3.2 Plants

Question 1

Why plants are important

Answer 1

plants support virtually all terrestrial and aquatic food webs

plants also provide a habitat for other organisms

Humans rely on plants for: medicines, clothing, wood, and paper products.

Question 2

How did plants evolve

Answer 2

Plants are thought to have evolved from charophytes, a group of green algae from the kingdom Protista (~400 million years ago)

Question 3

Adaptations for life on land:

Answer 3

waxy cuticle to prevent water loss, and stomata to allow gas exchange.

Question 4

Non vascular plant

Answer 4

Bryophyta

no true leaves, roots, or seeds

require wet conditions for fertilization

Mosses, liverwort

Question 5

Vascular plants

Answer 5

have xylem and phloem

Question 6

Seedless Plants (VP)

Answer 6

Produce spores instead of seeds
- Lignin is a tough fibrous substance that can provide more support

Question 7

Gymnosperms (naked seed)

Answer 7

uses cones with pollen or ovules

Question 8

Angiosperms (vessel seed)

Answer 8

Flowering plants

uses flowers with pollen and/or ovules to make seed-containing fruits

Question 9

Where are the gametophytes?

Answer 9

Seed-bearing plants have unicellular gametophytes, hidden inside the sporophyte (plant)

Pollen is the only type that can survive on its own. It releases the sperm when it pollinates a flower (the sperm go down to the ovule)

Question 10

SEEDS!

Answer 10

Seeds differ from spores because of extra layers of protection and a supply of food for the embryonic plant

Question 11

spore

Answer 11

tiny reproductive cell

Question 12

xylem

Answer 12

a vascular tissue in plants that transports water and dissolved minerals from the roots to the rest of the plant, primarily through the xylem vessels

Question 13

phloem

Answer 13

transporting organic material (carbon) such from the leaves to the rest of the plant

Question 14

Lycophytes

Answer 14

Club mosses

Question 15

Pterophytes

Answer 15

Ferns