Chapter 29

Question 1

What organism first started “Greening the Earth”?

Answer 1

Cyanobacteria.

Question 2

What is the Oxygen Catastrophe?

Answer 2

When cyanobacteria started releasing too much oxygen, wiping out almost all anaerobic life.

Question 3

What started the Oxygen catastrophe?

Answer 3

Cyanobacteria.

Question 4

What are the 5 characteristics that are shared between land plants and algae?

Answer 4

1. Multicellular
2. Eukaryotic
3. Phostosynthetic Autotrophs
4. Cell Walls of Cellulose
5. Have Chloroplasts with both Chlorophyll a and b

Question 5

What are the 3 characteristics that charophytes share with land plants?

Answer 5

1. Rosette shaped cellulose-synethsizing complexes
2. Structure of Flagelleted sperm
3. Formation of Pharmoplast

Question 6

What are the benefits to a terrestrial habitat compared to an aquatic habitat?

Answer 6

1. Sunlight unfiltered by water and plankton
2. Atmosphere with more plentiful carbon dioxide than water
3. Soil rich in minerals & nutrients
4. Initially few herbivores & pathogens

Question 7

What is the closest relative to land plants?

Answer 7

Charophytes.

Question 8

What is Green Algae called?

Answer 8

Charophytes.

Question 9

What are the major adaptations that enabled plants to colonize land?

Answer 9

1. Charophyte algae inhabit shallow waters where they are subject to drying
2. Natural Selection favors survival without water
3. One adaptation is a protective layer that prevents zygotes from drying
4. Similar adaptations found in walls of plant spores

Question 10

What are the 5 main traits that appear in most land plants but not in charophyte algae?

Answer 10

1. Alternation of generations
2. Multicellular, dependent embryos
3. Walled spores produced in sporangia
4. Multicellular gametangia
5. Apical Meristems

Question 11

Describe Alternation od Generations.

Answer 11

Plants alternate between two multicellular stages: reproductive cycle call alternation of generations

Gametophyte (haploid)->produces haploid gametes by mitosis

Fusion of Gametes-> DIPLOID SPOROPHYTE, which produces HAPLOID SPORES by meiosis

ARE BOTH DIPLOID OR HAPLOID AT ONE POINT OR ANOTHER IN THEIR LIFE

Question 12

Describe MultiCellular Dependent Embryos.

Answer 12

Develop from zygotes (retained within the tissues of the female parent)

Nutrients are transferred from parent to embryo through placental transfer cells

Land plants are called EMBRYOPHYTES becasue of the dependency of the embryo on the parent

LIVE OFF OF MOM OR FEMALE PARENT AS EMBRYO

Question 13

What are some of the advantages and disadvantages to MultiCellular Dependent Embryos?

Answer 13

The embryo is very protected and doesn’t need to rely on tissue from the environment, however the embryos drain nutrients from parent plant and the maternal plant has to give those nutrients to thousands.

Question 14

Describe Walled Spores in Spogarania.

Answer 14

Spores are haploid reproductive cells with outer wall that protects them in a dry terrestrial environment

SPORANGIA is an organ that produces spores

Diploid cells called SPOROCYTES undergo meiosis to generate haploid spores

Question 15

Describe Multicellular Gametangia.

Answer 15

Gametes are produced within organs called GAMETANGIA.
enclose and protect plant cell.

Question 16

What are the different terms for females realting to Multicellular Gametangia?

Answer 16

Female gametangia, called ARCHEGONIA, produce eggs and are the site of fertilization
(yellow egg)

Question 17

What are the different terms for males realting to Multicellular Gametangia?

Answer 17

Male gametangia, called ANTHERIDIA, produce and release sperm
(brown sperm)

Question 18

Describe Apical Meristrems.

Answer 18

Plants sustain continual growth in their APICAL MERISTEMS

Cells from the apical meristems differentiate into various tissues

Question 19

What are some other adaptations that land plants have?

Answer 19

1. Cuticle
2. Stomata
3. Mycorrihaze

Question 20

What is the protective layer that prevents zygote from drying out?

Answer 20

It’s called the sporopollenin.

Question 21

What are the major phyla of extant Brophtye plants?

Answer 21

-Bryophytes represented by 3 phyla of small herbaceous (non-woody), nonvascular plants
-were thought to represent the earliest lineages to diverge from the common ancestor of land plants
1. phylum Hepatophyta
-liverworts
2. phylum Bryophyta
-mosses
3. phylum Anthocerophyta
-hornworts

Question 22

What are Bryophotes?

Answer 22

Categories separates into 3 main sections. Liverworts, Mosses, and Hornworts. Thought to be earliest lineages of land plants.

Question 23

How do mosses impact Nitrogen availability?

Answer 23

-mosses are capable of inhabiting diverse and sometimes extreme environments (common in moist forests and wetlands)
-some mosses might help retain nitrogen in the soil
-mosses act like a sponge and hold nutrients and moisture in the soil

Question 24

Why does Nitrogen availability matter?

Answer 24

-nitrogen is one of the biggest limiting resources that a plant needs for growth

Question 25

What is a seedless vascular plant?

Answer 25

-seedless vascular plants have flagellated sperm and are usually restricted to moist environments -reproduction in these plants required water to carry egg/sperm for fertilization -vascular tissue allowed for increased height which produced an evolutionary advantage

Question 26

What are the various structures and functions found in vascular plants?

Answer 26

1. xylem 2. phloem 3. roots 4. leaves

Question 27

What is the historical and ecological structure of seedless vascular plants?

Answer 27

-ancestors of modern lycophytes, horsetails, and ferns grew to great heights during the Devonian and Carboniferous periods forming the first forests -increased growth and photosynthesis removed carbon dioxide from the atmosphere and may have contributed to global cooling at the end of the Carboniferous period -plants of these Carboniferous forests eventually became coal because there were no microbes to digest lignin and cellulose and the layers of lignin and cellulose were compressed into the Earth -the end of the Carboniferous period marked an increased prominence of seed plants (mostly gymnosperms but later angiosperms dominate)

Question 28

Why was the ocean green during the Archaean?

Answer 28

-oceans were full of iron causing green rust to form where there's a lack of oxygen -oxygen was in short supply everywhere in the Archean

Question 29

How and why did the oceans color change in eons after the Archaean?

Answer 29

-photosynthesizers showed up and started to produce more oxygen -bacteria (blue-green cyanobacteria or purple microbe called halobacteria) -photosynthetic bacteria changed the chemical balance of the entire biosphere and eventually altered the face of our planet -oxygen from these new bacteria began reacting with the iron in the oceans turning the oceans from green to a deep blood-red as the seas begin to fill with iron oxide (rust)

Question 30

How did the first photosynthetic organisms change our planet?

Answer 30

-photosynthetic organisms used up most of the carbon dioxide in the atmosphere which caused the temperature to drop and had released more oxygen into the atmosphere -oxygen reacts with methane and takes it out of circulation -photosynthetic organisms decreased the levels of greenhouse gases which triggered a global glaciation -photosynthetic organisms needed CO2 to survive but they were continually pumping out oxygen -photosynthetic organisms suffocated by their own waste and anaerobic life was largely wiped out -The introduction of photosynthetic organisms caused drastic changes in the climate and radically different chemistry of the planet pushing most of life to the brink of extinction

Question 31

What are phragmoplast?

Answer 31

-a group of microtubules that forms between the daughter nuclei of a dividing cell.

Question 32

How did the accumulations of the major adaptations by charophyte ancestors that enabled plants to colonize land impact their descendants?

Answer 32

-accumulation of the major adaptive traits by some charophyte ancestors probably enabled their descendants to survive out of water permanently

Question 33

What is the stomata?

Answer 33

Specialized cells allowing for gas exchange from plant and environment. They can adapt to environment and location of stomata is in different locations on plants.

Question 34

What is mycorrihaze?

Answer 34

Associations between fungi and plants that could have helped plants without true roots get nutrients. It increases surface area of plant to capture more and helps to hold roots in place.

Question 35

What can land plants be informally grouped by?

Answer 35

Presence or absence of vascular tissue.

Question 36

What can land plants be informally grouped by?

Answer 36

Presence or absence of vascular tissue.

Question 37

What life cycles dominate mosses and other nonvascular plants?

Answer 37

-dominated by gametophytes -they are usually larger and longer-living than the sporophytes

Question 38

What is a Brophyte?

Answer 38

-A non vascular plant -Can grown in very few conditions due to lack of vascular tissue -Don't grow tall -Very reduced root system

Question 39

What are xylem?

Answer 39

-conducts most of the water and minerals -includes tracheids (tube-shaped cells) -water conducting cells are strengthened by lignin (gives wood properties) and provide structural support

Question 40

What are pholem?

Answer 40

-cells arranged into tubes that distribute sugars, amino acids, and other organic products

Question 41

What are roots?

Answer 41

-organs that anchor vascular plants -enable vascular plants to absorb water and nutrients from the soil -may have evolved from subterranean stems

Question 42

What are leaves?

Answer 42

-organs that increase the surface area of vascular plants and allow capturing of more solar energy to be used for photosynthesis -they are highly adapted to the environment they live in

Question 43

What are the living vascular plants characterized by?

Answer 43

1. life cycles with dominant sporophytes (instead of gametophytes like in bryophytes) 2. vascular tissues called xylem and phloem 3. well-developed roots and leaves

Question 44

What are the 2 clades that divide seedless vascular plants?

Answer 44

1. phylum lycophyta -club mosses, spike mosses, and quillworts 2. phylum monilophyta -ferms, horsetails, whisk ferns and relatives

Question 45

Why are ferns an important example of phylum monilophyte?

Answer 45

-ferns are the most widespread seedless vascular plants with more than 12,000 species -most diverse in the tropics but also thrive in temperate forests

Question 46

Why are horsetails an important example of phylum monilophyte?

Answer 46

-were diverse during the Carboniferous period but are now restricted to the genus Equisetum -jointed plants (stems have joints and are the main photosynthetic organ)

Question 47

Why are whisk ferns and their relatives important examples of phylum monilophyte?

Answer 47

-they resemble ancestral vascular plants but are closely related to modern ferns

Question 48

What are the 2 groups that seed plants can be divided into based on the absence or presence of enclosed chambers in which seeds mature (divide living seed plants)?

Answer 48

1. gymnosperms - naked seed plants -conifers 2. angiosperms -flowering plants -90% of living plants species are angiosperms

Question 49

What is the closest relative of land plants?

Answer 49

Charophytes.