

Stem Supports leaves and flowers Has vascular tissue to transport water, dissolved minerals, sugars Herbaceous or woody Some stems store food (to survive harsh weather) ex: corn, tubers, & rhizomes

Internal structure of stems Vascular tissue appears in 2 arrangements: scattered (monocot) & circular (dicot) monocot dicot

Woody Stems Examples: conifers, perennial dicots (have thick sturdy stems) As plants grow up they also g r o w o u t The added thickness on sides aka “secondary growth.” It is created by the vascular cambium. Woody stems have visible annual growth rings with sclerenchyma fibers

Woody Stems Tissue layers outermost innermost vascular cambium phloem bark xylem outermost innermost Tissue layers

Stems transport materials Xylem transports __________ and dissolved minerals from _________ to _________ Phloem carries dissolved __________, hormones, viruses from __________ to ____________ “sink” = any portion of plant that stores sugars (ex: parenchyma cells) “translocation” = movement of sugars in phloem water roots leaves sugars leaves roots

Growth in Stem primary growth The term “primary growth” refers to a plant increasing in length along the stem at nodes where they give rise to branches and leaves. primary growth

Leaves photosynthesis surface area Primary function = ____________________ Leaves want to have a large ________________ to capture light. Leaf blade = flat broad green structure (vary in size and shape) Some leaves join directly to stem Some leaves have a stalk that joins leaf blade to stem The stalk of a leaf = petiole (has vascular tissue) surface area

leaf blade

Leaf structure Outermost layer = Epidermis Next = Mesophyll: Photosynthesizing tissue of leaf Palisade mesophyll = photosynthesis occurs here Spongy mesophyll = has lots of air pockets for CO2, O2, & water vapor to exit via stomata

Transpiration loss of water via stomata = aka transpiration Think PERSPIRATION… when you sweat you lose water through your pores

Leaf modifications A) Some plants release irritants when crushed or broken B) Another modification = cactus spines which are modified leaves (to reduce water loss). C) Carnivorous plants use their leaves to trap insects. D) Some leaves function as water or food storage sites (ex: aloe vera) E) Bulb = shortened stem, flower bud and immature leaves ex: onion, tulips, narcissus, lilies