Bio 131 Lecture Exam 2

Front 1

cuticle

Back 1

The cuticle is a waxy outer layer of protection for leaves that helps retain water and protect from bugs and parasites.

Front 2

secondary metabolites

Back 2

Secondary metabolites are compounds that a plant produces that are not necessary for daily survival. However, compounds produced (basil, tobacco, etc.) can protect the plant from being eaten because these compounds can be harmful when ingested in large amounts.

Front 3

evolutionary steps of plants

Back 3

1. movement onto land

2. evolution of vascular systems

3. evolution of seeds

4. evolution of flowers and fruits

Front 4

how did charophyceans evolve onto land?

Back 4

Charophyceans originally lived in water. Some lived in shallow waters and were periodically exposed to air. Those that survived this exposure lived on to reproduce and gradually moved onto land over generations.

Front 5

what are the general characteristics of mosses/bryophytes?

Back 5

Mosses live in moist environments. They don't have any seeds or vascular systems - they are seedless nonvascular plants. They reproduce using spores and require water for fertilization. Their dominant life cycle is haploid gametophyte.

Front 6

shared derived characters of vascular seedless plants?

Back 6

- alternation of generations

- multicellular gametangia (make gametangia by mitosis)

- have apical meristems for growth

- produce spores w/ spore pollein cell walls

Front 7

why was the evolution of vascular tissue important?

Back 7

The evolution of vascular tissue was important because it allowed plants to live in drier environments. Vascular systems allow plants to take water/nutrients from soil and feed the plant. It also meant that plants could grow taller, thus escaping space limitations.

Front 8

how did leaves evolve?

Back 8

They evolved to become larger, meaning more surface area and therefore more photosynthesis. They have megaphylls (leaves with highly branched systems) and microphylls (small spine-shaped leaves). Megaphylls evolved when many close branches webbed together and formed a system.

Front 9

how did roots evolve?

Back 9

Roots evolved from extensions of the stem into soil.

Front 10

heterosporous vs. homosporous plants

Back 10

Homosporous plants only produce one type of sporangia which produces one type of spore. Heterosporous plants have microsporangia and megasporangia. Microsporangia produce microspores which produce male gametophytes. Megasporangia produce megaspores which produce female gametophytes.

Front 11

general characteristics of pterophytes (ferns)

Back 11

Ferns don't have true leaves. They require water for fertilization. They live in moist areas. They are vascular seedless plants.

Front 12

shared derived characters of seed plants that made them better adapted to the environment

Back 12

The evolution of seeds made it so that water was not necessary for fertilization, allowing the plants to live in drier environments.

Front 13

general characteristics of gymnosperms

Back 13

Gymnosperms have "naked seeds". They are fertilized when wind carries pollen to them and fertilizes the egg. They lack flowers and fruits.

Front 14

shared derived characters of angiosperms

Back 14

Angiosperms developed seeds with an endosperm for protection and feeding purposes. They produce fruits and flowers to help aid in seed dispersal. They evolved about 150 million years ago.

Front 15

how did the ovary evolve from leaves?

Back 15

It was thought that a leaf rolled into a tube to protect the ovule, and this eventually developed into protection for the ovule which became the ovary.

Front 16

characteristics of xylem

Back 16

Xylem aids in the transport of water and minerals and nutrients throughout the plant. Makes up the rings of trees.

Front 17

characteristics of phloem

Back 17

Phloem aids in feeding the plant (glucose). Makes sugar. Phloem rings are crushed as new ones grow from the inside.

Front 18

diffusion

Back 18

Diffusion is the spreading of molecules throughout water until at equilibrium or equal concentration. Water moves to areas with a lower water potential (or higher concentration).

Front 19

osmosis

Back 19

Osmosis is the movement of water through a semipermeable membrane. Usually, large or charged molecules will not be allowed through.

Front 20

water potential

Back 20

Water potential is impacted by concentration of solute and pressure. Low pressure = low water potential = high solute concentration. Water moves to areas with a lower water potential.

Front 21

apoplastic and symplastic transport

Back 21

Apoplastic transport is when water and minerals don't move through the cytoplasm, but moves around the cell through air spaces or cellulose. Symplastic transport is when water and minerals travel through the cytoplasm through a semipermeable membrane, which uses membrane-bound proteins to determine what is allowed through.

Front 22

how does water and minerals move from soil into the stele of roots?

Back 22

Using cohesion and adhesion. Cohesion is water bonding to other water. Adhesion is water bonding to other substances.

Front 23

casparian strip

Back 23

The casparian strip is a waterproof band that forces water through the endodermal cell and regulates what water and minerals enter the stele.

Front 24

phloem movement

Back 24

Phloem moves through sieve tubes to a lower water potential. Companion cells aid in the transport of the sugar into the tubes.

Front 25

transpiration

Back 25

Transporation is the evaporation of water out of the leaves. This happens because the leaves have a lower water potential and the water moves to the leaves and then evaporates.