Chapter 25 and 26 Stems

Question 1

What has the largest stem in the world?

Answer 1

Adonsonia Boabab

Question 2

What has the tallest stem in the world?

Answer 2

Douglas Fir

Question 3

What has the stem with the most volume?

Answer 3

giant sequoia

Question 4

What are the six functions of stems?

Answer 4

support of above-ground parts of plants (leaves and flowers)
transport (by conduction)
storage (tubers and bulbs)
protection
photosynthesis 
reproduction

Question 5

What is a node and why are they important?

Answer 5

a node is a spot where leaf connects to stem. It adds plumbing needed and the presence of nodes make stems more plex than roots.

Question 6

What is an internode?

Answer 6

stem section between two nodes

Question 7

Describe the dicot stem pattern as described in lecture.

Answer 7

1. the primary vascular tissue with separate vascular bundles organized in a ring.
2. the primary Phloem is outside while the primary xylem is inside.
3. has a pith.
   vascular bundles are open (they are forming the vascular cambium.
4. if you see sclerenchyma bundles or sheath it’s now closed.

Question 8

Describe the second dicot pattern of stems discussed in lecture.

Answer 8

wider vascular bundles that touch
xylem in, phloem out
primary vascular tissue appears as cylinder
common in stems that undergo a lot of secondary growth.

Question 9

Describe the monocot stem structure discussed in lecture.

Answer 9

vascular bundles are scattered throughout ground tissue (but not random)
ground tissue is not separated into a pith and cortex.
vascular bundles form screaming monkey face.

Question 10

what is the stolon?

Answer 10

a horizontally oriented stem above ground (we know its a stem because of nodes)

Question 11

How do tendrils grow?

Answer 11

up and around support structure.

Question 12

What are thorns?

Answer 12

pointy objects that are for defense.

Question 13

What does a succulent stem store?

Answer 13

it stores water.

Question 14

What is a cladophyll?

Answer 14

(branch leaf) flattened stem that is photosynthetic.

Question 15

Leaves always grow…

Answer 15

below the bud.

Question 16

What is a Rhizome?

Answer 16

a horizontally oriented stem below ground.

Question 17

What is a bulb?

Answer 17

a small stem surrounded by thick fleshy leaves.

Question 18

What is a corm?

Answer 18

a fleshy stem surrounded by thin, papery leaves.

Question 19

What are tubers?

Answer 19

fat, underground storage stem (like potatoes).

Question 20

The eyes of a potato are also…

Answer 20

stem nodes.

Question 21

When viewed under a microscope, the eyes of a potato closely resemble what?

Answer 21

an apical meristem

Question 22

What three stems also serve as storage structures that we discussed in lecture?

Answer 22

bulbs, corms, and tubers.

Question 23

What are the two secondary meristems that produce secondary growth?

Answer 23

vascular cambium, and the cork cambium.

Question 24

Most secondary growth comes from which secondary meristem?

Answer 24

the vascular cambium.

Question 25

How thick is the vascular cambium?

Answer 25

one cell thick.

Question 26

What does the vascular cambium produce?

Answer 26

the secondary xylem and phloem.

Question 27

When is the epidermis lost?

Answer 27

during secondary growth.

Question 28

How do you tell the difference between a stem and a root?

Answer 28

a stem will have a pith and a root with have the primary xylem.

Question 29

What is the cork cambium responsible for producing?

Answer 29

the periderm.

Question 30

What are the names of the three cuts we can make in woody stems?

Answer 30

cross-section, radial, and tangential.

Question 31

Which cut goes through the middle of the stem?

Answer 31

radial.

Question 32

Pine, spruce, juniper, and redwood are all examples of...

Answer 32

conifers which produce soft wood.

Question 33

Oak, maple, walnut, and birch are all...

Answer 33

angiosperms and make hard wood.

Question 34

Why are conifers considered homogenous?

Answer 34

they have few cell types, they have tracheids but no vessels, rays are 1 cell wide, and resin ducts can be present.

Question 35

What purpose do resin ducts serve?

Answer 35

defensive strategy against insects.

Question 36

Why are angiosperms (hard wood) considered heterogenous?

Answer 36

they have many cell types, tracheids and vessel elements, fibers, both heavy density and finer grain, parenchyma, rays are more than 1 cell wide, and lack resin ducts.

Question 37

The vascular cambium goes through two growth periods throughout the year. Name them.

Answer 37

Spring wood: (cell w thin walls and wide lumens.) | Summer wood/late wood: cells with thick cells walls and narrow lumen.

Question 38

True or False. heartwood is neccessary for the life of the tree.

Answer 38

False.

Question 39

What is heartwood?

Answer 39

older, central wood that is not conducting, sometimes dark in color.

Question 40

What is sap wood?

Answer 40

conducting wood that is younger than heartwood, farther out and lighter in color.

Question 41

What are the functions of the secondary phloem?

Answer 41

transports sugars, the innermost layer is functional for transport, the rest is crushed, and the youngest part is the ring just outside the vascular cambium.

Question 42

The periderm is a collection of what three tissues?

Answer 42

cork, cork cambium, an phelloderm.

Question 43

How can you tell you are looking at the periderm?

Answer 43

the cells like up well.

Question 44

What type of wax do cork cells have that make them impermeable to water and gas exchange?

Answer 44

suberin.

Question 45

Where is the tree alive?

Answer 45

between the vascular cambium and the cork cambium.

Question 46

What are lenticels?

Answer 46

holes through the periderm that allow for gas exchange.

Question 47

Bark is considered to be what?

Answer 47

everything past the cork cambium.

Question 48

Outer bark is...

Answer 48

tissue outside the innermost cork cambium.

Question 49

Inner bark is...

Answer 49

tissue between the vascular cambium and the cork cambium.

Question 50

Which of these is non-living? Phloem, cortex, cork, or phelloderm.

Answer 50

cork is non-living.