Plant Systems On the following slides, the green sections are the most important – Underlined words = vocabulary! Hyperlinks are shown in purple. Background Image

o The Texas Bluebonnet (Lupinus texensis) is our state flower and a plant native to Texas. o Remember that plants are NOT dead, but very much alive and composed of eukaryotic cells! o In this unit we will discuss the systems in plants, specifically transport, reproduction, and response. Introduction Image

o Plants are multicellular eukaryotes w/ cell walls made of cellulose. o Plants are autotrophs that carryout photosynthesis to obtain energy. o To carry out cellular functions, plants need: o Sunlight o Water o CO 2 o Minerals Review of Plant Cells

6CO 2 + 6H LIGHT C 6 H (Carbon dioxide) (water) (glucose) (oxygen) o Photosynthesis – the process by which autotrophs convert light energy and carbon dioxide into glucose as a food source for the plant. Review of Photosynthesis

o Plants have cell differentiation (different cell types perform specific functions). o EX Root cells, stem cells, and flower petal cells all have specific functions (jobs) that they carry out for the plant. o AKA Cell Specialization Cell Differentiation DifferentiationPlant.png

o Roots are specialized underground organs that absorb water and minerals necessary for the plant and anchor [hold] the plant in the soil and help to prevent soil erosion. o tap root – (ex: carrot) single large central root o fibrous root – (ex: grasses) clump of short threadlike divisions Absorption via Roots

o Stems are specialized tissues that support leaves to hold them up to sun, and transport water, sugars, and nutrients through the plant. o Some stems are also modified for glucose [sugar] storage areas. Transport via Stems

o Just like in animals, vascular tissues transport materials for plants. o Xylem – transports water (L for liquid) via capillary action in stacked cells to form straw-like drinking tubes; movement is up from roots to leaves o Phloem – transports glucose; movement can be up and down Transport Cont. AAF0/BmCafNOYe6A/s400/xylem1%5B1%5D.gif

o Leaves are the tissues where most photosynthesis, and transpiration [evaporation from plants] occurs. o Veins run through the leaves, transport water, glucose, minerals, etc. to the plant cells Photosynthesis via Leaves

o Stomata are openings in leaf tissue, much like the pores in our skin, used for gas exchange. o Guard cells control the opening and closing of stoma; the cells surround the opening contain numerous mitochondria for energy conversion Photosynthesis Cont. rviews/stoma_diagram.gif

muenchen.de/plant/static/images/blumeninschwabenArabidopsisTha liana.jpg Stomates forming cells in Arabidopsis thaliana. Image

o Flowers are a reproductive organ (not all plants have flowers) with male and female parts. o pollination – transporting pollen (male sperm) to female part (ovule) o fertilization – union of sperm with egg (creates a development of a plant embryo [seed] which grows into a mature plant). Reproduction via Flowers

o Male o Stamen – consist of the anther (produces pollen) and filament (supports anther) o Pollen – contains sperm o Female o Pistil – consists of the stigma, (where pollen lands), style, (connects stigma to ovary), and the ovule (develops into the fruit) o Ovule – develops into an egg, eventually becomes the seed when fertilized o Non-sexual o Petals – colored parts, attract pollinators (EX bees) o Sepals – green parts, protect flower parts Flowers Cont.

Flower Flower Cont. Flower

o Fruits develop from a flower’s female reproductive structure(s), and sometimes other parts too. o The fruits contain the seed(s) o provide a means to spread and disperse the seed(s) and/or as a food source [rich in nutrients] for the germinating seed. o EX fleshy fruit like strawberries, apples, tomato, o EX dry fruit like walnuts and acorns Reproductive Tissues - Fruit kitchen/food/fruits/tropical-fruits_4.jpg

o Seed Plants form seeds (a plant embryo surrounded by a food supply) in order to reproduce. o Seeds are encased in a protective covering called a seed coat. o Video Video Reproductive Tissues – Seeds seeds/seed.gif es_rev/seed-pics.jpg

o Seedless plants do not form hard seeds (EX mosses and ferns) and therefore these plants MUST have water in order for the sperm to swim to the egg.. Seedless Reproduction urse/Diagrams/c10/c10-4fern.gif Photo and caption by Bente Haarstad

o Just like animals, plants respond to changes in their environments (called tropism) – Tropism AnimationTropism Animation o There are four main types of tropisms: o Gravitropism/Geotropism = response in plants that make it grow either with the pull of gravity or against itit o Hydrotropism = response that bends it towards water o Phototropism = response that bends it towards lightlight o Thigmotropism = response that bends it around an object (EX a vine wrapping around an arbor) object Response

Response Cont.

o Another type of response, specifically to changes in pressure, is called a nastic response. o The most common example is the infamous Venus flytrap which closes its leaf when the plant senses an insect to digest nutrients using enzymes. o Nastic Slideshow Nastic Slideshow Response Cont.

Plant Hormones Hormones o A hormone is a chemical produced in one part of an organism that is transported to another part where it causes a physiological change - plant hormones regulate the growth and development in plants – o Some hormones include: o Auxins – promote cell elongation and growth o Gibberellins – promote cell elongation, bud development and seed germination o Cytokinins – stimulate mitosis and cell division Image

o Plants provide consumers with oxygen to breathe, food, shelter, as well as cleaning the air and water for the planet. o Just like animals, plants are active responders within various environments to survive and thrive. o Their use and importance is numerous; humans use plants with healing properties in medical treatments.medical treatments Conclusion PhotographPhotograph by Luis del Río