Plant Organs

Question 1

what are the plant organs?

Answer 1

Stems
Roots
Leaves

Question 2

what root systems do monocots vs dicots have

Answer 2

monocots = fibrous root system 
dicots = taproot system (usually)

Question 3

What is the main different between monocots and dicots?

Answer 3

monocots have one cotyledon embryo

Dicots have two

Question 4

what difference is there in monocot vs dicot leaves?

Answer 4

Monocots = veins are usually parallel
Dicots = veins usually net-like

Question 5

what difference are there in monocot vs dicot stems?

Answer 5

Vascular bundles
Monocots = complexly arranged bundles
Dicots = arranged in a ring (usually)

Question 6

what difference are there in monocot vs dicot flowers?

Answer 6

Monocots = floral parts in multiples of 3
dicots = floral parts in multiples of four or five

Question 7

what is the difference between primary and secondary roots?

Answer 7

primary grow downwards

secondary branch outwards

Question 8

what are the 4 main types of root systems?

Answer 8

Taproot
Fibrous
Prop/ adventitious
Ariel

Question 9

What are the 3 main functions of roots?

Answer 9

absorb minerals and water from soil
anchor and support plant
store food made from photosynthesis

Question 10

What is the tip of the root called?

Answer 10

root cap

Question 11

What is the function of the root cap?

Answer 11

regulate primary growth of root through specialised meristem cells

Question 12

what kind of cells cover the root

Answer 12

a single layer of epidermal cells = epidermis

Question 13

what tissue is found beneath the epidermis of the roots?

Answer 13

ground tissue

Question 14

what type of tissue is found in the centre of roots?

Answer 14

vascular tissue

Question 15

what adaptation makes root vascular tissue efficient carriers for water and minerals?

Answer 15

they have a waxy layer to prevent leakage

Question 16

how many layers of epidermal cells make up the epidermis of the stem?

Answer 16

1

Question 17

what replaces the epidermis of trees?

Answer 17

bark

Question 18

what are the 3 main functions of stem?

Answer 18

to hold up leaves (for photosynthesis)
transport water and nutrients from roots to leaves
storage (only in some plants)
Structural support

Question 19

How does the phloem translocate sugar?

Answer 19

Pressure-flow hypothesis and turgid cell pressure

Question 20

when is stomata most open?

Answer 20

midday

Question 21

what are the 6 structural parts of the stem?

Answer 21

Node - where leaves attach
Internode - stem between nodes
Rhizome - horizontal underground stem
Tuber - underground stem for food storage
Bulb - large bud with layers for food storage
Corm - upright thickened underground stem

Question 22

what are very thick, specialised stems good for? Give an example

Answer 22

Storing lots of food and water - i.e: Australian baobab tree can store up to 120,000 L of water in trunk

Question 23

what are specialised vine stems good for?

Answer 23

clinging and climbing - have thicker, threadlike tendrils at ends to twine and grip surfaces e.g: devil’s ivy

Question 24

what are woody tree trunks specialised for?

Answer 24

strength and support - can grow very tall

Question 25

what are rhizomes specialised for? Give an example

Answer 25

vegetative asexual reproduction - have horizontal underground stems i.e: ginger, flag iris

Question 26

What are thorns specialised for?

Answer 26

Protection from herbivores

Question 27

what does the phloem move?

Answer 27

sugars mainly

Question 28

What does the xylem move?

Answer 28

water and nutrients

Question 29

which type of meristem causes stem length growth?

Answer 29

apical meristems

Question 30

which type of meristem causes stem girth growth?

Answer 30

lateral meristems

Question 31

What is bark made from?

Answer 31

Cork from cork cambium and phloem

Question 32

How does the pressure-flow hypothesis work?

Answer 32

- Sugar is loaded into sieve tube elements at source (usually leaves) by active transport - Water from xylem follows sugar into sieve tube element via osmosis - Creates high turgor pressure in phloem, forcing sugar and fluid to the sink (the root) - Sugar leaves phloem via active transport and water leaves via osmosis

Question 33

What is transpiration?

Answer 33

The process of water movement through a plant and its evaporation

Question 34

What is translocation?

Answer 34

the movement of materials from leaves to other tissues throughout the plant

Question 35

According to the cohesion-tension theory, what is the main driver of water movement in the xylem?

Answer 35

Transpiration