Recognise Plants, Topic 3, Plant Morphology. Part 3: Fruits

Question 1

The broad categories of fruits are:

Answer 1

Fleshy indehiscent (fruits which have obviously fleshy pulp and do not split open. They are
 usually eaten by omnivores or herbivores and then the seeds are expelled).

Dry dehiscent fruit (Non-fleshy fruits that mature and then split open to release the seeds).

Dry indehiscent fruit (Non-fleshy fruits that do not split open but still germinate).

Question 2

Define Dehiscence

Answer 2

The splitting or opening up of a pod or fruit.

Question 3

In addition, all fruits, whichever of the above categories they are in, will also fall into a further three categories which are:

Answer 3

• Simple – formed from one ovary and may contain one or many seeds
• Aggregate – formed from a single flower and the fusion of ovaries which were separate within the flower (e.g. Raspberries and Blackberries, as well as, Strawberries).
• Multiple – one overall fruit formed from the fused ovaries of multiple flowers! A good example is Pineapple.

Question 4

Fruit is the result of the _________ of the ______ from _______ contained in the pollen grains

Answer 4

fertilisation, ovules, sperm

Question 5

Two plants that where the flower parts remain after fertilisation has occurred

Answer 5

Ochna Serrulata, Ceratopetalum apetalum (Christmas Bush)

Question 6

Ferns produce _______ inside a _______.

Answer 6

Spore, sporangium

Question 7

List two types of Gymnosperms

Answer 7

Cycads, Confiers

Question 8

Conifers produce cones or _______

Answer 8

strobilus

Question 9

Pericarp

Answer 9

fleshy part of the fruit which is often eaten

Question 10

Epicarp or exocarp

Answer 10

the outermost skin which can be tough and inedible (rind of a lemon.)

Question 11

Endocarp

Answer 11

innermost layer. may be edible or not.

Question 12

Berry

Answer 12

The term berry is defined botanically as a fleshy fruit with one or more seeds with the seeds embedded in the fleshy tissue of the pericarp. The ‘berries’ that botanically meet this definition are fruits such as blueberries and cranberries.

Question 13

Hesperidium

Answer 13

Citrus fruits which have a thick rind and ar divided into obvious segments

Question 14

Pepo

Answer 14

Cucumbers, zucchini and watermelons, etc. which have a hard outer skin but no septae or compartments.

Question 15

Drupe (simple)

Answer 15

Drupes are single fleshy fruits produced usually from a single seeded ovary with a hard woody layer. They have a very thin
exocarp, surrounding a thick fleshy mesocarp, which surrounds a hard woody endocarp. The seed lies inside the endocarp.

Stone fruit

Question 16

Native Genera with berries include

Answer 16

Dianella, Breynia, Acmena/Syzygium and Cissus.

Question 17

Drupe

Answer 17

Persoonia, Elaeocarpus, Davidsonia and Monotoca

Question 18

Pome

Answer 18

A pome covers a range of fruits formed by some plants in the Rosaceae family with the best examples being apples (Malus sp. – pictured left) The outer flesh of a pome is thought to be derived from different parts of the flowering carpels, rather than a thickening of the ovary wall itself. The ‘core’ of the apple is the endocarp which is somewhat woody. At the base of an apple, we can see the shrivelled remains of the
calyx, stamens and styles.

Question 19

Aggregate Fruits

Answer 19

Aggregate fruits are formed from a single flower with many ovaries. Examples are
Strawberries, Blackberries and Raspberries – but even these are different to each other. Strawberries consist of flesh that is derived from the receptacle rather than the ovary
wall. Each seed in an achene – a type of dry indehiscent fruit (covered below) – and is on the outside of the fruit! (clearly visible when we look at a strawberry).

The achenes are produced by the ovaries and house a seed inside.

Blackberries and Raspberries (Rubus spp. – pictured left) are aggregate fruits consisting of a cluster of small drupelets (a term used when drupes are produced in a cluster). Each drupelet is developed from an ovary and house a seed.

Question 20

Multiple Fruits

Answer 20

multiple fruits are formed from the ovareis of multiple flowers. Each flower of the plant produces a fruit but, but then, the fruits mould together to farm a large mass! Examples are pineapples, figs, mulberries and breadfruit.

Question 21

Synconium

Answer 21

a term for Figs. The inflorescence of a fig is invaginated (opens inside rather than outside the receptacle, with all the flowers hidden on the inside of the receptacle which is hollow!

The flowers are pollinated by insects which squeeze inside the receptacle. Each flower is pollinated and then small tiny fruits are produced called achenes. However, they are all contained inside the one fleshy fruit called a synconium.

Question 22

List the Fleshy Fruit categories

Answer 22

Berry, Drupe, Aggregate fruits, Mulitple fruits,

Question 23

List examples of dry fruits–dehiscent

Answer 23

Pod, Follicles, Capsule, Silique, Schizocarp

Question 24

Pod

Answer 24

Fabaceae. Pods are sometimes loosely referred to as peas, beans or legumes. A pod is what we know as a bean or pea pod. They are typically long and narrow and split down two sides to release the seeds. Seeds may be few or numerous (say up to 15 or so in each pod).

Pods are mainly associated with the Fabaceae family which includes many Australian genera such as Acacia, Pultenaea, Daviesia and
Hardenbergia. Faboideae have pods which come in a wide variety of shapes and sizes and can hardly look like pods at all. Examples are the genera Daviesia and Pultenaea.

Wattles (Acacia spp.) are one of the best groups to look at to get familiar with pods as are snow
peas, beans and Senna spp.

A pod of the native Bossiaea heterophylla is pictured left.

Question 25

Follicles

Answer 25

Follicles are typically hard woody fruits that split down one side of the wall first and then a second side later. Usually they only contain one or two seeds. One of the most prominent examples is the Proteaceae family with genera such as Banksia, Grevillea, Hakea (pictured left) and Telopea (Waratah) all producing follicles. In Banksia, we saw how the individual flowers are clustered together in a spike. Therefore, the follicles are clustered together in a cone-like structure. But they should not be referred to as a cone. Additionally – the genus Macadamia, in the Proteaceae, are said to produce ‘nuts’ (which is an indehiscent fruit). Follicles are typically hard woody fruits that split down one side of the wall first and then a second side later. Usually they only contain one or two seeds. One of the most prominent examples is the Proteaceae family with genera such as Banksia, Grevillea, Hakea (pictured left) and Telopea (Waratah) all producing follicles. In Banksia, we saw how the individual flowers are clustered together in a spike. Therefore, the follicles are clustered together in a cone-like structure. But they should not be referred to as a cone.

Question 26

Fleshy indehiscent fruit

Answer 26

fruits which have obviously fleshy pulp and do not split open. They are usually eaten by omnivores or herbivores and then the seeds are expelled.

Question 27

Dry dehiscent fruit

Answer 27

non fleshy fruits that mature and then split open to release the seeds.

Question 28

Dry indehiscent fruit

Answer 28

non fleshy fruits that mature and then split open to release the seeds.