Download Plant Structure and function

NQF Level:
2
US No:
116057
Assessment Guide
Primary Agriculture
Plant Structure
and function
Assessor: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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The availability of this product is due to the financial support of the National
Department of Agriculture and the AgriSETA.
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
2
Unit Standard No: 116057
Before we start…
T
his assessment guide contains all necessary activities
and instructions that will enable the assessor and
learner to gather evidence of the learner’s competence
as required by the unit standard. This guide was
designed to be used by a trained and accredited assessor
whom is registered to assess this specific unit standard
as per the requirements of the AgriSETA ETQA.
Prior to the delivery of the program the facilitator and
assessor must familiarise themselves with content of this
guide, as well as the content of the relevant Learner
Workbook.
Please Note:
This Unit Standard
116057 Assessment
Guide must be read
in conjunction with
the generic Assessor
Guide as prescribed
and published by the
AgriSETA.
The assessor, facilitator and learner must plan the assessment process together, in
order to offer the learner the maximum support, and the opportunity to reflect
competence.
The policies and procedures that are required during the application of this
assessment are available on the website of the AgriSETA and should be strictly
adhered to. The assessor must familiarise him/herself with this document before
proceeding.
This guide provides step-by-step instructions for the assessment process of:
Title:
US No:
Understand the structure and functions of a plant.
116057
NQF Level:
2
Credits:
5
This unit standard is one of the building blocks in the qualification listed below.
Please mark the qualification you are currently assessing, because that will be
determined by the context of application:
Title
ID Number
NQF Level
Credits
National Certificate in Animal Production
48976
2
120
National Certificate in Mixed Farming Systems
48977
2
120
National Certificate in Plant Production
48975
2
120
Please mark the learning program you are
enrolled in:
Are you enrolled in a:
Y
Learnership?
Skills Program?
Short Course?
Version: 01
N
Mark
Note to Assessor:
If you are assessing this
module as part of a full
qualification or learnership,
please ensure that you have
familiarized yourself with the
content of the qualification.
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
1.1
AC 1
NQF Level 2
Unit Standard No: 116057
3
Instructions to learner: Explore and discuss …
Learner Guide: Page 7
Facilitator Guide: Page 12
Take a scale from an onion bulb and use a pair of tweezers to tare off a piece of the
epidermis tissue. Mount it in a drop of water and study it under a microscope. Write
down your observations and discuss it with the rest of the class
Model Answer(s):
This is only to show the student that there are structures/cells in the plant which
cannot be seen with the naked eye, but which play key roles in the growth and
normal function of the plant. The student therefore only have to show the ability
to work with a microscope and observe the cells in the onion membrane.
We can see plant organs with the naked (unaided) eye and we therefore talk
about the external structure of the plant. All these organs are made up of cells
that we cannot see with the naked eye and need a microscope to see these cells.
We therefore talk about the internal structure or the anatomy of the plant.
Cells of the same kind and/or function form tissues like the epidermis, cortex and
vascular tissue. Each tissue has a specific function in the plant organ.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
1.2
SO 1 AC 1-5
NQF Level 2
Unit Standard No: 116057
4
Instructions to learner: Explore…
Learner Guide: Page 9
Facilitator Guide: Page 12
Soak some bean seed and some maize seed in water for 24 hours. Remove the seed
coat and try to find the other parts shown in the diagram.
Seed coat (box)
Cotyledon
Plumule
Axis
Radicle
Endosperm (Food)
Model Answer(s):
Realizing that a seed already contains all the structures which a full grown plant
will have later on. Importance of keeping seed intact to protect this potential
plant.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
2.1
SO 2 AC 1-4
NQF Level 2
Unit Standard No: 116057
5
Instructions to learner: Go outside and explore …
Learner Guide: Page 14
Facilitator Guide: Page 13
Collect 10 weed plants from the garden and describe the root system of each.
Model Answer(s):
Basic knowledge on how the roots look like, the different types of roots and why it
is important also to know what is happening below soil level with the plant.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
3.1
SO 3 AC 1-3
NQF Level 2
Unit Standard No: 116057
6
Instructions to learner: Explore and research …
Learner Guide: Page 18
Facilitator Guide: Page 14
Cut a shoot with leaves from a weed plant, put the cut end in a natural stain
solution and leave it for 24 hours. Make a longitudinal section of the stem and try to
explain what you see.
Model Answer(s):
Basic knowledge on how the stem look like (outside and inside), the different
types of tissue in the stem and the importance/role of each in the functioning of
the plant.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
4. 1
SO 4 AC 1-5
NQF Level 2
Unit Standard No: 116057
7
Instructions to learner: Research and discuss …
Learner Guide : Page 25
Facilitator Guide: Page 15
Write an illustrated essay on the different leaf types and their function as well as
some responses of leaves to the environment.
Model Answer(s):
Basic knowledge on how the leaf look like (outside and inside), the different types
of tissue in the leaf and the importance/role of each in the functioning of the
plant.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
5.1
SO 5 AC 1-4
NQF Level 2
Unit Standard No: 116057
8
Instructions to learner: Explore and discuss
Learner Guide: Page 30
Facilitator Guide: Page 16
Pick any crop, make the following observations and describe and explain your
observations:
•
•
•
•
•
Bud stage of the flowers
Description of flowers
Pollination, stage of flowers when pollinated and pollination agent
Fruit set and stages of fruit development
Seed development
Model Answer(s):
Basic knowledge on how the flower looks like (outside and inside). The different
structures within a flower and what role it plays in pollination and fertilization.
Students will also see from where fruits and seeds develop.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
6.1
SO 6 AC 1-4
NQF Level 2
Unit Standard No: 116057
9
Instructions to learner: Explore and discuss…
Learner Guide: Page 34
Facilitator Guide: Page 17
Collect a variety of fruits dissect the fruits, describe their structure and try to relate
the structure of the parts to specific functions.
Model Answer(s):
Students will learn that not all fruits are the same. Some are dry while others are
fleshy etc. They will also learn that fruit has a specific shape, smell, taste etc. to
facilitate spreading of the seeds.
My Notes …
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
Assessment Feedback Form
Comments / Remarks
Feedback to learner on assessment
Feedback from learner to assessor:
Learner’s Signature:
Assessor’s signature:
Version: 01
Date:
Date:
Version Date: July 2006
10
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
11
S u mma t i v e T e s t a n d At t i t u de &
A t t r i b u t e E v a l u a t i on
B
efore the knowledge test is undertaken, the learner must be reminded of what is
expected from him / her in terms of summative and reflexive competence. Read
and explain to the learner, the Preparation for Your Final Assessment section in
the learner workbook. Learners and assessor should sign off this section to
acknowledge that this step was completed.
Please set up a knowledge test from the questions given as a guideline to learners
and supply each learner with a test sheet.
Supply each report with the following heading:
Unit Standard:
116057
NQF Level:
2
Learner Name:
Questions
1.
Could you see the cells
and other cell
components of the onion
scale epidermis without a
microscope? If not, what
is the reason for not
seeing?
Model Answers
Basic understanding of the size of things and the use of
microscopes to be able to see things which cannot be seen with the
naked eye.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
♦
♦
♦
•
•
2.
Identify the important
parts of a seed and
explain the function of
each.
•
•
NQF Level 2
Unit Standard No: 116057
12
Seed coat – the seed coat derives from the integuments of
the ovule and covers and protects the seed while in a resting
phase (storage).
Endosperm – The endosperm derives from the fertilised
central cell of the embryo sac and contains the energy (food)
for the embryo. In the immature stage, therefore, all seeds
contain endosperm. In some seeds the endosperm is absorbed
by the cotyledons of the developing embryo, so that the
cotyledons become swollen and no endosperm remains in the
mature seed. Such seeds are called ex-endospermous. The
mature seed therefore contains endosperm that is absorbed
only during germination to supply the germinating embryo with
the required energy.
Embryo – the embryo consists of four parts:
Radicle – It is the root apical meristem of the embryo that
gives rise to the primary root.
Plumule – It is the apical meristem (growing point) of the
young embryo that gives rise to the stem and leaves of the
new plant.
Cotyledon(s) – One in monocotyledonous seeds and two in
dicotyledonous seeds, is (are) the first leaf (leaves) of the
embryo produced by the plumule and do(es) contain axillary
buds like any other leaf. They act as haustoria (absorbing)
nutrients from the endosperm. In endospermous seeds
(seeds containing endosperm), the cotyledons become active
during germination and absorb the nutrients from the
endosperm as they are required by the embryo. In exendospermous seeds, (seeds without endosperm), the
endosperm is absorbed by the cotyledons before the seed
matures and the nutrients are, therefore stored inside the
swollen cotyledons.
Axis – the part of the embryo connecting the plumule and the
radicle. In seeds with epigeal germination (cotyledons
appear above the ground), the axis elongates to push the
cotyledons above ground and that part of the axis below the
cotyledons is then called the hypocotyls. In seeds with
hypogeal germination, the axis does not elongate during
germination and the cotyledons therefore remain
underground.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
3.
Identify the different
parts of a maize seed. Is
this a monocotyledonous
or dicotyledonous seed?
NQF Level 2
Unit Standard No: 116057
13
Different monocotyledonous seedlings showing the cotyledon (c)
imbedded in the endosperm, some elongated to push the plumule
into the soil, and (sp) the first leaf covered by a sheath. 1 – Palm
(Phoenix), 2 – longitudinal section of 1 to show the sheath and
plumule at the base, 3 – Maize, 4 – section of 3, 5 – Wheat.
Monocotyledonous seeds contain only one cotyledon and the
plumule is situated on the side of the embryo axis. In
monocotyledonous plants the leaf base is a sheath covering a part
of the stem above the node. In the seedling the first leaf above the
cotyledon is usually reduced to the sheath only.
4.
Identify the different
parts of a bean seed. Is
this a monocotyledonous
or dicotyledonous seed?
Different dicotyledonous seedlings showing the cotyledons (c) and
the first leave produced by the plumule between the cotyledons. 1Lupin, 2 - Vetch, 3 - Plantago, 4 – Escholzia, 5 – Geranium, 6 –
Eranthis.
In dicotyledonous seeds there are two cotyledons and the plumule
is situated between the two cotyledons.
5.
Explain the function of
plant roots.
The function of roots are a) for anchoring the plant to the substrate
(soil) and b) for the absorption of water and nutrients dissolved in
the soil water. The absorption function is carries out by the young
epidermis cells, of which some may grow out to form root hairs.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
14
The different root systems:
• The tap root system – the tap root derives from the radicle
and produces lateral roots of different orders (First order,
second order etc.. In dicotyledonous plants the tap root can
usually has the same life span as the plant A tap root system
can therefore develop only from seedlings.
• Adventitious root system - in monocotyledonous plants
the tap root functions during the seedling stage, but may
thereafter stop growing and adventitious roots develop from
the base of the stem, forming an adventitious root system. In
grasses and some other plants the adventitious roots are
fibrous. They are thin and hair-like and usually contain more
fibres than other roots. The whole root system is then called
a fibrous root system The feeding roots of many other
plants, however, can also be hair-like and fibrous even if they
form part of a taproot system. And are often called hair
roots.
6.
Do all plant species have
the same type of root
system? If not, give
examples of the different
types of root system.
7.
Have you ever eaten a
plant root? If yes, from
which plant and what
type of root was it?
Basic application of embedded knowledge.
Exp. Carrot – tap root.
How is it possible for
water, taken up by the
roots, to end up in the
leaf? Explain.
Almost all the water the plant takes up from the soil enters through
the youngest part of the root where the root hairs develop a few
millimetres behind the root tip. Absorption takes place directly
through the epidermis and root hairs that provide an enormous area
of absorption. The walls of the root cells are made up of cellulose
fibrils (threads). The open spaces between the fibrils are filled with
water which means that water can move through the cell walls from
one cell to the other and this movement is called apoplastic
movement of water. Water can therefore move from the soil water
into the cell walls of the root hairs, through the cell walls of the
cortex up to the endodermis where the water is blocked by the
casparian strips in the endodermis. The water is then forced through
the cytoplasm of the endodermis cells, the pericycle and then into
the xylem vessels that takes the water through the root and stem
into the leaves. Water can also be absorbed by the root hairs
through the process of osmoses (water molecules moving from an
area of high concentration – in the soil water - to an area of low
concentration – inside the root hair). The water then moves from
the root hairs symplastically through the cytoplasm of the root
tissues to the endodermis.
8.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
9.
How does gravity affect
the growth of roots and
stems?
♦
Do all plant species have
the same type of stem? If
not, describe the different
stem types and name one
plant species having such
a stem.
♦
♦
♦
♦
♦
11.
12.
Unit Standard No: 116057
15
Gravity is a force that pulls everything towards the earth and –
tropism is a turning into the direction from where a stimulus comes.
The growth of most roots is positively gravitropic which means
that they grow towards the direction of the pull of the earth. This
phenomenon can be illustrated by planting maize seeds with the
sharp end (radicle) of the seed pointing upwards. During
germination the root will turn around and grow downwards. Stems
on the other hand tend to grow negatively gravitropic, meaning
that they grow away from the stimulus coming from the pull of the
earth.
♦
10.
NQF Level 2
Herbaceous stems – stems of most monocotyledonous plants
with no secondary growth. Or stems of most annual
dicotyledonous plants with very limited secondary thickening
growth.
Woody stems – stems of dicotyledonous plants and
gymnosperms with the extensive secondary thickening growth.
A source for commercial wood.
Stems of vines– long, slender stems that con not support
themselves and use other plants or structures to support them
like that of runner beans.
Tuber – a fleshy, terminal end of an underground stem that
can be used for propagation like that of the potato. Some can
also be used as food.
Rhizome – a swollen underground with distinct nodes and
internodes, often with sympodial growth like in Iris and kikuju
grass. Can be used for propagation.
Corm – a swollen stem base like that of Gladiolus. Can be used
for propagation.
Bulb – a reduced stem with succulent leaf bases covering the
growing point like that of onion. Can be used as food and for
propagation.
Describe the function of
the stem in giving the
plant structure.
Stems form the framework of the plant, exposing the leaves to the
maximum available sunlight. A good example is vines that are often
found in forests. They do not spend extra energy to develop strong
stems, but rather use other supports to grow out of the forest
canopy as quickly as possible to expose their leaves to the sun.
Explain the movement of
nutrients and
carbohydrates in the
stem.
Stems contain vascular tissue like the vessels and tracheids of the
xylem that transport water and inorganic solutes (dissolved
minerals) from the roots to other plant organs like leaves, flower
and fruit. The sieve tubes and sieve cells of the phloem are
transporting organic products from the leaves to other plant organs
like stem growing points, flowers, fruit, seed and roots where it is
utilised for energy or stored as reserve food.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
Lamina
13.
16
Pinnae
Make use of a simple line
drawing to show the
different parts of a simple
and compounded leaf.
Petiole
Simple leaf
14.
Are all leaves of all plant
species the same? What
functions do the different
leaves have?
Compound leaf
All leaves originate from a stem apical meristem or apical dome as
small protuberances called leaf primordia, but during their further
development and maturation leaves can take on different forms,
shapes and sizes depending on the specific function they have to
perform.
“Ordinary” or “typical” photosynthetic leaves have green,
flattened laminas (leaf blade) and their main function is
photosynthesise. These leaves can be simple with an undivided
lamina or compound with a subdivided lamina
♦ Bracts – Bracts or scales are leaves that matured in their
primordial (baby) form and are mostly colourless or brown.
Their main function is to protect buds like flower buds in the
young inflorescence, apical buds and axillary buds.
♦ Tendrils - parts of the leaf in some vines are transformed into
thin tendrils that curl around support structures to help the
plant in its climbing habit like in the sweet pea (Lathyrus
odoratus) and Bignonia.
♦ Succulent leaves – the leaves of some plants are adapted to
store water like the leaves of aloes or they can store food like
bulb scales and cotyledons of the bean seed. Cotyledons have
an additional function by acting as haustoria, extracting
nutrients from the endosperm.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
17
For the manufacturing of food (carbohydrates), the leaf needs:
•
•
•
•
Chlorophyll - found in the chloroplasts of the palisade (Pal)
and spongy parenchyma cells (SP) of the leaf.
Sunlight – leaves to be exposed to light – the light passes
through the colourless upper epidermis (UE) and is absorbed
by the chlorophyll.
Water – supplied by the xylem elements in the vascular
bundle (VB).
Carbon dioxide (CO2) – passing through the stomata (St)
from the atmosphere into the open spaces between the cells
inside the leaf.
The process:
♦
15.
How do plants get
carbohydrates? What
important role does
sunlight play in this
process?
♦
Step 1 dependant on light)
Energy from the sunlight is converted to chemical energy by
the chlorophyll.
• The energy is used to split water into hydrogen (H2) and
oxygen (O2). The released oxygen leaves the leaf through the
stomata into the atmosphere.
•
•
Step 2- not dependant on light, but influenced by temperature)
In another process, which is temperature sensitive, the
hydrogen is bound to the carbon dioxide to form a
carbohydrate
The formula
6CO2 + 12H2O
light
C6H12O6 + 6O2 + 6H2O
The carbohydrates (sugar) is then ‘loaded’ into the phloem in the
vascular bundle and transported to the different parts of the plant.
Chloroplasts can only develop from proplastids (young plastids)
present in dividing cells. Each chloroplast is surrounded by a double
membrane The internal structure of the chloroplast is rather
complex and can only become fully developed if the cell is exposed
to sufficient light. In flowering plants the chloroplasts are usually
disk-shaped and measure 4 to 6 micrometers in diameter
(1micrometer (µm) = 0.001 mm). The ground substance of the
chloroplast inside the double membrane is called the stroma and
the stroma is traversed by an elaborate system of membranes in
the form of flattened sacs called thylakoids, packed in stacks like
coins, called grana (singular granum). The grana are
interconnected by a similar double membrane system as the
thylakoids. The chlorophyll is contained in the thylakoids of the
grana and in the absence of light the grana becomes disorganised
and the chlorophyll breaks up
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Understand the structure and functions of a plant
Primary Agriculture
16.
Can plant leaves react to
environmental
conditions/stress
conditions? If yes, explain
how.
NQF Level 2
Unit Standard No: 116057
18
♦
Etiolation – in the absence of light or greatly reduced light,
leaves become yellow due to the breaking down if the
chlorophyll and the thylakoids in the chloroplasts and we say
the leaves are etiolated. The green colour will however return if
the plants are returned to light conditions.
♦
Leaves sensitive to touch – The pinnae of Mimosa pudica
leaves will close when they are touched. Leaves of the
insectivorous Venus Fly Trap contain sensitive hairs and when
these hairs are touched by an insect, the two halves of the leaf
close quickly to catch the insect Leaf tendrils of plants like the
sweet pea will turn around a support as they make contact.
♦
Flowering response – Some plants are sensitive to the number
of dark hours in the daily 24-hour cycle. Some plant, called
short day plants like chrysanthemum, will flower as soon as
the nights become longer than the critical 16 hours. When
planted outside, they usually flower in autumn. Long day
plants on the other hand, will flower if the nights become
shorter than16 hours. Day neural plants are not sensitive to
day length.
♦
Heat– Stomata on leaves usually close when the maximum
temperature rises above a certain value, meaning that
photosynthesis will also stop.
Stigma
Style
17.
Make a simple line drawing
to show the different parts
of a flower.
Recepticle
Pedicel
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
19
Pedicel – an elongated internode attaching the flower to the stem
Recepticle - a set of very closely spaced nodes bearing the whorls
of modified leaves (flower parts).
Calyx – the first whorl of flower leaves (sepals)protecting the other
18.
After identifying the different
parts of a flower, give the
function(s) of these parts.
leaf whorls during the development of the flower up to the bud
stage.
Corolla – the second whorl of modified leaves, (petals)usually
brightly coloured to attract pollinators to visit the flower.
Stamens - one or two whorls of highly modified leaves forming the
stamens consisting of the filament (petiole) and the anther (lamina)
producing the pollen.
Pistil – composed of one or more separate or fused carpels
(leaves). The terminal parts of the leaves form the stigma that
receives the pollen during pollination. The extended central parts of
the leaves form the style while the basal parts of the leaves form
the ovary carrying the ovules. In most flowers the carpel leaves are
sessile (with no petiole), but in some flowers like those f the
Capparidaceae, the petioles form the gynophores.
The one or more whorls of anthers of the same flower is referred to
as the androecium which forms the male part of the flower
producing the pollen (the term gynophore above, therefore means
the carrier (-phore) of the gynoecium.
One or more carples of the same flower is referred to as the
gynoecium, forming the female part of the flower and contain the
ovules. After pollination and fertilisation, the stigma and style
withers and die while the ovary gives rise to the fruit. The fertilised
ovules inside the fruit give rise to the seeds.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
19.
Explain the role of the
female parts of the
flower in fruit and seed
production.
NQF Level 2
Unit Standard No: 116057
20
As mentioned above, the pistil, consisting of the stigma. style and
ovary, is the female par of the flower. The function of the stigma is
to receive the pollen during pollination. If recognised by the stigma,
the pollen grain wil germinate and produce a pollen tube that grows
down the style in the direction of the ovary The pollen tube carries
the two sperm cells derived from the generative cell in the pollen
grain. On reaching the ovary, the pollen tube grows to an ovule,
enters the ovule through the micropyle, penetrates the embryo sac
and sheds the two sperm cells inside the embryo sac from there one
will fertilise the egg cell (the nuclei of the two cells fuse) and the
other one fuses with the two nuclei of the central cell of the embryo
sac (Double fertilisation) The fertilised egg then develops into an
embryo (the baby) of the seed, the fertilised central cell produce the
endosperm (food) and the integuments of the ovule forms the seed
coat (the box). The whole ovule, therefore gives rise to the seed.
The developing seed produces hormones that stimulate the ovary
wall to develop into the wall of the fruit (pericarp).
The whole ovary therefore develops into the fruit, provided the
ovules develop into seeds. There are however exceptions where the
fruit will develop without fertilisation and seed formation as in the
case of the banana and pineapple. This process is called
parthenocarpy and the fruits are called pathenocarpic fruit.
Pathenocarpic fruit (seedless fruit) can also be artificially produced
by spraying flowers with hormones like auxin (seedless tomatoes) of
gibberllic acid (seedless grapes).
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
21
Mature fruit are classified in different categories based on the
structure of the fruit wall. Different parts of the flower can,
however, also take part in determining the fruit structure.
6.1
20. There are different types
of fruits available. Say
what type of fruit the
following are and explain
why you think it is that
specific type of fruit.
Peach, pumpkin, tomato,
soybean, strawberry, fig.
Simple fruit –fruit developing from a single ovary from a
single flower.
Single, fleshy fruit – the pericarp is soft and fleshy.
• Drupe or stone fruit. – like peach and mango. The
pericarp can be divided into exocarp,(the peel of the peach
and mango) mesocarp (the soft edible part) and the
endocarp, ( hard, stone-like or leather-like layer
surrounding the seed).
• Berry – also a fleshy fruit, but the mesocarp and endocarp
are both fleshy and not distinguishable from each other as
in the grape berry, tomatoes, papayas, avocado, coffee,
blueberries, gooseberries, and many others.
• Pepo – the fruit of the cucurbit family like pumpkins,
cucumber and watermaelon are actually also berries, but
the carpels are imbedded in the concave receptacle
(hypogynous or inferior ovary) that takes part in the
formation of the fruit wall.
• Pome – like the pepo the fruit also derives from an inferior
ovary with the receptacle taking part in the formation of
the fleshy fruit wall, but it also has a firm, partly woody
endocarp surrounding the seeds.
Single dry fruit - in dry fruits the pericarp in the mature fruit
is a dry, leathery or papery structure and the three layers are
not distinguishable.
• Nut – an indehiscent (not opening) fruit consisting of a single
carpel as in the nuts falling from oak trees.
• Achene –an indehiscent fruit consisting of two carpels as in
the sunflower fruit (mostly called a seed).
• Capsule –a single, dry dehiscent fruit, usually consisting of
more the one carpel and as the classification indicates, the
mature fruit dehisces (opens by itself) and the seeds are
distributed as in the case of the Strelitzia fruit depicted in the
figure above. Capsules are also found in Datura and fruit of
orchids.
• Pod or legume – a dehiscent fruit, but consists on one carpel
only as in the case of a pea pod, a bean, soybean most of the
acacias.
6.2 Aggregate fruit –Derive from a single flower but is made up
of a number of separate ovaries on the same receptacle like
the fruit of the strawberry consisting of an aggregation of
small drupelets.
6.3
Multiple fruit – A collection of fruit on a common
inflorescence axis as in the syconium of the fig where a great
number of achenes deriving from minute flowers are collected
in a concave , fleshy inflorescence axis. In the malberry
(Morus) and the pineapple,(Ananas) a collection of fleshy fruit
and flower parts are collected on a common axis.
Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
NQF Level 2
Unit Standard No: 116057
22
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Version: 01
Version Date: July 2006
Understand the structure and functions of a plant
Primary Agriculture
Version: 01
NQF Level 2
Version Date: July 2006
Unit Standard No: 116057
23