Plant Hormones Flashcards
What is a tropism?
A growth effect (not applicable to humans)
How can plants grow?
By making cells but also by stretching muscle (via osmosis)
What is a photoperiod?
A time of light
What is a chemotropism?
When an organism moves to things to grow. For example an animal moving towards food or a plant growing towards light
Other than light what stimuli might a plant react to?
-temperature
-pH of ground
-moisture
-Gravity
What conditions are required for germination?
-good soil pH
-moisture
-air (oxygen)
-exterior forces (hot/cold weather, animals to spread seeds)
-enzymes
What is it called when a plant SHOOT is sensitive to light and gravity
Positive Phototrophic Effect
What is called when a plant ROOT is sensitive to gravity and water?
Negative Phototrophic Effect
OR
Positively Geotrophic/Gravitrophic Effect
What do Gibberelins do
Initiate the germination of seeds
What do Auxins do?
Coordinate growth and Phototrophism in a plant
What does ethene do?
Ripen fruit and control cell division
What is hydrotrophism?
Plants movement towards water for photosynthesis and to support cell structure
What is Thigmotrophism
Plants moving in response to touch (positive is towards touch e.g. vines
Negative it’s from touch e.g. plants that close when touched)
What is etiolation?
When a plant searches for light by bending and “wiggling” around to try and find light to go to which leads to them having a Curley shape
How are auxins used in agriculture?
Weed killers, rooting powders, promote plantlet growth
