information about tips and tropes

trippi troppi

Darwin - when, what, result

1880-first, playing around with tip and coverings, the tip has something to do with bend

Darwin - variables 

(may have multiple answers)

independent/manipulated = tip cover

constant = light source

dependant = bend

Boysen-Jensen - when, what, result

1913, covered different sections with a barrier, something must be diffusing on the side with shade

Botsen-Jensen - Variables

Independent/Manipulated - type of barrier

responding - bend

constant - light source

Paal - when, what, result

1919, tip decapitated and replaced off centre, growth isn’t affected by the sun but by somewhere in the tip

Paal - variables

Independent/Manipulated - tip. being cut off and placed off-centre

responding - bend

constant - no light

Went - when, what, result

1926, tip was incubated on a gelatin block,the  then that gelatin block was placed onto the stem but off-centre, the growth hormone was difusing from the tip into the stem.

Went - variables

Independent/Manipulated - tip being cut off, incubated on gelatin, then gelatin replaced off-centre

responding - bend

constant - no light

phototropism - what and advantage

stimulus to light, ensure plant gets lots of light

negative = away from light, positive = towards light

gravitropism - what and advantage

stimulus to gravity, ensure plant goes in right direction, negative = down/with gravity, Positive = up.against gravity

hydrotropism - what and advantage

stimulus to water, ensure roots get water, positive = towards water, negative = away from water

thigmotropism - what and advantage

stimulus to touch, ensure plant gets support and gain more light, positive = towards touch, negative = away from touch

chemotropism - what and advantage

stimulus to chemicals, ensure plant gets the right chemicals, positive = towards chemicals, negative = away from chemicals