Plant Structure

Question 1

What is the role of the upper epidermis?

Answer 1

Protects waxy cuticle and is transparent so light can pass through

Question 2

What is the role of the palisade mesophyll?

Answer 2

Packed with chloroplasts/photosynthesis

Question 3

What is the role of the spongy mesophyll?

Answer 3

Contains air spaces for easy diffusion

Question 4

What is the role of the vascular bundle?

Answer 4

Supports the lead and contains xylem and phloem

Question 5

What is the role of the stoma (stomata)?

Answer 5

Gas exchange

Question 6

What is the role of the lower epidermis?

Answer 6

Contains stomata, produced waxy cuticle

Question 7

What is the role of the xylem?

Answer 7

Transports water and mineral ions

Question 8

What is the role of the phloem?

Answer 8

Transports ‘food’ (dissolved sugars)

Question 9

What is the role of the waxy cuticle?

Answer 9

Waterproof to prevent water loss

Question 10

What is the first things plants need?

Answer 10

The stuff for photosynthesis including CO2, H2O, light energy and chlorophyll to absorb it

Question 11

What is the photosynthesis equation?

Answer 11

CO2 + water –>Glucose + Oxygen
light

Question 12

Where does the CO2 and Water come from?

Answer 12

CO2-air via stomata
Water-soil via roots and xylem

Question 13

What is the Glucose and Oxygen used for?

Answer 13

Glucose-respired to release energy, make biomass and for proteins, lipids, vitamins and other carbs (starch)

Question 14

What is the second thing plants need?

Answer 14

Oxygen for aerobic respiration

Question 15

What is the third thing plants need?

Answer 15

Glucose for respiration and to make:
-Starch (storage)
-Cellulose (cell walls)
-Nucleic Acids
-Proteins for growth & repair
-Fats and oils
-Other sugars

Question 16

What is the fourth thing plants need?

Answer 16

Mineral ions e.g. nitrates to make amino acids, nitrates and phosphate to make nucleic acids and Mg 2+ ions to make chlorophyll

Question 17

Why do large plants need a transport system?

Answer 17

As they have a small SA:V ratio so need it to move water and mineral ions and food

Question 18

How is water and mineral ions transported and what by?

Answer 18

Roots to leaves via xylem

Question 19

How is assimilates (food) transported and what by?

Answer 19

Where they are needed via phloem

Question 20

Gases aren’t transported via the transport system. Why?

Answer 20

As plants have a low metabolic rate so can exchange sufficient O2/CO2 by diffusion through their outer surface

Question 21

What is the transport system in plants called?

Answer 21

Vascular System

Question 22

What is the Vascular System comprised of?

Answer 22

Xylem and Phloem Tissue

Question 23

What is the role of Xylem tissue?

Answer 23

To transport water and mineral ions from roots to the leaves and provide support
-up only

Question 24

What features do the Xylem have?

Answer 24

-No end plates between cells
-Vessel walls strengthened with lignin

Question 25

What is the role of phloem tissue?

Answer 25

Transports assimilates around plants in two directions

Question 26

What is a herbaceous dicotyledonous?

Answer 26

Flowering plant with woody stem

Question 27

What features do the phloem have?

Answer 27

Sieve plates between cells

Question 28

Xylem and Phloem are found in groups called...?

Answer 28

Vascular Bundles

Question 29

In the roots, where are these located?

Answer 29

At the centre

Question 30

Why are they located at the centre in the roots?

Answer 30

To prevent plant from being pulled out / protection

Question 31

In the stem, these are located near the...?

Answer 31

Edge

Question 32

Why are they located at the edge in the stem?

Answer 32

For strength and support

Question 33

What is the distribution of xylem and phloem in the leaves of herbaceous dicotyledonous plants?

Answer 33

-Vascular bundle in spongy meosphyll with the phloem on the bottom of the bundle -They form a network of veins stemming from the main midrib which helps support the leaf

Question 34

What is the distribution of xylem and phloem in the stem of herbaceous dicotyledonous plants?

Answer 34

-Vascular bundle around edge with phloem on outside. Provides a 'scaffolding' giving support to the stem and flexibility to allow the stem to bend -Xylem and Phloem separated by cambium -Parenchyma and Pith are packing tissues that separate and gives support for the vascular bundles

Question 35

What is the distribution of xylem and phloem in the roots of herbaceous dicotyledonous plants?

Answer 35

-Vascular bundles on inside for protection -Xylem form an x-shape in middle of bundle which provides strength for the root so it can push through the soil and helps anchor the plant to the ground -Phloem is to the outside of xylem -Pericyle protects vascular bundles and contains meristematic tissues allowing new roots to form

Question 36

What is Cambium?

Answer 36

Meristematic tissue that produces new xylem and phloem allowing the stem to widen and thicken as it grows