Plant structure and growth

Question 1

What is a vascular plant?

Answer 1

Land plants that have lignified tissues (the xylem) for conducting water and minerals throughout the plant

Question 2

What do the shoots of vascular plants consist of?

Answer 2

Roots: anchor the plant, and absorb and conduct water and minerals, and store food

Stem nodes: where leaves attach

Leaves: main organs of photosynthesis

Axillary buds: in axils of leaves and stems, give rise to branches

Plant organs may be adapted for specialized functions.

Question 3

What are the three tissue systems of vascular plants that are continuous throughout the plant?

Answer 3

Dermal, vascular, and ground

Question 4

What is the function of dermal tissue?

Answer 4

Protects against pathogens, herbivores, and drought, and aids in the absorption of water, minerals, and carbon dioxide.

Question 5

What is the function of vascular tissue and what is it made up of?

Answer 5

Long distance transport of substances. Phloem and xylem.

Question 6

What is the function of ground tissue?

Answer 6

Storage, metabolism, and regeneration.

Question 7

What are parenchyma cells?

Answer 7

Relatively unspecialized and thin-walled cells that retain the ability to divide. They perform metabolic functions of synthesis and storage.

Question 8

What are collenchyma cells?

Answer 8

They have unevenly thick, lignified walls that help support young, growing parts of the plant.

Question 9

What is lignin?

Answer 9

A complex organic polymer deposited in the cell walls of many plants, making them rigid and woody.

Question 10

What are schlerenchyma cells?

Answer 10

Fibers and sclereids, have thick, lignified walls that support mature, non-growing parts of the plant.

Question 11

What are the water conducting cells of the xylem?

Answer 11

Tracheids (are elongated cells in the xylem of vascular plants that serve in the transport of water and mineral salts, no perforated plates) and vessel elements (present in angiosperms but not gymnosperms), they have thick walls and are dead at functional maturity.

Question 12

What is the difference between angiosperms and gymnosperms?

Answer 12

Angiosperms, also called flowering plants, have seeds that are enclosed within an ovary (usually a fruit), while gymnosperms have no flowers or fruits, and have unenclosed or “naked” seeds on the surface of scales or leaves

Question 13

What is a meristem? Describe the different types.

Answer 13

A region of plant tissue, found chiefly at the growing tips of roots and shoots and in the cambium, consisting of actively dividing cells forming new tissue.

Shoot apical (tip)
Axillary bud (branching)
Lateral: Vascular cambium and cork cambium
Root apical (root tips)

Question 14

Describe primary growth

Answer 14

The root apical meristem generates new cells near the tip of the root, which allows the root axis and root cap to grow.

The apical meristem of a shoot is located in the apical bud, where it gives rise to alternating internodes and leaf-bearing nodes.

Question 15

What is the vascular cambium?

Answer 15

A meristemic cylinder that produces secondary xylem and secondary phloem during secondary growth.

Question 16

What does the cork cambium do?

Answer 16

Gives rise to thick protective covering called the periderm

Question 17

Describe secondary growth

Answer 17

Vascular cambium produces secondary xylem and phloem, older layers of secondary xylem (heartwood) become inactive, and younger layers (sapwood) still conduct water. The cork cambium gives rise to the periderm (the cork cambium plus layers of cork cells it produces).