Animal and Plant Responses Flashcards
When an organism has favoured traits for its environmental conditions, increasing its chance of survival and reproductive success.
Adaptive advantage
The system that regulates an organism’s innate sense of time and controls circadian/biological rhythms.
Biological clock
A gland or muscle that responds to external stimulation.
Effector
A rhythm that continues without any external cues.
Endogenous rhythm
The synchronisation of biological rhythms by external cues.
Entrainment
A signal or trigger from the environment that can entrain an endogenous rhythm and regulates an exogenous one.
An environmental cue
A pattern that occurs only in response to external cues and which disappear when cues are removed.
Exogenous
The time between the onset of one activity and the next, in the absence of any environmental cues (conditions are constant).
Free-running period
The ability of an animal to find its way home after being displaced.
Homing
Any genetically determined behaviour (can not be learnt).
Innate behaviour
Random movement of a whole organism in response to an environmental stimulus.
Kinesis
The frequency of changing direction is proportional to the intensity of the stimulus.
Klinokinesis
A behaviour that is based on experience, or passed on from one individual to another by imitation.
Learned behaviour
The regular mass movement of organisms from one location to another.
Migration
The ability of an animal to stay on a desired course/find a desired location using external environmental cues.
Navigation
The speed of an animal is proportional to the intensity of the stimulus causing the movement.
Orthokinesis
The amount of time difference between an entrained endogenous biological rhythm when the zeitgeber is removed.
Phase shift
Any part of an organism capable of detecting a stimulus and sending a signal to another part of the organism.
Sensory receptor
The movement of a whole organism or cell in response to an external directional stimulus (environmental). An innate behaviour.
Taxis
An external or environmental cue that entrains (synchronises) an organism’s biological rhythms.
Zeitgeber
A plant hormone that functions in many plant development processes, particularly bud dormacy.
Abscisic acid
The process that makes leaves fall to the ground in autumn.
Abscission
An organism that is able to produce complex organic molecules from a simpler molecule found in its environment, using an external energy source.
Autotroph
Also known as IAA, this is a hormone that affects plant cell elongation in root and shoot tips - controls some plant growth processes.
Auxin
A period of day length that when exceeded, triggers flowering in long-day plants or inhibits flowering in short-day plants.
Critical day length
A hormone that stimulates cell division in the presence of auxin.
Cytokinin
The only hormone in the form of a gas that stimulates plant (fruit) ripening or the falling of mature leaves.
Ethylene
Directional growth response of a plant organ to a gravity stimulus.
Gravitropism
Hormones that stimulate stem elongation and enzymes in germinating seeds.
Gibberellins
Directional growth response of a plant organ to a water stimulus.
Hydrotropism
A plant that is triggers into flowering when nights become shorter than the critical day length.
Long-day plant
A response of a plant organ to a non-directional diffuse (environmental stimulus).
Nastic response
A circadian rhythmic movement of plants in response to the onset of darkness (e.g. the closing of petals of a flower at dusk).
Nyctinasty
The period of time each day during which an organism is exposed to the sun.
Photoperiod
The response of an organism to seasonal changes in the photoperiod.
Photoperiodism
The process by which plants and some bacteria use the energy from the sunlight to produce glucose from carbon dioxide and water.
Photosynthesis
Directional growth response of a plant organ to a light stimulus.
Phototropism
A blue-green pigment found in many plants that regulates various development processes, particularly flowering.
Phytochrome
Any of a range of chemicals that regulate plant growth.
Phytohormone
A plant that is triggered into flowering when nights become longer than a critical day length.
Short-day plant
A nastic response triggered by touch.
Thigmonastic
Directional growth response of a plant organ to a touch stimulus.
Thigmotropism
