Overview of Plant Biology Concepts.pdf

🌱 9/3/24, 9:11 PM Overview of Plant Biology Concepts Plant Biology Structure of Plants Anatomy of a Seed Seed Coat: Protects the seed from its environment and stores nutrients for the emb...

🌱 9/3/24, 9:11 PM Overview of Plant Biology Concepts Plant Biology Structure of Plants Anatomy of a Seed Seed Coat: Protects the seed from its environment and stores nutrients for the embryo. Radical: The young root that grows into the full root once the seed sprouts. Hypocotyl: The young shoot. Epicotyl: The shoot tip. Plumule: The young leaves. Primary vs. Secondary Growth Primary Growth: Vertical growth at apical meristems. Secondary Growth: Growth of vascular cambium, secondary xylem, secondary phloem, and cork cambium. Plant Structures Ground Tissue: Provides structural support. Parenchyma: Filler tissue, makes up the bulk of the plant. "Parents buy groceries in bulk to support their kids." Collenchyma: Provides extra support, especially in areas with irregular cell walls. "Colin is a growing team and has irregular moods." Sclerenchyma: Main support, thickest wall. "S for structural support." Vascular Tissues Phloem: Transports sugars through the plant. Xylem: Transports water. Dermal Tissue: Protects the plant and regulates responses to the environment. Epidermis: Also called the dermal tissue, regulates water permeability and gas exchange. Cuticle: Limits water evaporation, similar to the function of human skin. Root Structure Root Hairs: Increase the surface area of the root, allowing for improved water and nutrient uptake. Casparian Strip: Regulates the flow of substances into the root, similar to the liver filtering blood in the human body. Leaf Structure Stomata: Openings in the lower epidermis responsible for gas exchange, surrounded by Guard Cells. Palisade Mesophyll: Site of photosynthesis. Spongy Mesophyll: Site of gas exchange. Bundle Sheath Cells: Protect vascular bundles from air exposure. Characteristics of Plants Transpiration: Water evaporation from stems and leaves. Transpirational Pull: As water evaporates, it creates a negative pressure that pulls water upwards. Capillary Action: Surface tension causes water to climb and move upwards. https://www.turbolearn.ai/content/152c16db-47dd-45c7-a519-544f7b9c0096 1/3 9/3/24, 9:11 PM Overview of Plant Biology Concepts Root Pressure: Osmotic flow of water into the roots due to high solute concentration. Movement of Nutrients Pressure Flow Hypothesis: High concentration of sugars in phloem creates an osmotic gradient, causing water to move in and create pressure. "Add pressure to the phloem in the leaves, and the sugar or water will flow to the roots." Plant Hormones Ethylene: Helps ripen fruit. Auxin: Promotes cell growth, causes tropism (phototropism, gravidotropism, thigmotropism). Corkinins: Induce cell differentiation and division. Gibberellins: Induce flowering, fruit production, stem elongation, leaf and fruit death. Abscisic Acid: Promotes dormancy, inhibits growth during times of stress. Alternation of Generation Homospores: Plants that create one type of spore. Heterospores: Plants that create two types of spores. Microspores: Male gametophytes. Megaspores: Female gametophytes. Bryophytes: Nonvascular plants, including mosses, hornworts, and liverworts. Tracheophytes: Vascular plants, including xylem and phloem and roots. Plant Classification Type Characteristics Bryophytes Nonvascular, no roots, gametophyte stage Tracheophytes Vascular, xylem and phloem, roots, sporophyte stage Seedless Tracheophytes Lycophytes and pterophytes Seed-bearing Tracheophytes Gymnosperms and angiosperms Reproductive Parts Petals Stamen: Male sex organ Pistil: Female sex organ, includes stigma, style, and ovary## Angiosperms: Monocots vs Dicots 🌼 The reproductive parts of a flower can be divided into male and female parts. The male part is called the stamen. Angiosperm Characteristics Cotyledons: the first leaves that emerge from a seedling Vascular bundles: groups of specialized tissues that transport materials throughout the plant Root system: the underground structure of a plant that absorbs water and nutrients Monocot Characteristics https://www.turbolearn.ai/content/152c16db-47dd-45c7-a519-544f7b9c0096 2/3 9/3/24, 9:11 PM Overview of Plant Biology Concepts Characteristic Description Cotyledons 1 Leaf Veins Parallel Vascular Bundles Complexly arranged Root System Fibrous Floral Parts Multiply in 3s Dicot Characteristics Characteristic Description Cotyledons 2 Leaf Veins Net-like Vascular Bundles Arranged in rings Root System Taproot Floral Parts Multiply in 4s or 5s Nitrogen Cycle 🌱 Nitrogen is an essential nutrient for plants, but it's not always readily available. That's where nitrogen-fixing bacteria come in! Nitrogen-Fixing Bacteria "These bacteria take atmospheric nitrogen (N2) and convert it into ammonia (NH3), which can then be used by plants." Nitrogen Cycle Steps Nitrogen-fixing bacteria: convert ammonia (NH3) to nitrite (NO2-) Nitrifying bacteria: convert nitrite (NO2-) to nitrate (NO3-) Plants: absorb nitrate (NO3-) from the soil Decomposition: ammonia (NH3) is released from waste and decaying matter By mastering these concepts, you'll be well on your way to acing your plant biology test! 😊 https://www.turbolearn.ai/content/152c16db-47dd-45c7-a519-544f7b9c0096 3/3