glossary of important terms
apical dominance: the inhibition exerted on the growth of lateral buds by the terminal bud of a growing plant shoot
autotroph: describes organisms, especially green plants, that are capable of making nutrients from inorganic materials
fertilizer: an organic or synthetic substance usually added to or spread onto soil to increase its ability to support plant growth
geotropism: plant growth or movement in response to gravity. Upward growth of plant parts, against gravity, is called negative geotropism, and downward growth of roots is called positive geotropism.
germination: the process by which plants, fungus and bacteria emerge from seeds and spores, and begin growth.
herbicide: a chemical preparation designed to kill plants, especially weeds, or to inhibit their growth
hormone: a substance synthesized by plants that regulates their growth and development
hydrotropism: movement by a plant part such as a root toward or away from a source of water
macronutrients: a chemical element needed in large amounts by plants for normal growth and development, e.g. nitrogen, carbon, or potassium
micronutrients: a substance that an organism requires for normal growth and development but only in very small quantities, e.g. a vitamin or mineral
minerals: an inorganic substance that must be ingested by animals or plants in order to remain healthy
nastic movement: describes the movement of the parts of a plant in response to external stimuli, e.g. the opening of a crocus flower in response to temperature
pesticide: a chemical substance used to kill pests, especially insects
phototropism: the tendency of an organism to grow toward or away from a source of light
thigmotropism: a directional growth movement tropism of a plant part, especially a tendril, in response to physical contact with a surface
tropism: the involuntary response of an organism or one of its parts toward or away from a stimulus such as heat or light
photosynthesis: a process by which green plants and other organisms turn carbon dioxide and water into carbohydrates and oxygen, using light energy trapped by chlorophyll
respiration: a metabolic process in cells leading to the production of energy by the breakdown of organic substances internal respiration
germination: the process by which plants, fungus and bacteria emerge from seeds and spores, and begin growth.
herbicide: a chemical preparation designed to kill plants, especially weeds, or to inhibit their growth
hormone: a substance synthesized by plants that regulates their growth and development
hydrotropism: movement by a plant part such as a root toward or away from a source of water
macronutrients: a chemical element needed in large amounts by plants for normal growth and development, e.g. nitrogen, carbon, or potassium
micronutrients: a substance that an organism requires for normal growth and development but only in very small quantities, e.g. a vitamin or mineral
minerals: an inorganic substance that must be ingested by animals or plants in order to remain healthy
nastic movement: describes the movement of the parts of a plant in response to external stimuli, e.g. the opening of a crocus flower in response to temperature
pesticide: a chemical substance used to kill pests, especially insects
phototropism: the tendency of an organism to grow toward or away from a source of light
thigmotropism: a directional growth movement tropism of a plant part, especially a tendril, in response to physical contact with a surface
tropism: the involuntary response of an organism or one of its parts toward or away from a stimulus such as heat or light
photosynthesis: a process by which green plants and other organisms turn carbon dioxide and water into carbohydrates and oxygen, using light energy trapped by chlorophyll
respiration: a metabolic process in cells leading to the production of energy by the breakdown of organic substances internal respiration