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Pip's Plants AP 1
Part one of plant cards 910417
Question | Answer |
---|---|
Plants | Evolved from green algae (Protista) Cell walls of cellulose Stores surplus carbohydrates as starch |
Plants | Most moved to land 475 million years ago The plant body lives simultaneously in air and in soil (presents a challenge) |
Bryophytes | grow close to ground because they lack vascular tissue and ligin-fortified tissue that enables plants to grow tall on land. Ex mosses and liverworts |
Tracheophytes | Plants with xylem and phloem. Includes all plant except mosses and liverworts. Ex gymnosperms and angiosperms |
gymnosperms | seeded cone-bearing plants (conifers). Have many modifications for dry environments (needlelike leaves). Ex. pine, juniper, cedar, sequoia. |
Angiosperms | Flowering plants. Seed is hidden inside ovary. Most divers plants on Earth. Types: monocots and dicots. Ex. roses, daisies, nut and fruit trees. |
Moncots | Seed consists of one part. Veins in leaves are parallel. Roots are fibrous. Ex. grasses and corn |
Dicots | seed consists of two parts. Veins in leave are netlike. Roots are taproots. Ex. roses, daisies, oak and maple trees |
Dermal tissue | Protection- acts as the skin of the plant. Absorption- root hairs are modified epidermal cells |
Vascular tissue | xylem and phloem |
Xylem | Carries water and minerals from roots to leaves. Main component of wood. |
phloem | Carries food from leaves to nonphotosynthetic parts of plants. Consists of sieve tube and companion cells. |
ground tissue | support, photosynthesis, storage parenchyma, collenchyma, sclerenchyma |
Types of plant cells | parenchyma, collenchyma, sclerenchyma |
Parenchyma | Typical plant cell. Single, large vacuole. Thin, flexible cell wall. Functions are: photosynthesis, storage, synthesis. Regenerating an entire plant from a single parenchyma cell is possible. |
Collenchyma | Type of ground tissue. Uneven and thick primary cell walls. Provide support for young plants. Make up the "strings" of celery. |
Sclerenchyma | Type of ground tissue. Have thick secondary cell wall. Make up xylem tracheids, and vessels. Sclereids and fibers |
Sclereids (sclerenchyma) | nutshells, seed coats, and grittiness in pears |
Fibers (sclerenchyma) | hemp, rope, linen |
Sporopollenin | A complex polymer responsible for making the walls of plant spores tough and resistant to harsh environmental conditions |
Reasons stomates close | Guard cells lose water and become flaccid. Plants dehydrate. Temperatures are high. Abscisic levels increase. |
Reasons stomates open | During photosynthesis, guard cells make sugar, causing decrease in water potential. Guard cells absorb water and become turgid. Light stimulates sensors in plasma membrane. CO2 levels inside leaf decrease. |
Plasmodesmata | continuous pathway from cytosol to cytosol between adjacent cells |
Symplast | system of plasmodesmata |
Apoplast | the extracellular pathway formed by the connection of all the adjacent cell walls of neighboring plant cells. |
Aquaporins | Membrane channels specific for passive, rapid transport of water into or out of a cell. Found in both plant and animal cells. |
Transpiration and Rate increase | Transpiration is the loss of water through the stomates of the leaf. The rate increases due to: High Temperature, Wind, Low Humidity |
Transpirational pull-cohesion tension theory | As one molecule of water evaporates from the leaves, one molecule of water is drawn in through the roots. Requires no energy. Water flows from high to low water potential |
Sap movement down a tree | Sap flows down and around the phloem of tree by active transport by a process called translocation |
Tap Root | Characteristics of dicots. Consists of one large, vertical root. Stores food. Ex. Carrots, turnips, sugar beets |
Fibrous Root | Common in monocots, like grasses. Anchors plants firmly in soil. |
Adventitious | Roots that grow above the ground. Corn has above-ground roots that prop up the plant. English ivy and mangrove trees have aerial roots. |
Functions of Roots | Anchorage. Storage. Absorption. |
Kranz Anatomy | Refers to the structure of C-4 leaves. No palisade layer. Bundle-sheath cells lie under mesophyll, both cells tightly surround veins |
Hatch-Slack Pathway | A different biochemical pathway that precedes the Calvin cycle and pumps CO2 from mesophyll into bundle sheath cells where the Calvin cycle occurs. |
Gametangia | Reproductive organ of bryophytes |
Archegonium | Female gametangia-produces eggs. Found in gymnosperms and bryophytes. Fertilization occurs here |
Antheridium | Male gametangia- produces sperm. Found in gymnosperms and bryophytes. |
Gametophyte/Sporophyte generations | Major characteristic of the sexual life cycle of plants. The monoploid and diploid generations alternate |
Gametophyte generation | the n or monoploid generation, dominates in primitive plants like mosses. |
Sporophyte generation | the 2n or diploid generation; dominates in flowering plants |
Alternation of generations in Mosses | the n generation is the more conspicuous and dominant; the 2n plant grows out from the n plant, it is smaller and exists for a short time |
Alternation of generation in Ferns | the n and 2n generations are independent of one another although the 2n generation is larger |
Alternation fo generation in Flowering plants | the 2n generation is dominant; the n generation, which consists of eggs and sperm, is dependent on the 2n generation; the n generation develops inside the sporophyte generation |
Vegetative Propagation | Asexual reproduction in plants. Plants clone themselves from plant parts, stems, roots, and leaves. Offspring are identical to the parent. Ex. cuttings, runners, bulbs, grafting |
Mychorrizae | Mutualistic relationship between fungi and roots of almost all vascular plants. Enhances uptake of water and selected minerals. |
Rhizobium | Mutualistic relationship between bacteria and roots of legumes. Helps fix nitrogen gas from the air into a form the plant can utilize. As a result of the increased nitrate uptake, these plants have a high protein content. |
Plant sexual reproduction | Double fertilization. One sperm fertilizes the ovum and becomes the embryo (2n). The other sperm fertilizes two polar bodies and becomes the cotyledon. After fertilization, the ovule becomes the seed and the ovary becomes the fruits. |
Seed | Consists of the sporophyte (2n) embryo packaged with food supply (cotyledon) inside a protective coat (the seed coat). Developed from the ovule of a flower |
Fruit. | Ripened ovary. Contains seeds. |
Apical Dominance | Promotes growth of apical shoots (primary growth). Inhibits development of axillary buds (secondary growth) |
Tropism | Movement (growth) of a plant toward or away from stimuli. Ex: phototropism, gravitropism, thigmotropism |
Positive Tropism | Growth toward a stimuli |
Negative Tropism | Growth away from a stimuli |
Gravitropism | Roots display a positive gravitropism while shoots display a negative gravitropism |
Statoliths | Specialized plastids that contain starch grains that sink to the low points in cells. Help plants responds to gravity. |
Plant hormones | Help coordinate growth, development, and responses to environmental stimuli. Produced in minute concentrations |
Examples of plant hormones | auxins, cytokinins, gibberellins, abscisic acid, ethylene |
Auxins | Plant hormone. Produced in meristem tissue of apical buds and embryo. Responsible for APICAL dominance. Stimulates cell elongation, root growth, development of fruit. |
Auxins | Unequal distribution of auxins are responsible for phototropism. Used as rooting powder to help the cut end of a plant grow new roots. |
Cytokinin | Plant hormone. Synthesized in actively growing tissue. Stimulates cell division and growth. Delays aging (senescence) |
Gibberellin | Plant hormone. Discovered in rice fungus.. stimulates stems and leave to grow long. When applied to dwarf pea plants, the plants grow to normal height. Causes plant to grow a long stem during bolting. |
Abscisic Acid (ABA) | Plant hormone. Inhibits growth and cell division. Promotes plant and seed dormancy. |
Ethylene | A gaseous plant hormone. Responsible for fruit ripening. Given off by ripe fruit. Promotes leaf abscission (loss of leaves) |
Leaf abscission | Loss of leaves. |
Phytochrome | Regulates many responses to light throughout a plant's life from germination of seeds to flowering. Is a photoreceptor that is sensitive to red light. |