Vascular Tissue

Question 1

• The transport system of the plant
• Comprised of three components:

Exterior Interior
<– phloem cambium xylem –>

Answer 1

vascular tissue

Question 2

Organization of vascular bundles is variable:

• form a complete _____ in the stem
• arranged as a _____ of bundles (dicot)
• vascular bundles __________ throughout the stem (monocot)

Answer 2

ring

circle

distributed (scattered)

VASCULAR TISSUE

Question 3

• Normally localized towards the _______ of the vascular bundle
• Primary function is to distribute photosynthate (_________) from leaves (source) to the rest of the plant

Answer 3

outside

fixed carbon

PHLOEM

Question 4

phloem is composed of 2 major cell types

a. _____________
- responsible for transport but lack a nucleus
- elongated cells with porous connections between the ends of cells (sieve plates)

b. _____________
- support the activity of the sieve tube

Answer 4

a. sieve tube members

b. companion cells

Question 5

• to provide a source of new cells for growth of the vascular system
• this is a ____________
• ___________ is a thin layer of undifferentiated cells between the phloem and xylem
• After division, this can produce either phloem or xylem cells
• essential for radial expansion of the stem

Answer 5

meristematic tissue
Cambium

VASCULAR CAMBIUM

Question 6

• Normally localized towards the INSIDE of the vascular bundle
• required for transport of water and nutrients from root throughout the plant
• Xylem cells die after _________
• Xylem contains several cell types
• _______, long and thin
• _______, short and fat

Answer 6

differentiation

Tracheids
Xylem vessels

XYLEM

Question 7

• Cell walls of these cells are thickened for strength
• Rings of _______ provide reinforcement
• Water and nutrients are moved through xylem vessels and tracheids arranged end to end
• __________ provide structural support and are an important component of hardwoods
• __________ are primary component of soft woods including pines

Answer 7

lignin

Xylem fibers

Tracheids

XYLEM

Question 8

• Innermost tissue of the stem
• Comprised of undifferentiated _____________
• Can function as a ________, for example in sugar cane
• May be _____________ in
  many woody plants

Answer 8

parenchyma cells

storage tissue

lost or reduced

PITH

Question 9

STEM STRUCTURE

Answer 9

EPIDERMIS
- epidermal
- guard cells

CORTEX
- parenchyma

VASCULAR SYSTEM
- phloem
- cambium
- xylem

PITH
- parenchyma

Question 10

STEM GROWTH

Answer 10

• primary growth
• secondary growth

Question 11

• new cells produced at the root tips and shoots
• increase in stem length

Answer 11

primary growth

Question 12

• increase in stem width

✓ ______________: produces tissue and increases thickness

✓ ______________: produces outer covering of stems

Answer 12

vascular cambium

Cork cambium

SECONDARY GROWTH

Question 13

formation of wood

Answer 13

wood
sapwood

Question 14

✔ layers of xylem produced year after year
✔ resulted from the older xylem not conducting water (heartwood)
✔ becomes darker with age

Answer 14

wood

Question 15

surrounds the heartwood

Answer 15

sapwood

Question 16

formation of bark

Answer 16

• All the tissues outside the vascular cambium
• Consists of outermost layers of dead cork
• Function: waterproof

Question 17

Stems: Internal Anatomy (Wood)

Answer 17

• bark
• heartwood
• sapwood

Question 18

old, inactive secondary phloem

Answer 18

bark

Question 19

old, inactive secondary xylem

Answer 19

heartwood

Question 20

new, active secondary xylem

Answer 20

sapwood

Question 21

• Lack secondary growth - because plants only live one year/growing season (annuals)
• Stems remain soft and flexible
• Buds lack protective scales (don’t need to survive harsh conditions)

Answer 21

herbaceous stems

Question 22

• Plants living and growing over multiple seasons have secondary growth (xylem, phloem) increasing diameter of the stems
• This is due to the ____________ which gives rise to the secondary xylem and phloem

Answer 22

vascular cambium

WOODY STEMS

Question 23

specialized stems

Answer 23

stolon
rhizome
tuber
bulb
section of a bulb
volubilate twining

Question 24

stems that grow aboveground:

Answer 24

1. tendrils
2. searcher shoots
3. stolons/runners
4. thorns/spines
5. cladodes/cladophylls
6. culms
7. succulent stems

Question 25

__________: long coiling structures that function for attachment and support of a climbing plant (_____)

Answer 25

tendrils sayote

Question 26

__________: stems with long internodes that move in circles through the air seeking support (_____)

Answer 26

Searcher shoots beans

Question 27

__________: horizontally oriented stems that grow along the soil surface; they function for vegetative reproduction due to the formation of roots at the nodes (_______ & ________)

Answer 27

Stolons/runners strawberry & bermuda grass

Question 28

__________: modified stems that protect the plant from grazers (_____ & _____)

Answer 28

Thorns/spines bougainvillea & lemon

Question 29

__________: flat, leaf-like stems modified for photosynthesis. (________ & ________)

Answer 29

Cladodes/Cladophylls asparagus, cactus

Question 30

__________: hollow or solid stem of grasses with distinct nodes and internodes, and sometimes form roots at the nodes (________ and ________)

Answer 30

Culms sugarcane & bamboo

Question 31

__________: store large amounts of water, common with plants in desert areas (_______)

Answer 31

Succulent stems cacti

Question 32

stems that grow underground

Answer 32

1. bulb 2. corn 3. rhizomes 4. tubers

Question 33

_______: large, roundish bud with a small basal stem at its lower part and its bulk being made of thickened scales which store nutrients (_____ & _____)

Answer 33

Bulb onions & tulips

Question 34

_______: stubby, short, fleshy, vertically-oriented stems that store nutrients (_______)

Answer 34

Corm gladiolus

Question 35

_________: underground stems that grow near the soil surface and have short internodes bearing scales; store food for renewing growth of the shoot after periods of cold weather (_____ & _____)

Answer 35

Rhizomes ginger & iris

Question 36

________: swollen regions of stems that store food; they bear buds called "______" (______)

Answer 36

Tubers eyes potatoes