Chapter 35 - 4

Question 1

What is secondary growth?

Answer 1

The growth of a plant in width (lateral)

Question 2

Secondary growth increases plant ________ width.

Answer 2

Width

Question 3

What tissue structure causes secondary growth?

Answer 3

Lateral meristems

Question 4

Where are lateral meristems the most common?

Answer 4

Root and Stems, not often found in leaves

Question 5

Why did lateral meristems likely evolve?

Answer 5

Competition, the fight for height which allows for more direct sun. This required a stable base.

Question 6

What are the 2 basic components in lateral meristems?

Answer 6

Vascular cambium
Cork cambium

Question 7

What does vascular cambium add?

Answer 7

Secondary xylem

Question 8

What does cork cambium add?

Answer 8

Waxy cells, rising bark and other components (periderm)

Question 9

What is the vascular cabium?

Answer 9

Cylinder or ring of meristematic cells. (only one layer) that creates secondary tissue between xylem and phloem. Also creates vascular rays to connect secondary xylem and phloem. Nutrient transport and repair.

Question 10

What 2 tissues is the vascular cambium between?

Answer 10

Xylem and Phloem

Question 11

How does growth work in the vascular cambium because it is only one cell thick?

Answer 11

Adds rings and thickness to the phloem and more rings to the xylem.

Question 12

What is dendrochronology?

Answer 12

The process of analyzing growth rings in a tree to figure out life span.

Question 13

What are the rings in tree roots made out of?

Answer 13

Xylem.

Question 14

What does early season xylem growth look like

Answer 14

Rapid, creating thick, light colored bands.

Question 15

What does late season xylem growth look like

Answer 15

Slow, creating dark colored bands. “The Circles”

Question 16

How would the bands be different in rainy years?

Answer 16

They would be exceptionally light and much bigger before the dark bands.

Question 17

How would the bands be different in dry years?

Answer 17

There would be only dark colored bands and they’d be a lot smaller.

Question 18

What are the 2 types of secondary xylem?

Answer 18

Heartwood
Sapwood

Question 19

What is heartwood?

Answer 19

The oldest xylem, doesn’t transport sap, water, or minerals. Provides structural support, but not much physiological support.

Question 20

What is sapwood?

Answer 20

The newer xylem, transports sap, and allows survival if the heartwood is damaged.

Question 21

What are the benefits of having distinct heartwood and sapwood?

Answer 21

Allows for survival if physical damage occurs to the outside of the tree. Allows for trees in tunnels because of the majority of heartwood.

Question 22

What is the cork cambium?

Answer 22

Contains meristematic tissue. Extremely thin. Doesn’t replace vascular tissue, replaces dried shed epidermis.

Question 23

What does the cork cambium create?

Answer 23

Cork cells. Forming protective periderm. Also creates secrete waxy protective compound called suberin.

Question 24

Is suberin hydrophobic or hydrophillic?

Answer 24

Hydrophobic.

Question 25

What is hydrophobic?

Answer 25

Something that repels water. Prevents water loss, physical damage, and pathogens.

Question 26

What does the cork cambium contain?

Answer 26

Lenticels.

Question 27

What are lenticels?

Answer 27

Horizontal slits that allow for gas exchange.

Question 28

What does the cork cambium contribute to?

Answer 28

Bark.

Question 29

What is bark?

Answer 29

By definition, the secondary phloem that transports sap (pitch). Also made up of the periderm.

Question 30

What is exposed when you peel off the bark on a tree?

Answer 30

The vascular cambium.

Question 31

What is inside of the bark?

Answer 31

Cork Cambium, Periderm, Cork Cells, Secondary Phloem