Bio Exam Three

When did the first thin coating of cyanobacteria form?

1.2 BYA

When did the first small plants form?

500 MYA

How long ago did land plants appear?

370 MYA

What other group are land plants realted to?

Protists

What are the four main characteristics of Supergroup Chromalveolata Group Brown Algae?

1. Largest most complex algae

2. Commonly called sea weeds

3. Often resemble green plants

4. Exhibit alternation of generations

What are the three parts of a Brown algae?

Blade Stipe Hold fast

Alternation of generations

A complex type of life cycle in which a multi-cellular haploid stage alternates with a multicellular diploid stage

Can brown algae be haploid?

No. They are only ever diploid

Zoospores

All are structurally similar but half become female and half become male gametes.

What are three main characteristics of Supergroup Archaeplastida Clade Red algae?

1. Red photosynthetic pigment

2. Do not have a flagellated life stage

3. Red and green algae are the closest relatives to land plants

What are two main characteristics of Supergroup Archaeplastida Clade Green algae?

1. Closely related to green plants

2. Most live in fresh water

What characteristics are shared between land plants and protists?

1. Multicellular photosynthetic autotrophs

2. Cellulose in cell walls

3. Chloroplasts with chlorophylls a and b

What where the big advantages for plants to become terrestrial?

1. More exposure to sunlight

2. Atmosphere is abundant with CO2

3. Minerals in the soil to support growth

4. Few herbivores and pathogens initially

How did plants change the terrestrial environment?

1. Plant roots create habitat, and stabilize landscapes

2. Plants create oxygen through photosynthesis and take CO2 out of the atmosphere

3. They provided food

What is the closest relative to land plants?

Charophyceans (green algae)

What has lead us to believe that Charophyceans are the closest relative to land plants?

1. Rose shaped complexes that synthesize cellulose

2. Enzymes in peroxisomes

3. Structure of flagellated sperm is the same

4. Formation of phragmoplast

5. Plasmodesmata

Phragmoplast

A specialized cytoskeletal structure in plants and charophyceans

What does the phragmoplast do in the cell?

It moves the golgi vesicles to the center of the cell initiating cell plate formation and cell division

Plasmodesmata

Microscopic channels that connect the cells of charophceans and land plants

What separates plants from charophyceans?

plants are 1.apical meristems 2. alternation of generations (some algae but not charophyceans) 3. walled spores produced in sporangia 4. multicellular gametangia 5. multicellular dependent embryos

What are apical meristems?

Localized regions of cell division at the tips of shoots and roots. They differentiate into various tissues.

What are plant stem cells?

Apical meristems

Gametophyte ___ produce gametes by _____.

N; mitosis

______ 2N produce spores N by ______

Sporophyte; meiosis

Sporangium

Produces spores

Who has sporangium?

Plant sporophytes

Plants produce gametes within ____.

Gametangia

What is a male and female gametagnia called?

F: Archegonia

M: Antheridia

Where is the egg fertilized in plants?

Archegonia

Cuticle

Prevents water loss by covering the epidermis with a wax and polyester layer.

What produces secondary compounds?

Secondary metabolic pathways

How do we group plants?

Vascular tissue and reproductive structures

What does the Phloem do?

Push water down

What does the Xylem do?

Bring water up

Bryophytes

Nonvascular seedless plants

Fern and fern allies

Vascular seedless plants

Gymnosperms

Vascular naked seeds

Angiosperms

Vascular covered seeds

What is the dominant stage in the bryophytes?

Gametophytes

What must be present for sperm to swim to the egg in archegonia?

Water

Where does meiosis occur in the moss life cycle?

sporophytes

What releases spores from the sporangium into the environment during the moss life cycle?

Wind

Phylum anthrocerophyta are not very ___,___, or ____.

common, diverse, large

What part in Phylum anthrocerophyta is the sporophyte and which is the gametophyte?

The part sticking up is the sporophyte the part in the ground is the gametophyte

Phylum hepatophyta are non-photosynthetic

true

What phylum where the earliest land plants similar to

Phylum Hepatophyta

What phylum is the mosses?

Bryophyta

What is the most diverse clade of the nonvascular plants?

Phylum bryophyta

What are two conditions that Phylum Bryophyta can survive in?

loss of most body water and cold or dry places

Why are mosses ecologically important?

They store 400 billion tons of organic carbon which is important in stabilizing the global atmospheric CO2 concentrations.

What are the dominate plant in the landscape today?

Vascular plants

What was one important trait of early vascular plants?

Branched sporophytes that were not dependent on gametophytes

What did branching allow for in vascular plants?

It allowed for more complex bodies, multiple sporangia per individual plant

What are characteristics of living vascular plants?

1. Life cycle with dominant sporophyte

2. Vascular tissues that transport water and food

3. Presence of roots and leaves

Sporophyte is larger and more complex in vascular plants.

True

The sporophyte in vascular plants is independent of the ____.

gametophyte

Gametophytes in vascular plants are greatly ___ in size.

Reduced

What does the Xylem do in vascular tissues?

It conducts water and minerals. It creates a tracheid cell.

What strengthens the xylem?

Lignin

What does lignin allow the plant to do?

Grow taller

What does phloem do?

Conducts sugars and organic compounds

Sporophylls

Modified leaves with sporangia

Megaspores

Female gametophytes

Microspores

Male gametophytes

Fern and fern allies are a single clade.

False

What are the two extant phyla of seedless vascular plants?

Lycophyta and pterophyta

What are three characteristics of Phylum Lycopods?

Large branched, independent sporophytes

Phylum Lycophyta produce their spores in cone like ___.

Strobilus

Phylum Pterophyta are the?

Ferns and most diverse group

Where are you most likely to find Phylum Pterophyta?

Wet environments

What’s special about the fern life cycle?

They have a bisexual gametophyte and sporangia are housed in sori

What are three characteristics of the fern gametophyte?

1. Bisexual

2. Photosynthetic

3. Very very small

Sporangia produce spores on the sporophyte plants. How are these spores produced and where are they found?

Produced by meiosis and found in clusters call sori

What are 5 characteristics of all seed plants?

1. Production of seeds

2. Reduced size of gametophytes

3. Heterospory

4. Ovules

5. Pollen

What the definition of a seed?

An adaptation for terrestrial plants consisting of an embryo packaged along with a store of food within a resistant coat

Seeds are embryonic ___.

Sporophytes

What was the important evolutionary innovation provided when gametophyte size reduced?

The tiny gametophytes developed from spores that were retained within the sporangia.

Most seedless vascular plants are ____.

Homosporous

Bisexual gametophyte

One type of sporophyll that produces one type of spore

All seed plants are ____.

Heterosporous

Heterosporous

Two types of sporophyll two types of spores

Are megasporangia male or female?

Female

Are microsporangia male or female?

Male

Seed plants are unique in retaining the _____ within the parent sporophyte

megaspore

Ovule contains what three parts?

Megasporangium, megaspore, and integuments

What do microspores develop into?

Pollen grains

Is the male or female gametophyte inside the pollen grain?

Male

Do seed plants need water to disperse sperm?

No

Most gymnosperms and all angiosperms do/do not have flagellated sperm?

Do not

Gymnosperms use what to disperse pollen?

The wind

Angiosperms use what to disperse pollen?

Polinators

Is a seed formed before or after the fertilization of an egg?

After

What does the zygote grow into in a seed?

Sporophyte

A seed is the ….?

Embryo and food supply (endosperm)

What is the seed coat made of?

Integuments

What where the two big advantages to seeds over spores?

Better resistant to harsh environments and better dispersal mechanisms

Gymnosperms are ___ seeds.

Naked

When was the first gymnosperm fossile dated to?

360 MYA

Do gymnosperms have high or low species diversity?

Low