2Multicellular eukaryotes Cell walls made of celluloseDevelop from multicellular embryosCarry out photosynthesis using Chlorophyll a & bMost are autotrophsSome are parasites
3Plant Life Cycle 2 phases that alternate: Dipoloid Haploid Known as alternation of generations
4Mitosis & meiosis alternate to produce 2 types of reproductive cells GametesHaploid phase is called a gametophyteSporesDiploid phase called sporophyte
5Survival In order to survive, plants need: sunlight water and minerals gas exchangetransport of water and nutrients throughout the plant body
6Evolution of PlantsThe first plants evolved from an organism similar to the multicellular green algae living todayThe oldest known plant fossils, about 450 million years old, are similar to today’s mosses
7Division of the Plant Kingdom Plants are divided into four groups based on these features:water-conducting tissuesseedsflowers
8Evolutionary Relationships Among Plants Flowering plantsCone-bearing plantsFerns and their relativesFlowers; Seeds enclosed in fruitMosses and their relativesThis cladogram shows the evolutionary relationships among the various groups of plants. The four main groups of living plants are mosses and their relatives, ferns and their relatives, cone-bearing plants, and flowering plants.SeedsWater-conducting (vascular) tissueGreen algae ancestor
9Seed plants are divided into two groups: Gymnosperms bear seeds directly on the surfaces of cones.Angiosperms, or flowering plants, bear seeds within a layer of tissue that protects the seed
10Adaptations that allow seed plants to reproduce without water include: flowers or conesthe transfer of sperm by pollinationthe protection of embryos in seeds
11The male gametophyte is contained in a tiny structure called a pollen grain This transfer of pollen is called pollination.
12SeedsA seed is an embryo of a plant that is encased in a protective covering and surrounded by a food supply.An embryo is an organism in its early stage of development.The seed coat surrounds and protects the embryo and keeps contents of the seed from drying out.
14AngiospermsThe majority of living plant species are flowering plants, or angiospermsFlowers are an evolutionary advantage because they attract animals, which then transport pollen from flower to flower.Flowers contain ovaries, which surround and protect the seeds.After pollination, the ovary develops into a fruit.A fruit is a wall of tissue that surrounds a seed. A fruit protects the seed and aids in its dispersal.
15There are two classes within the angiosperms— monocots and dicots Monocots and dicots are named for the number of seed leaves, or cotyledons, in the plant embryo. Monocots have one seed leaf, and dicots have two.A cotyledon is the first leaf or the first pair of leaves produced by the embryo of a seed plant
17Life CyclesThere are three categories of plant life spans: annual, biennial, and perennial.Annuals are plants that complete a life cycle in one growing season.Biennials complete their life cycle in two years. In the first year, they germinate and grow roots, short stems, and sometimes leaves. In the second year, they grow new stems and leaves, produce flowers and seeds, and die.Perennials live for more than two years.
18Plant StructureThe three principal organs of seed plants are roots, stems, and leaves.These organs perform functions such as the transport of nutrients, protection, and coordination of plant activities.
19Roots: absorb water and dissolved nutrients. anchor plants in the ground.protect the plant from harmful soil bacteria and fungi.
20Stems provide: a support system for the plant body. a transport system that carries nutrients.a defense system that protects the plant against predators and disease
21Leaves:are a plant’s main photosynthetic systems.increase the amount of sunlight plants absorb.Adjustable pores conserve water and let oxygen and carbon dioxide enter and exit the leaf.
22Plants consist of three main tissue systems: dermal tissuevascular tissueground tissue
24Vascular Tissue Conduct water and nutrients throughout the plant The first vascular plants contained tracheids which are cells specialized to conduct water.Tracheids make up xylem, a transport subsystem that carries water from the roots to every part of a plant.Phloem transports solutions of nutrients and carbohydrates produced by photosynthesis
25Both xylem and phloem can move fluids through the plant body, even against the force of gravity Xylem moves waterPhloem moves food
26Roots The two main types of roots are: taproots, which are found mainly in dicotscarrotsfibrous roots, which are found mainly in monocotsgrasses
27The most important nutrients plants need include: nitrogenphosphoruspotassiummagnesiumcalcium
28Root pressure forces water through the vascular cylinder and into the xylem Root pressure is the starting point for movement of water through the vascular system of the entire plant.
29Stems Stems have three important functions: they produce leaves, branches and flowersthey hold leaves up to the sunlightthey transport substances between roots and leaves
30LeavesThe structure of a leaf is optimized for absorbing light and carrying out photosynthesis
31Leaf Structure . Simple leaf Compound leaf Blade Leaflet Petiole Bud Most of a leaf consists of a blade attached to the stem by a petiole. The blade of a simple leaf (left) can be different shapes. In a compound leaf (right), the blade is divided into many separate leaflets.Simple leafLeafletPetioleBudCompound leafStemCopyright Pearson Prentice Hall
32Stomata are porelike openings in the underside of the leaf that allow carbon dioxide and oxygen to diffuse into and out of the leaf.Guard cells are specialized cells that control the opening and closing of stomata by responding to changes in water pressure.
33Transpiration is the loss of water through its leaves Plants keep their stomata open just enough to allow photosynthesis to take place but not so much that they lose an excessive amount of water
34ReproductionReproduction in gymnosperms takes place in cones, which are produced by a mature sporophyte plant.Gymnosperms produce two types of cones: pollen cones and seed cones
36FlowersFlowers are reproductive organs that are composed of four kinds of specialized leaves: sepals, petals, stamens, and carpels.
37Sepals enclose the bud before it opens and protect the flower while it is developing.Flowers are reproductive organs that include sepals, petals, stamens, and carpels.Sepal
38Petals attract insects and other pollinators to the flower. Petals are often brightly colored and are found just inside the sepals.Petals attract insects and other pollinators to the flower.PetalFlowers are reproductive organs that include sepals, petals, stamens, and carpels.
39The male parts of a flower consist of an anther and a filament, which together make up the stamen.AntherStamenFilamentFlowers are reproductive organs that include sepals, petals, stamens, and carpels.
40An anther is an oval sac where meiosis takes place, producing pollen grains.
41The filament is a long, thin stalk that supports an anther.
42The innermost floral parts are carpels, also called pistils, which produce the female gametophytes. StigmaCarpelStyleFlowers are reproductive organs that include sepals, petals, stamens, and carpels.Ovary
43Each carpel has a broad base forming an ovary. The ovary contains one or more ovules where female gametophytes are produced.Flowers are reproductive organs that include sepals, petals, stamens, and carpels.OvaryOvule
45At the top of the style is the stigma—a sticky portion where pollen grains frequently land.
46Parts of a Typical Flower StigmaAntherStamenFilamentCarpelStyleOvaryOvaryPetalSepalOvule
47Reproduction in angiosperms takes place within the flower Reproduction in angiosperms takes place within the flower. Following pollination and fertilization, the seeds develop inside protective structures
48This illustration shows the life cycle of an iris This illustration shows the life cycle of an iris. The developing seeds of a flowering plant are protected and nourished inside the ovary, which is located at the base of the flower. Reproduction in angiosperms takes place within the flower. After pollination, the seeds of angiosperms develop inside protective structures.
49Seeds are dispersed by animals, wind, and water. Seeds dispersed by animals are typically contained in fleshy, nutritious fruits.Environmental factors such as temperature and moisture can cause a seed to end dormancy and germinate