Plant Hormones Flashcards
What are plant hormones?
Plant hormones are organic compounds that are made in one part of the organism and then transferred to another part of the organism where there’s an effect
What do plant hormones affect?
Cell division, growth, and differentiation
How do plant hormones work?
they chemically bond to plasma membranes at specific sites of the organism called receptor proteins
What are the 4 functions of auxins?
plant hormone that stimulates the lengthening of cells, promotes apical dominance (lengthens upward), promotes the setting of fruits, and prevents the dropping of fruits
Where are auxins produced?
in apical meristems, buds, young leaves, and tissues
What is the most widely studied auxin?
IAA
What are the 4 functions of Gibberellins?
promotes cell elongation, promotes seed germination, increase the size of fruits, overcome bud dormancy
What is the function of ethylene and what is it known for?
promote the ripening of fruits, known for being the only gaseuos hormone
How does ethylene transport?
it diffuses through the spaces between cells and transported within phloem
Where is ehtylene found?
tissues of ripening fruits, dying leaves and flowers
What is the function of cytokinins?
promotes cell division through needed proteins for mitosis, and promotes lateral bud growth
What are the functions of abscisic acid?
promotes stomatal closure, promotes dormancy, inhibits other hormones, blocks growth, increases abscission
What are the two types of plant responses?
tropic response, nastic response
What is tropic response?
plant response in which the plant grows away or toward the environmental stimulus
What is the difference between positive and negative tropism?
positive is toward, negative is away
What is phototropism?
Plant growth where the response to light is caused by uneven distribution of auxin
What is Heliotropism?
the motion of plants following the movement of sun
What is Thigmotropism?
plant growth in resposne to mechanical stimuli like through an object
What is Gravitropism?
plant growth in reponse to gravity
What is Chemotropism?
plant growth in response to a chemical
What are nastic responses?
plant response where movement is independant on direction of stimuli NOT A GROWTH RESPONSE
What are the two types of nastic responses?
Thigmonastic response, nyctinastic response
What is thigmonastic movements?
movement due to touching the plant ex: venus fly trap
What is nyctinastic movements?
movement due to daily cycle of light and dark causing movement of water in cells
