Biology Ethylene

8/18/2019 Biology Ethylene

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Name: Brooke Jordan

Title of lab: Plant growth substances- Ethylene

Aim:

1. To demonstrate that ripened fruits produce a substance whichpromotes ripening.2. To inestigate the e!ect of ethylene concentration on the rate of

ripening fruits.

Apparatus:

• " 1 gallon #iploc clear plastic bags.

• 12 green but mature $full% tomatoes of appro&imately same si'e and

from same species.

• 2 ripe tomatoes

• 2 oer ripe tomatoes

• 1 color chart $showing di!erent ripening stages%

Method:

(i& small hole appro&imately ).*cm in diameter was made at the edges of the 'ip lock bag. Two green tomatoes were placed in each of the + #iploc

bag. ,ne bag was the control and no additional fruit was place in this bag.

n additional ripe tomato was placed in the second #iploc bag and an

additional oerripe tomato was placed in the third #iploc bag. The tomatoes

were obsered oer a *-day period.


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Results / observations

Bags Day 1 Day 2 Day Day !B1 -Two

tomatoes

fully green

-Two

tomatoes

fully green.

,ne tomato

fully green.

The other

tomatoes

green with

break in color

from green to

tarnish yellow

Both tomatoes

light red with hints

of green.

B2 Two

tomatoes

full green

one

tomato at

turning

stage.

2) of the

surface

show a

change in

color to

pink and

the rest of

the tomato

green.

Two tomatoes

fully green

/ one tomato

at turning

stage. ") of

the surface

show a

change in

color to pink

and the rest

of the tomato

green.

Two tomatoes

green with

break in color

from green to

tarnish yellow.

,ne fully red.

Two tomatoes light

red and one fully

red.

B+ two

tomatoes

fully green additional

tomato is

pinkish

red.

Two tomatoes

green with

break in colorfrom green to

tarnish yellow

,ne fully red.

Two tomatoes

green with

break in colorfrom green to

tarnish yellow

,ne fully red.

Two tomatoes fully

red.

,ne tomato red.


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"re#autions0

1. oles were placed in the #iploc bag to allow o&ygen to pass through

which aided in respiration.2. control was used to compare results and aided in the accuracy of the

readingsobserations.

$our#es of error:

1. ll bags were not fully closed.2% 3ot all of the green tomatoes were not fully green or at the same

stage thus some ripened faster than the others.

&imitation:

1% 4ipening of fruits due to other factors such as temperature.


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Dis#ussion0

Ethylene is produced and released by rapidly-growing plant tissues. 5t is

released by the growing tips of roots/ 6owers/ damaged tissue/ and ripening

fruit. The hormone has multiple e!ects on plants. ,ne is fruit ripening.

4ipening is a term applied to fruit that describes the transition from

physiological maturity to senescence $ageing and death of the plant

tissues%. 5t is a deelopmental stage eoled to facilitate reproduction by

preparing the seed-bearing organ for detachment from the plant. 4ipening is

the start of signi7cant biochemical and physiological transformations/ suchas changes in skin color/ internal 6esh softening/ aroma deelopment and

sweetening. 4ipening generally begins after fruit has reached ma&imum si'e

and is physiologically mature.

5n this e&periment tomatoes were place in a plastic bag both ripe and unripe

to speed up the e!ects of the gas ethane produce. ole were placed in the

bags to allow students to obsere the di!erent changes in odor. 5n addition to

that/ ripe tomatoes were place with unripe tomatoes because when fruits are

together/ the ethylene each piece emits prods the others around it to ripen

further/ and ice ersa.

5n bag one only two green tomatoes were place in the #iploc bag and it was

obsered oer the four-day period. ,n obseration only at day three ,ne

tomato fully green while the other tomato was green with break in color from

green to tarnish yellow. 8hile at day 9 both tomatoes light red with hints of

green. The tomatoes in these bag took the longest to start turning and at the

end of the 9-day period although most of the tomato:s surface was red they

weren:t fully ripe as there were hints of green. This happened because there

was a low concentration of ethylene as there was no ripe tomatoes placed in

this bag and as a result the ripening process took longer.

The contents of bag 2 ripened faster than those of bag 1. t day 9/ thetomatoes that were fully green at day one were fully red and the half ripe

fruit was fully red which signaled that it was at the semi-ripened stage.

Because a half ripe tomato was place in this bag the ethane concentration

was greater than in bag 1 and as a result ripening was achieed at a faster

rate.


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4ipening was achieed the fastest in bag +. t the end of the four-day period

all three tomatoes were dark red and fully ripe. This happened because at

day one an oer oerripe tomato was place with two green tomatoes. This

happened because the riper a fruit is/ the more ethylene it produces/ and

thus an oerripe fruit gies o! een more ethylene/ eentually leading to a

concentration of the gas that:s enough to ripen the green tomatoes thatwere tested with it.

The knowledge gained can be instructie in shipping agents of fruits and

egetables as they can use ethylene to fasten up the length at which the

fruits handled ripens and thus increase the cost of distribution also from this

e&periment they can gain knowledge on the perfect time period in which

ethylene should be use and as a conse;uence after the good are remoed

from the shipment ready to be distributed most fruitegetable should be

ripe not oerripe as the speci7c methods and concentration were use when

using ethylene.


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'on#lusion :

5n this lab the hormone ethylene which use as a ripening agent was

inestigated. 8hen the ripe tomatoes were place with unripe tomatoes

because when fruits are together/ the ethylene each piece emits prods the

others around it to ripen further/ and ice ersa. lso it was seen the riper

the fruit that were place with the unripe fruits/ ripening was achieed fasteras the riper a fruit is/ the more ethylene it produces/ and thus an oerripe

fruit gies o! een more ethylene/ eentually leading to a concentration of

the gas that:s enough to ripen the green tomatoes that were tested with it. 5t

is concluded that the higher the ethylene concentration is/ the faster fruit

ripening will be achieed.

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Biology Ethylene