Chapter 25 Flashcards
The portion of an organism affected by a particular hormone
Target cell
A substance that is produced in one part of an organism and affects another
Hormone
Tendency of a plant to grow toward a source of light
Phototropism
Regulates cell growth and stimulates cell elongation
Auxins
Response of a plant to the force of gravity
Gravitropism
Causes gravitropism
Auxins
Meristematic area on a side of a stem that gives rise to side branches
Lateral bud
The closer a cell is to the stems tip, the more inhibited it is
Apical dominance
Compounds that are toxic to plants
Herbicides
Plant hormones that are produced in growing roots and in developing roots and seeds
Cytokinins
Growth promoting substance
Gibberellin
One of the minor components of natural gas
Ethylene
Responses of a plant to external stimuli
Tropisms
Response of a plant to touch
Thigmotropism
Flower when days are short
Short day plants
Flower when days are long
Long day plants
Chrysanthemums and poinsettias
Short day plants
Spinach and irises
Long day plants
Plants response to periods of light and darkness
Photoperiodism
Pigment responsible for photoperiodism
Phytochrome
Seals the leaf off from its vascular system
Abscission layer
Plants that live in the desert biome
Xerophytes
Plants that are not rooted in the soil but instead grow directly on the bodies of other plants
Epiphytes
Produced in the apical meristem
Auxins
Produced in growing roots
Cytokinins
Stimulates fruit to ripen
Ethylene
Stimulate the growth of lateral buds
Cytokinins
Produce dramatic increases in size
Gibberellins
Cause dormant seeds to sprout
Cytokinins
Promotes root growth
Auxins
Promotes cell division
Cytokinins
