BIO1106 FINAL

What adaptations help prevent desiccation?

Cuticle (waxy layer) and stomata

What structures allow transport in plants?

Xylem (water/minerals) and phloem (sugars)

What is a haplodiplontic life cycle?

Alternation of generations between haploid gametophyte and diploid sporophyte

Which generation is dominant in bryophytes?

Gametophyte

Which generation is dominant in vascular plants?

Sporophyte

What defines bryophytes?

Non-vascular, gametophyte dominant, require water for reproduction

What defines tracheophytes?

Vascular plants with xylem and phloem, sporophyte dominant

What are lycophytes?

Vascular plants with roots/stems, no seeds, need water for fertilization

What are pterophytes?

Ferns; vascular, no seeds, water needed for fertilization

What are seed plants?

Plants that produce seeds (gymnosperms + angiosperms)

Advantages of seeds?

Protection, food supply, dispersal, dormancy

What does gymnosperm mean?

“Naked seed” (not enclosed in fruit)

Main gymnosperm group?

Conifers

What defines angiosperms?

Flowers, fruits, enclosed seeds

What is double fertilization?

One sperm → zygote (2n), one sperm → endosperm (3n)

What is pollen?

Male gametophyte that transports sperm

What are meristems?

Regions of cell division

Apical meristems function?

Primary growth (length)

Lateral meristems function?

Secondary growth (thickness)

Three tissue systems?

Dermal, ground, vascular

Function of xylem?

Transport water/minerals upward

Function of phloem?

Transport sugars (up or down)

What is water potential (Ψ)?

Measure of potential energy driving water movement

Equation for water potential?

Ψ = Ψs (solute) + Ψp (pressure)

Direction of water movement?

High Ψ → low Ψ

What is transpiration?

Evaporation of water from leaves

What forces move water up xylem?

Cohesion, adhesion, tension

What is cavitation?

Air bubbles breaking water column

Three pathways for water movement?

Apoplastic, symplastic, transmembrane

Function of Casparian strip?

Blocks passive flow, forces selective uptake

Role of root hairs?

Increase surface area for absorption

What is translocation?

Movement of sugars through phloem

Source vs sink?

Source = sugar producer, Sink = sugar user/storage

What drives phloem movement?

Pressure-flow hypothesis

Difference between macronutrients and micronutrients?

Macro = large amounts, Micro = small amounts

Why is nitrogen important?

Needed for proteins and nucleic acids

What is nitrogen fixation?

Conversion of N₂ → usable forms (NH₃, NO₃⁻)

Role of mycorrhizae?

Increase nutrient absorption

Physical defenses in plants?

Cuticle, bark, thorns, trichomes

Chemical defenses?

Toxins, defensins, secondary metabolites

What is systemic acquired resistance (SAR)?

Whole-plant defense after infection

Function of auxin?

Cell elongation

Function of cytokinins?

Cell division, lateral growth

Function of ethylene?

Fruit ripening

Function of abscisic acid?

Dormancy and stomatal closing

Phototropism?

Growth toward light

Gravitropism?

Growth in response to gravity

Thigmotropism?

Growth in response to touch

What is alternation of generations?

Switching between haploid and diploid stages

What is pollination?

Transfer of pollen to stigma

Self vs cross pollination?

Self = same plant, Cross = different plants

What is vernalization?

Flowering triggered by cold period