Bio exam #3

Water potential

Determined by solute potential (Ψs) and pressure potential (Ψp).

Water potential formula

Ψ = Ψs + Ψp.

Direction of water movement

From higher water potential to lower water potential.

Effect of increasing solute concentration on water potential

Makes water potential more negative (lower).

Water potential of pure water

0 MPa.

Location of transpiration in plants

Stomata in the leaves.

Definition of transpiration

Loss of water vapor from leaves through evaporation.

Main force pulling water up tall plants

Cohesion-tension mechanism.

Property causing water molecules to stick together

Cohesion.

Property causing water to stick to xylem walls

Adhesion.

Role of transpiration in plants

Creates negative pressure that pulls water from roots to leaves.

Tissue that transports water and minerals

Xylem.

Tissue that transports sugars

Phloem.

What does the pressure-flow hypothesis explain?

Transport in phloem.

Direction sugars move in plants

From source to sink.

Source in sugar transport

Where sugars are produced (usually leaves).

Sink in sugar transport

Where sugars are used or stored (roots, fruits, growing tissues).

How does water enter phloem at the source?

By osmosis.

Three main plant organs

Roots, stems, leaves.

Function of roots

To absorb water/minerals, anchor plant, and store nutrients.

Function of stems

Support plant and transport materials.

Function of leaves

Photosynthesis, gas exchange, and transpiration.

Three plant tissue systems

Dermal tissue, vascular tissue, ground tissue.

Dermal tissue function

Protection and gas exchange.

Vascular tissue function

Transport of water, minerals, and sugars.

Ground tissue function

Photosynthesis, storage, support.

Two main vascular tissues

Xylem and phloem.

Are xylem cells living or dead at maturity?

Dead at maturity.

Are phloem cells living or dead?

Living cells.

Where does plant growth occur?

In meristems.

Effect of apical meristems on plant growth

Causes primary growth (length).

Effect of lateral meristems on plant growth

Causes secondary growth (thickness).

What does secondary growth mainly increase?

Stem and root thickness.

Macronutrients required by plants

Nitrogen, phosphorus, potassium, calcium, magnesium, sulfur.

Micronutrients required by plants

Iron, manganese, zinc, copper, boron, molybdenum.

Where do plants absorb most nutrients?

Roots.

What are mycorrhizae?

Symbiotic relationship between plant roots and fungi.

Benefit to plants from mycorrhizae

Increased nutrient and water absorption.

What do fungi get from mycorrhizae?

Sugars from the plant.

Nutrient that carnivorous plants obtain from insects

Nitrogen.

Example of asexual plant reproduction

Strawberry runners.

Other types of asexual reproduction in plants

Bulbs, tubers, rhizomes, cuttings.

Outcome of asexual reproduction in plants

Produces genetically identical clones.

Male reproductive structure of flowers

Stamen.

Parts of the stamen

Anther and filament.

Female reproductive structure of flowers

Carpel (pistil).

Parts of the carpel

Stigma, style, ovary.

Structure that produces pollen

Anther.

Structure that receives pollen

Stigma.

Location of ovules

Ovary.

Definition of pollination

Transfer of pollen from anther to stigma.

Products of double fertilization

Zygote and endosperm.

Function of endosperm

Provides nutrients to developing embryo.

Where is the embryo sac located?

In the ovule.

Conditions required for seed germination

Water, oxygen, and proper temperature.