DP Biology Vocabulary - 9 Plant Science AHL

Adhesive property

the joining of two different substances due to attractive forces that hold them, such as keeping the water drops on the surfaces of leaves.

Capillary tubing

a tube of small internal diameter that holds liquid by capillary action.

Cohesive property

the sticking together of similar molecules, such as one water molecule being attracted to another water molecule. It also causes water molecules to form drops.

Osmosis

net movement of water molecules through a semi-permeable membrane from an area of higher water potential to an area of lower water potential.

Potometer

a device used for measuring the rate of water uptake of a plant due to photosynthesis and transpiration.

Water tension

the force created by evaporation of water coupled with the cohesive and adhesive forces in plants, enough to support a column of water against the forces of gravity in plants and trees.

Transpiration

the loss of water by evaporation in terrestrial plants, especially through the stomata (accompanied by a corresponding water uptake from the roots).

Xylem

the woody tissue which supports and transport water in vascular plants.

Active transport

a transport mechanism where ions or molecules move against a concentration gradient, this movement requires energy.

Hydrostatic pressure gradient

the stress that develops when solutions containing different concentrations of solute in a common solvent are separated by a membrane that is permeable to the solvent, but not the solute.

Incompressibility of water

the incapability of water to lose volume in response to pressure.

Osmosis

the diffusion of fluid through a semi-permeable membrane from a solution with a low solute concentration to a solution with a higher solute concentration until there is an equal concentration of fluid on both sides of the membrane.

Phloem

the food-conducting tissue of vascular plants that conducts synthesized nutrients to different parts of the plants.

Sieve tubes

an element of phloem tissue consisting of a longitudinal row of thin-walled elongated cells with perforations in their connecting walls through which food materials pass.

Auxin

a plant hormone that causes the elongation of cells in shoots and is involved in regulating plant growth.

Meristem

a region of plant tissue, found chiefly at the growing tips of roots and shoots and in the cambium, consisting of actively dividing cells forming new tissue.

Micropropagation

the propagation of plants by growing plantlets in tissue culture and then planting them out.

Shoot apex

the tip of a shoot, the apical or lateral shoot meristematic dome together with the leaf primordial, from which emerge the leaves and sub-adjacent stem tissue.

Stem

the main body or stalk of a plant or shrub, typically rising above ground, but occasionally subterranean.

Tropisms

the turning or bending movement of an organism or a part of an organism toward or away from an external stimulus, such as light, heat, or gravity.

Fertilization

the action or process of fertilizing an egg or a female animal or plant, involving the fusion of male and female gametes to form a zygote.

Flowering

the process of producing conspicuous flowers.

Mutualistic relationship

an association between organisms of two different species in which each member benefits.

Pollination

the process of transfer of pollen from the anther to the stigma of a plant.

Shoot apex

the tip of a shoot, the apical or lateral shoot meristematic dome together with the leaf primordial, from which emerge the leaves and sub-adjacent stem tissue.

Adhesive property

the joining of two different substances due to attractive forces that hold them, such as keeping the water drops on the surfaces of leaves.

Capillary tubing

a tube of small internal diameter that holds liquid by capillary action.

Cohesive property

the sticking together of similar molecules, such as one water molecule being attracted to another water molecule. It also causes water molecules to form drops.

Osmosis

net movement of water molecules through a semi-permeable membrane from an area of higher water potential to an area of lower water potential.

Potometer

a device used for measuring the rate of water uptake of a plant due to photosynthesis and transpiration.

Water tension

the force created by evaporation of water coupled with the cohesive and adhesive forces in plants, enough to support a column of water against the forces of gravity in plants and trees.

Transpiration

the loss of water by evaporation in terrestrial plants, especially through the stomata (accompanied by a corresponding water uptake from the roots).

Xylem

the woody tissue which supports and transport water in vascular plants.

Active transport

a transport mechanism where ions or molecules move against a concentration gradient, this movement requires energy.

Hydrostatic pressure gradient

the stress that develops when solutions containing different concentrations of solute in a common solvent are separated by a membrane that is permeable to the solvent, but not the solute.

Incompressibility of water

the incapability of water to lose volume in response to pressure.

Osmosis

the diffusion of fluid through a semi-permeable membrane from a solution with a low solute concentration to a solution with a higher solute concentration until there is an equal concentration of fluid on both sides of the membrane.

Phloem

the food-conducting tissue of vascular plants that conducts synthesized nutrients to different parts of the plants.

Sieve tubes

an element of phloem tissue consisting of a longitudinal row of thin-walled elongated cells with perforations in their connecting walls through which food materials pass.

Auxin

a plant hormone that causes the elongation of cells in shoots and is involved in regulating plant growth.

Meristem

a region of plant tissue, found chiefly at the growing tips of roots and shoots and in the cambium, consisting of actively dividing cells forming new tissue.

Micropropagation

the propagation of plants by growing plantlets in tissue culture and then planting them out.

Shoot apex

the tip of a shoot, the apical or lateral shoot meristematic dome together with the leaf primordial, from which emerge the leaves and sub-adjacent stem tissue.

Stem

the main body or stalk of a plant or shrub, typically rising above ground, but occasionally subterranean.

Tropisms

the turning or bending movement of an organism or a part of an organism toward or away from an external stimulus, such as light, heat, or gravity.

Fertilization

the action or process of fertilizing an egg or a female animal or plant, involving the fusion of male and female gametes to form a zygote.

Flowering

the process of producing conspicuous flowers.

Mutualistic relationship

an association between organisms of two different species in which each member benefits.

Pollination

the process of transfer of pollen from the anther to the stigma of a plant.

Shoot apex

the tip of a shoot, the apical or lateral shoot meristematic dome together with the leaf primordial, from which emerge the leaves and sub-adjacent stem tissue.