Roots, Stems, Leaves, Flowers, and Seeds. Mrs. Chandrashekhar
Biology M4 Flowers to fruits and seeds
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Transcript of Biology M4 Flowers to fruits and seeds
http://en.wikipedia.org/wiki/File:Nectarine_Fruit_Development.jpg
From Flowers to Fruits Module 4 Unit 13 Lesson 3
How did that happen? Let’s find out! 1
Introduction
Young buds can be observed which must have grown into new flowering shoots.
Some flowers are fully developed and more than likely some were already pollinated. Successful pollination and also fertilization has obviously occurred as ripened fruit are present observed.
The plant has taken another journey from flowers to fruits!
2
Objectives
When you finish this section, you should be able to:
1. describe the structure of a ‘typical’ simple fruit.
2. relate the structure of selected fruits to the structure of the flowers from which they were formed.
3
Fruit or Vegetable?
4
When you eat each of these vegetables, what part of a plant are you really eating?
http://urbanext.illinois.edu/gpe/case1/c1facts2e.html
www.tntisland.com/fruits.html
CHECKCHECK
FEEDBACK
Did you know that they are ALL ‘ripened’ ovaries and are really the products of fertilization? They are fruits.
So, when you eat those vegetables shown, you’re
really eating what was once the ovary!
http://en.wikipedia.org/wiki/Fruit 5
How is a fruit formed?
Remind yourself of what happens during fertilization by clicking open this link>> http://www.emunix.emich.edu/~ghannan/systbot/doublefertanimation.html
Stamen
Stigma
Ovary
Pea flowerOvule
Seed
Pea fruit
Simple fruit
6
As a fruit forms…
…. sepals, petals, stamens wither and usually fall off. (Sometimes sepals may remain attached to the fruit.) Look at the sepals
that remain on the
Rose hips.
7
As a fruit forms…. …. its weight might cause it to hang in an upside
down position in relation to the flower from which it formed.
Its wall can
dry out.
http://en.wikipedia.org/wiki/File:Fruit_I_IMG_8692.jpg
http://toptropicals.com/pics/garden/c21/0665.jpg 8
Barbados Pride
Poinciana fruits
What is a fruit?
A fruit is the packaging for seeds!
• It is an ovary in which further development of the fertilized ovule/s has taken place, resulting
in seed formation.
• A fruit has a fruit wall or pericarp,
a placenta to which each seed is attached by a stem called the funicle.
9
What is a Fruit?
• Each fruit has two scars – one where the style was attached to the ovary, the other on the opposite side, where it was attached by the pedicel to the plant.
• The two functions of a fruit are:1. to protect the seed/s and
2. to aid in seed dispersal.
A fruit is a guarantee of the next generation because it contains the seed with an embryo plant in it.
10
exocarp or skinThe seed is protected inside the hard endocarp
The Parts of a fruit and its seed
http://waynesword.palomar.edu/termfr4.htm
scar of pedicel
scar of the style
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The Parts of a fruit and its seed
The pericarp is different from the seed coat or testa.
http://en.wikipedia.org/wiki/File:Drupe_fruit_diagram-en.svg
12
http://en.wikipedia.org/wiki/File:Illustration_Punica_granatum2.jpg
Pomegranate – Look at this diagram (Top left)
and photo (Top Right) of a flower.
Ovary withovules
Stamens
Pistil
Here are photos of the whole fruit and one cut open (Right).
Sepal
http://waynesword.palomar.edu/ecoph20.htm13
Activity
Label three parts of the fruit and explain from which part of a Pomegranate flower each part grew.
CHECKCHECK 14
FEEDBACK Click open this website, scroll down to see photos
of pomegrante fruit: http://waynesword.palomar.edu/termfr4.htm
.
fruit wall comprising
leathery exocarp, mesocarp = ovary
wall and receptacle
scar = remains of pedicel
seeds = fertilized ovules
persistent sepals (with stamen cluster inside)
Pomegranate fruit formed from an inferior ovary
15
Why aren’t all fruits exactly alike?
Well…. that depends on the flowers from which they form, and how they formed after fertilization!
Depending on the structure of the flower, fruits develop with different structures which enables us to put them into one of several groups.
16
How fruits develop: 1. Simple Fruit
1. Simple fruit - develop from one carpel from a single, separate flower and can be:
• Dry (Visit: http://www.backyardnature.net/frt_simp.htm )
• Fleshy (Visit: http://www.backyardnature.net/frt_flsh.htm )
• Accessory
e.g. peas/ other pods,
tomatoes, oranges,
capsules, grains, plums,
mangoes. Click open and read from the above websites.
17
http://www.backyardnature.net/frt_3grp.htm
Simple fruits
The fruit wall may dry out as the fruit develops from the ovary.
L – R: Peanut, Tamarind are Simple Fruits
18http://waynesword.palomar.edu/termfr1.htm#baobab
Simple fruit- Sunflower
• Forms small, one-seeded simple fruits with dried-out pericarps.
• The three pericarp layers are not distinguishable.
19
http://jbworld.jbs.st-louis.mo.us/science/resources/flower/fruit3.html
Simple fruit - Orange
20
http://visual.merriam-webster.com/plants-gardening/plants/fruits/fleshy-fruit-citrus-fruit.php
The middle layer of the pericarp often becomes fleshy with stored food. The outer layer often changes colour when ripe.
Simple fruit - CucumberFemale flower will develop into the fruit after fertilization.
Prickly inferior ovary, which is the future cucumber
http://www.backyardnature.net/fl_def.htm
21
How fruits develop: 2. Compound Fruit
2. Compound fruit - develops from several ovaries in either a single or multiple flower/s. Includes:
• Aggregate fruits - has many small fruits each with a seed; develops from different ovaries of a single flower e.g. Strawberry
• Multiple fruits – with fruits of separate flowers merged or packed closely together e.g. Pineapple, Jackfruit, Breadfruit.
22
As a fruit forms…
The single flower has
several pistils that
mature together and
stick/aggregate together
as a clustered unit on a
single receptacle, forming
an Aggregate fruit.
It has seeds from different ovaries of the single flowers.
23
flowerhttp://www.backyardnature.net/frt_3grp.htm
Aggregate fruit
Stamen
Stigma
Ovary
Raspberry flower
Stamen
Carpels
Carpel(fruitlet)
Raspberry fruit
Aggregate fruit
Raspberry
http://visual.merriam-webster.com/plants-gardening/plants/fruits/fleshy-fruit-berry-fruit_2.php
24
How fruits develop
Soursop is a large, fleshy, berrylike Aggregate fruit. It is formed by the aggregation of ripened ovaries + the fleshy receptacle.
Click open this link. Read to see how Soursop and paw-paw fruits relate to the flowers from which they were formed:http://www.biology-resources.com/plants-fruit-tropical.html
25http://www.fotosearch.com/photos-images/pawpaw.html
Activity
On the next slides, look at the Soursop and Strawberry diagrams, then examine actual samples.Check for paw=paw at http://www.biology-resources.com/documents/plant-fruit-tropical-2.doc
26
Accessory fruit forms…
…. some or all of the fleshy, usually edible, part might not be formed from the ovary, but instead is derived from the receptacle that holds the ovaries or from some other adjacent tissue e.g. receptacle, producing an Accessory fruit. Click open, scroll down and read about the (American) Apple and Strawberry at these websites. •http://www.biology-resources.com/documents/plant-fruit-3.doc
•http://waynesword.palomar.edu/termfr4.htm
Cut open and examine samples of the fruits.
27
Skin
Receptacle Ovary /real fruit
wall
American Apple – an Accessory fruit
28
Strawberry Flower
http://en.wikipedia.org/wiki/File:Longitudinal_section_of_raspberry_flower.gif
http://www.countrysideinfo.co.uk/flower.htm
Gynoecium = many free simple carpels
29
Close-up of the surfaceof a young strawberry shows simple fruits each with style and stigma.
http://en.wikipedia.org/wiki/Strawberry
The receptacle and flower stalk form part of the Strawberry fruit wall.
30
This accessory “fruit"
is actually an enlarged
receptacle.
http://waynesword.palomar.edu/termfr4.htm
http://visual.merriam-webster.com/plants-gardening/plants/fruits/fleshy-fruit-berry-fruit_3.php
“seed” is really a simple fruit
Strawberry = Aggregate-accessory fruit
31
As a fruit forms…
…a Multiple Fruit may develop. Each fruit forms when a cluster of separate flowers (each with its own pistil) that are grouped together on the same inflorescence have their fertilized ovules mature together to form one fruit.
32
Pineapple flowers (Diagram, left; photo, right)
Pineapple inflorescence
Multiple fruit
Flower
Eachsegmentdevelopsfrom the carpelof oneflower
Pineapple fruit
http://upload.wikimedia.org/wikipedia/commons/c/cb/Pineapple_and_cross_section.jpg
Click open http://jbworld.jbs.st-louis.mo.us/science/resources/flower/fruit5.html and read the information presented.
Young pineapple inflorescence. Each unit is a flower.
33
Pineapple = Multiple fruit
Pineapple inflorescence
Multiple fruit
Flower
Eachsegmentdevelopsfrom the carpelof oneflower
Pineapple fruit
http://www.botany.hawaii.edu/faculty/webb/BOT201/Angiosperm/FlowerFruit.htm
Central axis is the receptacle
34
Jackfruit - is a Multiple fruit; it is formed from the fusion of ovaries from many individual flowers plus the fleshy stem axis.
single carpel of a single flower
seeds and pericarp
35
Breadfruit- a Compound False Fruit
• Male and female flowers grow on thesame breadfruit tree.(Only female flowers form fruits.)
• The hexagon-like disks visible on theskin are flowers that became fruits.
www.nairaland.com/nigeria/topic-359719.0.html
http://en.wikipedia.org/wiki/Breadfruit
36
Breadfruit - this compound, false fruit develops from the swollen perianth of over 1,500 female flowers growing on a fleshy receptacle.
http://en.wikipedia.org/wiki/Breadfruit 37
Cashew Apple – a false fruit The fleshy Cashew ‘apple’ is the swollen
succulent stalk/pedicel and base. The ‘nut’ is a dry fruit with one seed. Both parts store food.
www.fao.org/.../vlibrary/ac306e/ac306e04.htm slog.thestranger.com/2008/04/new_fruit 38
Summary
Fruits differ from each other because…
1. the flower structures were different especially the pistil structure and the number and position of fertilized ovules that became the seeds.
2. the position of the ovary in respect to other floral whorls and also the sepals, petals stamens may/may not be retained as the fruit forms.
39
Summary
Fruits differ from each other because…
3. parts such as the receptacle or flower stalk may become incorporated in the fruit wall.
4. the ovary (fruit) wall changes in different ways e.g. becoming dry/fleshy, coloured, hairy etc.
The next slide gives a summary diagram of thecycle of development from formation of the zygoteto fruit.
40
Summaryhttp://leavingbio.net/The%20Structure%20Functions%20of%20Flowers_files/image031.jpg
41