9.1 Plant Structure and Growth Flashcards Preview

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Flashcards in 9.1 Plant Structure and Growth Deck (37):
1

Define Vascular plant

Vascular Plants have conductive tissues (a vascular system) for transporting water, minerals and nutrients throughout the plant

2

Describe the difference in number of cotyledons between monocotyledons and dicotyledons

Monocotyledons have one cotyledon; dicotyledons have two

3

Describe the difference in leaf shape between monocotyledons and dicotyledons

Monocotyledons have oblong or linear shaped leaves; dicotyledons have broad leaves

4

Describe the difference in leaf veins between monocotyledons and dicotyledons

Monocotyledons have parallel venation; dicotyledons have net-like venation

5

Describe the difference in root structure between monocotyledons and dicotyledons

Monocotyledons have fibrous, adventitious roots; dicotyledons have tap roots with lateral branches

6

Describe the difference in number of floral organs (petals) between monocotyledons and dicotyledons

Monocotyledons have them in multiples of 3; dicotyledons have them in multiples of 4 or 5

7

State the location of the phloem, and the importance of this

Found in middle of leaf, allowing for optimal access for all cells

8

State the function of the phloem

Transports the products of photosynthesis (sugars, amino acids) to the rest of the plant

9

State the location of the xylem, and the importance of this

Found in middle of leaf, allowing for optimal access for all cells

10

State the function of the xylem

Transports water and minerals into the leaf tissue from the stem and roots

11

State the location of the upper epidermis, and the importance of this

On top of leaf, where light intensity and heat are greatest

12

State the function of the upper epidermis

Secretes waxy cuticle which conserves water

13

State the location of the lower upper epidermis

Bottom of leaf

14

State the function of the lower epidermis

Contains stomata pores which allows for gas exchange, mainly CO2

15

State the location of the palisade mesophyll and the importance of this

Upper half of leaf where light intensity is greatest (upper epidermal cells are transparent)

16

State the function of the palisade mesophyll

Main region of photosynthesis; cells absorb light

17

State the location of the spongy mesophyll and the importance of this

Lower half of leaf, near stomatal pores where gases and water are exchanged with the atmosphere

18

State the function of the spongy mesophyll

Main site of gas exchange

19

State the location of the vascular bundles, and the importance of this

Middle of leaf, allowing for optimal access for all cells

20

State the function of the vascular bundles

Spread through the leaf like a network, providing support and transporting water and the products of photosynthesis

21

State the location of the stomata

Bottom of leaf

22

State the function of the stomata

Allows movement of gasses in and out of the leaf

23

Define Storage organ

A storage organ is a part of a plant specifically modified to store energy. They are usually found underground (better protection from herbivores).

24

State the function and give an example of storage roots

Modified roots which store water or food; carrots

25

State the function of and give an example of stem tubers

Horizontal underground stems which store carbohydrates; potatoes

26

State the function of and give an example of bulbs

Modified leaf bases which allow for food storage and contain layers called scales; onion

27

State the function of and give an example of tentrils

Modification to leafs which allow for climbing support and attachment; cucumber

28

Define meristems

Regions of plant tissue where undifferentiated cells undergo rapid cell division (mitosis), and therefore growth occurs.

29

State the two kinds of meristems which are found in dicots

Apical meristems and lateral meristems

30

State the location of apical meristems

Occur at the tips of the shoots and roots

31

State the location of lateral meristems

Formed from the cambium cells

32

Outline the function of apical meristems

Responsible for primary growth
Increases height/depth of plant
Produces new leaves and flowers

33

Outline the function of lateral meristems

Responsible for secondary growth
Increases girth of stem for strength
Produces bark on trees

34

Define tropism

Bending growth of a plant towards or away from a directional stimulus

35

Define phototropism

Bending growth of a plant towards a source of light

36

Define auxin

A group of substances that promote plant growth

37

Explain the role of auxin in phototropism

• Auxin makes plant cells enlarge and grow
• Auxin causes cell elongation by activating pumps that expel H+ ions from the cytoplasm into the cell wall
• The resulting decrease in pH within the cell causes cellulose fibres to loosen, as the bonds which hold them together are broken
• This makes the cell wall flexible and capable of stretching when water influx promotes cell turgor
• In the shoot, auxin is eradicated by light
• The greater presence of auxin on the shaded side of the plant causes this side to lengthen, making the shoot curve towards the light