Crash Course on Plants Movement of Materials, Monocots vs. Dicots, Gymnosperms vs. Angiosperms, Plant Parts and Function, and Reproduction

Movement of materials Vascular System (pgs. 614, 643 – 645) – collection of specialized tissues that bring water and mineral nutrients up from the roots and disperse sugars down from the leaves. Xylem – moves water and dissolved minerals up from the roots to the rest of the plant. Tissue is dead when water moves through it. Phloem – moves the products of photosynthesis out of the leaves to stems and roots. Tissue is living.

Movement of Materials (cont.) Capillary Action – tendency of water to rise in a hollow tube Transpiration – the loss of water vapor from plants Cohesion – ability of water molecules to stick to other water molecules. Allows water to move up the xylem. Adhesion – ability of water to stick to other molecules. Allows phloem to move sugars down the plant and water to stick to the sides of xylem when moving up. Stomata – tiny holes in leaves which close to prevent water loss or open to allow air to move in and out.

Monocot vs. Dicot Monocot Dicot Flowering plant whose embryos have one seed leaf Have parallel veins in long, narrow leaves Flower parts in multiples of 3 Vascular tissues are scattered throughout stem Ex. Corn, wheat, rice, grasses, irises, lilles Flowering plants whose embryos have two seed leaves Have leaves with netlike veins Flower parts occur in multiples of 3 or 5 Vascular tissues are arranged in rings Ex. Most deciduous trees (lose leaves in fall) and peanuts

Gymosperm vs. Angiosperm Gymnosperm (p. 621 – 622) Angiosperm (p. 621 – 622) Seeds not in fruit Most are cone-bearing and evergreen Ex. Cycad, Ginko, and conifers (pines) Seeds in fruit Aka. Flowering plants Ex. Peach tree, dogwood, maple tree

Functions of plant parts (p. 79, 688 – 670) Cell wall – a rigid layer that gives protection, support, and shape to the plant cell. Chloroplast – organelles that carry out photosynthesis. Sepals modified leaves that protect the developing flower. Usually green but can be brightly colored. Petals – modified leaves just inside the sepals which are brightly colored to attract animal pollinators. Stamen – male parts of a flower Filament – a stalk which supports an anther Anther – produce pollen grains, the male gametophyte.

Functions of plant parts (p. 79, 688 – 670) Carpel – the female structure of a flower and is found in the innermost layer of the flower. Stigma – the tip, which is covered with a sticky substance that holds pollen grains when they land there. Style – a tube that leads from the stigma to the ovary Ovary – produces the female gametophyte and is found at the base of the flower.

Functions of plant parts (p. 79, 688 – 670) Seed – (p. 614) structure used by some land plants to store and protect the embryo Endosperm – a food supply for the developing embryo Seed coat – protects the embryo Fruit – (p. 622) the mature ovary of a seed or the fluff surrounding dandelion seeds

Plant Reproduction (p. 671) Male and female gametophytes: pollen grains, the male gametophytes, are produced in anthers. The flower’s ovary contains many ovules, which can each contain a female gametophyte. Pollination: A bee may transfer pollen grains from one flower’s anther to another flower’s stigma. One cell of a pollen grain divides to form two sperm. The other cell forms a tube, down which the sperm travel. Double fertilization: One sperm fertilizes the egg, which develops into an embryo. The other sperm unites with the polar nuclei to form the endosperm. The outer layer of the ovule becomes a protective seed coat.

Plant reproduction continued 4. Seeds and fruit: many seeds develop inside the ovary of each flower. while the seeds develop the ovary tissue develops into the juicy flesh of a fruit. A few seeds will find their way into the soil to grow into new plants

Pigments and light (p. 103) Chlorophyll – light absorbing pigment found in the chloroplasts of plant cells Light absorption – mostly red and blue wavelengths Light reflection – mostly green, since chlorophyll doesn’t absorb it very well

Photosynthesis (p. 104 – 105) Takes place in the chloroplasts found in leaves and stems of plants Light Dependent Reactions – must have light to work Takes place: thylakoid membrane (grana) of the chloroplast Needed: sunlight and 6 water molecules (comes from the roots and is transported up to the leaves) Made: energy (ATP- needed to power the light independent reactions; comes from sunlight) and 6 oxygen molecules (comes from the breakdown of water and is released into the atmosphere)

The equation for the reaction: Photosynthesis (p. 104 – 105) Light Independent Reactions Takes place: stroma (space inside the chloroplast between the thylakoid membrane) Needed: energy (comes from light dependent reactions), 6 carbon dioxide molecules (comes from atmosphere and needed to make sugars) Made: 1 sugar molecule (glucose) The equation for the reaction: 6H2O + 6CO2  C6H12O6 + 6O2