Plant Structures Review and Reinforce pg. 83 3. How do root hairs and vascular tissue help a plant survive? Root hairs enter the spaces between soil particles and absorb water and minerals. They also help anchor the plant. Vascular tissue (xylem and phloem) transport materials away from root, leaves 1. What are the functions of roots? Anchor a plant in the ground, absorb water and minerals from the soil, and sometimes store food. 2. Describe the two types of root systems. Taproot System a long thick, main root with many smaller roots branching off (carrots, dandelions); Fibrous Root System thin fibrous roots that form a tangled mass and take the soil with them when they are pulled (lawn grass, corn)
Plant Structures Review and Reinforce pg. 83 4. What are the functions of stems? Carries substances between the plant s roots and leaves. Provides support for the plant and holds up the leaves so they are exposed to the sun. Some stems store food. 5. How are herbaceous stems and woody stems alike? How are they different? They both carry substances between roots and leaves, provide support, hold leaves up to the sun. Woody stems contain wood, are hard and rigid, many layers of tissue, bark and rings; Herbaceous stems contain no wood and are often green, soft and flexible.
Plant Structures Review and Reinforce pg. 83 6. What are the functions of xylem and phloem? xylem transports water and minerals through the stems and leaves; phloem transports food manufactured in the leaves 7. What do annual rings in a tree reveal about its history? They represent a tree s yearly growth (made of xylem). Xylem cells that form in spring large, have thin walls because they grow rapidly, wide light brown ring. Xylem cells that form in summer small, thick walls, grow slow. One pair of light and dark rings represents one year s growth. Wide rings mean lots of rainfall. 8. What are the functions of leaves? They capture the sun s energy (chloroplast), carry out photosynthesis, contain stomata which are small pores that control the movement of gases in and out of the cell
9. How do stomata contribute to photosynthesis? They open to let in carbon dioxide and allow water vapor and oxygen to leave. They close to conserve water. 10. What is transpiration? The process by which water evaporates from a plant s leaves. 11.What are the three parts of a seed? Embryo young plant inside the seed, stored food embryo uses stored food until it can make its own, seed coat keeps the embryo and its food from drying out (cotyledons- seed leaves) 12. Describe two ways seeds can be dispersed. Wind, water, ejection, animals, humans
13.What is germination? After the seed is dispersed, the embryo begins to grow again and pushes out the seed. Begins when the seed absorbs water, then embryo uses stored food to grow, roots grown downward and leaves grow upward 14. What is the function of flowers? Reproduction a flower is the reproductive structure of an angiosperm
petals Parts of a Flower pg. 85 PISTIL stigma style ovary STAMEN anther filament sepal receptacle
Parts of a Flower Vocabulary pg. 84 1. Anther part of the stamem (male part) that produces pollen 2. Filament part of the stamen (male part), the thin stalk 3. Ovary (female part) protects the seeds as they develop and contains one or more ovules 4. Petal- colorful, leaf-like structures that attract pollinators with their color and scent 5. Pistil - the female reproductive parts, found in the center of most flowers 6. Receptacle - part of a flower stalk where the parts of the flower are attached 7. Sepal the small, leaf-like parts that protect the developing flower 8. Stamen the male reproductive parts 9. Stigma the sticky tip of the pistil (female part) 10.Style slender tube connects the stigma to the ovary(female part)
PLANT REPRODUCTION
WHAT ARE THE STAGES OF A PLANT S LIFE CYCLE? Plants have complex life cycles that include two different stages, the sporophyte stage and the gametophyte stage. In the sporophyte stage, the plant produces spores or seeds which can grow into new organisms. The spore or seed develops into a gametophyte. Pg. 89 In the gametophyte stage, the plant produces two kinds of sex cells: sperm cells and egg cells.
HOW DO PLANTS REPRODUCE? All plants undergo sexual reproduction that involves fertilization. Fertilization occurs when a sperm cell unites with an egg cell. The fertilized egg is called a zygote. Many plants can also undergo asexual reproduction. New plants can grow from the roots, stems, or leaves of a parent plant.
NON-VASCULAR AND SEEDLESS VASCULAR PLANTS Examples of nonvascular plants are mosses, liverworts, and hornworts. Examples of seedless vascular plants are ferns, whisk ferns, club mosses, and horsetails. Need to grow in moist environments. Release spores into their surroundings where they grow into gametophytes. The gametophytes produce egg cells and sperm cells. In order for fertilization to occur, there must be enough water available for the sperm to swim toward the egg.
LIFE CYCLE OF A FERN Pg. 88
GYMNOSPERM LIFE CYCLE (NON-FLOWERING PLANTS) Pg. 90
1. CONE PRODUCTION Pg. 91 Most gymnosperms have reproductive structures called cones. The cones are covered with scales. They produce two types of cones: male cones and female cones. Some gymnosperms produce male cones or female cones only. A few gymnosperms produce no cones.
2. POLLEN PRODUCTION AND OVULE DEVELOPMENT Pollen Pollen is produced by the male cones. Pollen contain cells that will mature into sperm cells. Ovule The ovule is a structure that contains an egg cell. It is located at the base of each scale in the female cone. The ovule later develops into the seed.
3. EGG PRODUCTION Two eggs cells form inside each ovule on the female cone.
4. POLLINATION Pollination is the transfer of pollen from the male reproductive structure to the female reproductive structure. In gymnosperms, wind often carries the pollen from a male cone to a female cone. Some pollen grains become trapped in a sticky substance made by the ovule.
5. FERTILIZATION The ovule closes and seals in the pollen. The scale also closes. A pollen grain makes a tube that grows into the ovule. A sperm cell moves through the tube and fertilizes the egg cell.
6. SEED DEVELOPMENT The ovule develops into a seed. The fertilized egg becomes the seed s embryo. Other parts of the ovule develop into the seed coat and the seed s stored food.
7. SEED DISPERSAL When the seeds are mature, the scales open. The wind shakes the seeds out of the cone and carries them away. Only a few seeds will land in suitable places and grow into new plants.
ANGIOSPERM LIFE CYCLE (FLOWERING PLANTS) Pg. 92
1. FLOWER PRODUCTION Pg. 93 Angiosperms have a reproductive structure called flowers. The male part of the flower is called the stamen (anther and filament) and female part of the flower is called the pistil (stigma, style, and ovary).
2. POLLEN PRODUCTION AND EGG DEVELOPMENT Pollen Pollen grains are produced in the anther. Pollen contains sperm cells. Eggs Inside the ovary, an egg cell is produced in each ovule.
3. POLLINATION A flower is pollinated when a grain of pollen falls on the stigma. Some angiosperms are pollinated by the wind, but most rely on other organisms.
4. FERTILIZATION The pollen grain produces a pollen tube that grows into the ovule. A sperm cell moves through the pollen tube and fertilizes the egg cell.
5. SEED DEVELOPMENT The ovule develops into a seed. The fertilized egg becomes the seed s embryo.
6. FRUIT DEVELOPMENT The ovary develops into a fruit. A fruit is the ripened ovary and other structures that enclose one or more seeds.
7. SEED DISPERSAL Fruits are the means by which angiosperm seeds are dispersed. Animals that eat the fruit help to disperse their seeds by depositing them in new areas.