1.Flowers, Fruit and Seeds Flashcards
(38 cards)
1
Q
3.11 State the function of flowers
A
- Aid pollination and reproduction
2
Q
3.12 Label these key parts of a monocotyledon flower:
- receptacle,
- tepal,
- sepal,
- petal,
- calyx,
- corolla,
- nectary,
- anther,
- filament,
- stamen,
- stigma,
- style,
- ovary,
- ovule
- Perianth
A
3
Q
3.12a Describe the structure and the function of Perianth
A
- Collective term for calyx and corolla (sepals and petals)
- Easy to see on Diocots - sepals are clearly distinct - often visable from behind
- Harder to see on Monocots - nearly indistinguishable
4
Q
3.12a Describe the structure and the function of receptacle
A
- Thickened part at the end of the flower stalk on which the organs of a flower grow
- Holds all the floral parts together
- May keep the flower in an elevated position to attract pollinating insects
5
Q
3.12b Describe the structure of tepal
A
- Describes the sepal or petal when the two can not be easily told apart
6
Q
3.12c Describe the structure and the function of sepal
A
- A single part of the outermost whorl, the calyx, usually green
- Protect the the unopened developing flower
7
Q
3.12d Describe the structure and state the function of petal
A
- Single unit of the corolla, or second floral whorl
- Often brightly coloured
- Attract pollinating insects thereby increasing the chance of pollination
8
Q
3.12e Describe the structure and the function of calyx
A
- Collective term for sepals
- Protects the developing flower
9
Q
3.12f Describe the structure and the function of corolla
A
- Collective term for petals
- Attract pollinating insects thereby increasing the chance of pollination
10
Q
3.12g Describe the structure and the function of nectary
A
- Organ in which nectar is formed and stored
- Produce nectar which attracts pollinating insects thereby increasing the chance of pollination
11
Q
3.12h Describe the structure and the function of anther
A
- Part of the stamen containing the pollen
- Produce male sex cells needed for reproduction
12
Q
3.12i Describe the structure and the function of filament
A
- Slender stalk that attaches to the base of the flower
- Supports the anther
13
Q
3.12j Describe the structure and state the function of stamen
A
- Combination of the filament and anther
- Produce the pollen grains which house the male sex cells
14
Q
3.12k Describe the structure and the function of stigma
A
- Often sticky
- Adapted to catch and trap pollen
- Receives pollen on the female organ of a flower
15
Q
3.12l Describe the structure and the function of style
A
- Part of the female organ
- Between the ovary and the stigma
- Often long and slender
- Assists pollination by transporting pollen grains to the egg
16
Q
3.12m Describe the structure and the function of ovary
A
- Ovule-bearing part of the female organ
- Often enlarged
- Contains and produces ovules which may eventually become the fruit
17
Q
3.12n Describe the structure and the function of ovule
A
- Immature seed in the ovary before fertilization
- Produce female sex cells (eggs) needed for sexual reproduction
18
Q
3.13 State the meaning of ‘monoecious’ and dioecious’ in relation to plants.
State 2 examples of each
A
Monoecious
- Plants with male and females flowers on the same plant
- Or a plant where all flowers produce both functional male and female organs
- Described as hermaphrodite
- Majority of plants
- e.g. Cedrus atlantica
- e.g. Quercus robur
Dioecious
- Plants with male and female flowers on different plants
- Individual plants are effectively male or female
- Can be describes as unisexual
- e.g. Juniperus communis
- e.g. Ilex aquifolium
19
Q
3.14 State the meaning of ‘pollination’
A
- Transfer of pollen from anther to stigma of a flower
- First step in the process leading to fertilization.
20
Q
3.15 Describe the characteristics of wind pollinated plants
A
- Inconspicuous often green colour
- Minimal or no flowers
- Scentless
- Necterless
- They have vast amounts of very light pollen
- Stigma is proportionally larger, feathery and very sticky adapted to attract pollen
- E.g Grasses and many Trees (Oaks, wheat, rice, barley)
21
Q
3.15 Describe the characteristics of bee (insect) pollinated plants
A
- Bright colourful flowers
- Often scented to attract pollinators
- Contain nectar to entice reward visiting pollinators
- Stigma and stamen tend to be shorter and sturdy
- Larger, heavier pollen grains produced in smaller quantities
- Not all plants can be pollinated by all bees, some need larger bee’s or other insects and may have specialised petals to attract a specific species
- Not just bees/ insects, may also be bats, birds)
- E.g Tomatoes, apples, beans
22
Q
3.21 State the meaning of the term ‘fertilisation’
A
- The result of one male gamete, from pollen, reaching a female gamete, an egg cell, in the ovule which produce a new embryo of the same species
- The pollen must be deposited on the right female part of the flower - Stigma
23
Q
3.22a State the meaning of the term fruit
A
- Formed from the ovary wall usually following fertilisation and encloses the seed
24
Q
3.22b State the meaning of the term seed
A
- The structure that develops from the ovule after fetilisation, it contains the plant embryo
- Contains nutrients to survive
25
3.22a State the function of **fruits**
* Seed **distribution**
* **Protection** of the **seed** against extreme conditions
* **May impose dormancy / inhibit germination**
26
3.23b State the function of **seeds**
* **Protection** of the **embryo** against extreme conditions
* In annuals they **allow seed to survive** unfavorable conditions
* **May impose dormancy** until favorable conditions arise
* **Gives rise to new plants**
* Transmit **genetic diversity**
* Shape and size have developed to aid **distribution**
27
3.24a Describe the means by which seeds are dispersed: **wind.**
Name **two** plant examples for the above
Seeds are dispersed by **wind** in the following ways:
* **Wing** some woody species produced winged fruits
* **Parachute** some fruits have tiny feathery parachutes
* E.g ***Acer*** sp
28
3.24b Describe the means by which seeds are dispersed: **water**.
* Aquatic plants or those growing close to rivers and seashores **use the moving water to aid seed dispersal**
* **Buoyant** fruit or seed is carried away by the moving water
* E.g ***Nymphaea*** spp (water lilies)
29
3.24c Describe the means by which seeds are dispersed **explosive.**
* **Fruit splits open propelling the seeds into the air**
* Can be caused by a **build up of water pressure**
* Or due to tension caused as the **seed dries**
* E.g ***Geranium*** sp
30
3.24d Describe the means by which seeds are dispersed: **animals**.
* **Attachement** hooked fruits become attached to animal fur when the plant is brushed against
* **Scatter hoarding** birds or mamals may collect and disperse fruits, such as squirrels collecting acorns from oak trees e.g. ***Quercus robur***
* **Frugivory** fruits are eaten by animals, the seeds pass though the animals digestive system to be deposited elsewhere
31
3.25c Describe and state the function of the **testa**
* **Seed coat**
* **Encloses** the **embryo**
* **Waterproof** and **air tight**
* **May contain germination inhibitors** enabling dormancy until favourable conditions (after cold winter, or fire)
* **Protects** the **embryo against** **physical damage** and **desication**
32
3.25d Describe and state the function of the **cotyledon**
* **Seed leaf**
* Part of the **embryo**
* May be **one or two** depending on whether it is a moncotyledon or dicotyledon
* Becomes the **first leaf / leaves** of a seedling when germination occurs
* May occupy a large part of the seed
* Once grown is the first site of **photosynthesis**
* May also act as a **food store** for the embryo
33
3.25f Describe and state the function of the **embryo**
* **Contained in a seed**
* **Immature plant** waiting for favorable growing conditions
* Consisting of **cotyledon/s** (seed leaves), **radicle** (root) and **plumule** (stem)
* Once the embryo begins to germinate it is called a **seedling**
34
3.25g Describe and state the function of the **radicle**
* Part of the embryo which develops into the **first root** arising from the germinating seed
* **Embryonic root** system which will **take up water and nutrients** from the earth
35
3.26a Describe **Epigeal germination**
* Meaning '**above ground**'
* The **epicotal** lengthens pushing seed above ground
* The **cotyledons** then emerge above ground
* E.g *Brassica spp* (Cabbage)
36
3.26b Describe **Hypogeal germination**
* Means ‘**below** **ground’**
* The **cotyledons** stay below ground level
* The **plume** pushes through the earth to the light
* E.g *Phaseolus vulgaris* (French bean)
37
State the differences between **sexual and vegetative** reproduction in plants
Sexual
* Usually involves **flowers**
* Fusion of male and female **gametes**
* Produces **seed**
* Genetic **diversity** is possible
* Therefore **adaption** to changing environments
* e.g ***Calendula officinalis***
Vegetative
* **Non-sexual**
* Can be **natural** (Rhizomes, suckers)
* **Nursery** production (Division, cuttings)
* Offspring are **genetically identical**
* Not able to **adapt**
* e.g ***Ranunculus repens***
38
State the difference between **Indehiscent** and **dehiscent** fruit/seed
Indehiscent
* Fruit and seed are **combined**
* May need **decay to separate**
* E.g nuts, Hazel
* E.g Maple fruit
Dehiscent
* Fruit forms a **casing** to protect seed
* Casing needs to be **broken** for seeds to disperse
* E.g Poppy
