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Flashcards in Transport In Plants Deck (37):
1

3 reasons multicellular plants need transport systems

Metabolic demands
Size
SA:V ratio

2

What are dicotyledonous plants

Make seeds containing 2 cotyledons (organs that act as food stores for the developing embryo plant)

3

What are herbaceous dicots

Soft tissues
Short life cycle

4

What are woody dicots

Hard lignified tissues and long life cycle

5

What is a vascular system

Series of transport vessels running through the stem, roots and leaves

6

What is the vascular system in the dicots

Xylem and phloem arranged into a vascular bundle in the leaves, steam and roots

7

Osmosis

Net movement of water molecules through a partially permeable membrane from a region of high water potential to a region of lower water potential
(Passive)

8

Water potential

The tendency of water molecules to move from one place to another
(0 is highest)

9

Hypotonic

Less solute concentrated

10

Isotonic

Equal amounts of solute and water

11

Hypertonic

More solute concentrated

12

Xylem

Transports water and mineral ions (one way)
Dead cells
Columns of cambium cells
Lignin in walls (support and waterproof)
Bordered pits (water leaves xylem and moves to other cells)
Passive

13

Phloem

Transports food (unidirectional)
Living cells
Companion cells have nucleus and linked by plasmodesmata
Active

14

Vascular bundle

Phloem (outside)
Xylem (inside)
Cambium cell’s (divide)

15

Photosynthesis equation

6CO2 + 6H2O —> C6H12O6 + 6O2

16

Root cells

Microscopic size- penetrate easily
Large SA:V
Thin surface area
Water potential gradient

17

Symplast pathway

Cytoplasm
Water moves via osmosis
Water from soil moved from root hair cell to next cell until xylem reached

18

Apoplast pathway

Cell walls and intercellular spaces
Water movies into xylem and cohesion pulls other molecules
Creates tension

19

Explain the movement of water into xylem

Water moves from roots in apoplast/symplast pathway
Casparin strip (Suberin) makes cells waterproof
Water in A blocked and must join S

20

Cohesion tension theory

Model of water moving from the soil in a continuous stream up the xylem and across the leaf

21

What do cells use water for?

Photosynthesis
Maintaining cell turgidity
Making new cells

22

What abiotic factors affect water loss

Temperature
Light intensity
Humidity
Amount of air movement
Availability of soil water

23

Transpiration

Evaporation of water vapour from the surfaces of plants

24

What biotic factors affect water loss

Stomatal pore size
Stomata frequency and distribution
SA:V
Thickness of cuticle
Ability to absorb soil water

25

Xerophytes

Plant that is adapted to live in conditions in which there is a scarcity of water in the environment
Cacti

26

Adaptations of xerophytes

Reduced no. of stomata/sunken stomata
Reduced leaves/leaf loss
Hairy/curled leaves
Long roots
Thick wavy cuticle

27

Hydrophytes

Plants growing in water and contain many aerenchyma
Water lily

28

Adaptations of hydrophytes

Large/thin leaves
Very thin or no waxy cuticle
Large air sacs
Many always open stomata
Large SA

29

Translocation

The movement of assimilates

30

Symplast route of translocation

Assimilates move through cytoplasm of mesophyll (Passive)

31

Apoplast route of translocation

Assimilates diffuse through cell wall
Reach companion cells and actively transport across membrane with H+ ions (co transport)

32

Evidence for phloem as tissue for translocation

Swollen after ringing
Radioactive tracers
Aphids
Electron microscopy

33

Pressure flow hypothesis

Movement of sap through phloem

34

What does potometer do

Measures water uptake

35

How does the movement of phloem sap occur

By mass flow from sucrose sources to sucrose sinks

36

Active transport

Movement of particles across a plasma membrane against a concentration gradient

37

what are the gaps in the cell walls between companion cells and sieve tube elements called

plasmodesmata