Plant Biology Review

Flashcards for plant biology review.

Pollinator Attraction Strategies

Strategies flowers employ to attract pollinators, such as vibrant colors, specific petal shapes or markings, and alluring scents.

Pollination

The transfer of pollen from the male part of a flower to the female part, leading to fertilization. Self-pollination occurs within the same flower, while cross-pollination involves different flowers.

Seed Dispersal Methods

Methods plants use to disperse seeds, such as wind dispersal (seeds are light and have wing-like structures), animal dispersal (seeds have hooks or are contained in edible fruits), and water dispersal (seeds are buoyant).

Plant Hormones

Chemical signals that regulate various plant processes, such as fruit ripening, growth, and responses to environmental stimuli.

Phototropism and Geotropism

Growth response to light, causing plants to bend towards a light source. Geotropism is the growth response to gravity, with roots growing downwards and shoots growing upwards.

Human Reliance on Plants

Food, medicine, building materials, and oxygen.

Main Plant Parts

Roots, stems, leaves, and flowers.

Hydrophyte, Mesophyte, and Xerophyte

Hydrophytes are adapted to aquatic environments, mesophytes to moderate environments, and xerophytes to arid environments. Hydrophytes often have reduced root systems and thin cuticles, while xerophytes have thick cuticles and specialized water storage tissues.

Leaves

Leaves are the primary site of photosynthesis. Key characteristics include shape, margin, and veins. Parts include blade, base, apex, margin, midrib, and veins.

Leaf Cross-Section Functions

Cuticle (prevents water loss), epidermis (protection), palisade mesophyll (primary site of photosynthesis), spongy mesophyll (gas exchange), air spaces (facilitate gas exchange), vascular bundle (xylem and phloem for transport), and stoma (regulate gas exchange).

Photosynthesis Equation and Leaf Function

6CO2 + 6H2O -> C6H12O6 + 6O2. Photosynthesis is essential for plant survival as it produces glucose, the plant's energy source. The leaf cross-section components facilitate this by allowing CO2 intake (stoma), water transport (xylem), and light absorption (palisade mesophyll).

Stem Functions and Structures

Support, transport of water and nutrients, and storage of food. Structures include bark, cambium, sapwood, heartwood, and pith. Know the function of each.

Transpiration

The process of water movement through a plant and its evaporation from aerial parts, such as leaves. Root pressure and transpiration pull work together to draw water up the stem.

Translocation

The movement of sugars (produced during photosynthesis) from source tissues (e.g., leaves) to sink tissues (e.g., roots, fruits).

Xylem and Phloem Comparison

Xylem transports water and minerals, while phloem transports sugars. Xylem cells are dead at maturity and have thick walls, while phloem cells are living and have sieve plates.

Root Functions

Anchoring the plant, absorbing water and nutrients, storing food, and conducting water and nutrients to the stem.

Water Uptake in Roots

Plants take in water through roots via osmosis, following the active transport of minerals into the root cells, which creates a water potential gradient.

Plant Root Structures and Roles

Root cap (protects the root tip), root hairs (increase surface area for water and nutrient absorption), cortex (stores food and water).

Flower Parts and Functions

Sepals (protect the flower bud), petals (attract pollinators), stamens (male reproductive structures, produce pollen), pistil (female reproductive structure, contains the ovary).