Chapter 18: Protista

How many years ago were organisms confined to oceans?

Less than 1 billion years ago

What type of environmental factors are organisms confined to oceans usually protected from?

Drying out, ultraviolet radiation, and large fluctuations in temperature

How many years ago did green algae begin to transition from water to land?

About 400 million years ago

What did the green algae transition from water to land give rise to?

Green plants

What is most likely an indirect ancestor of land plants?

Coleochaete

Which specific features of Coleochaete cells are shared with/similar to those of land plants?

Cells that resemble parenchyma, development of cell plate, and phragmoplast during mitosis

What type of covering does a Coleochaete contain that is similar/shared feature to land plants?

A protective covering for zygote

What kind of compound do both Coleochaete’s and land plants produce?

Ligin-like compound

What type of cells do all members of the Domain Eukarya contain?

Eukaryotic cells

Which kingdoms are included in the Domain Eukarya?

Protista, Plantae, Fungi, Animalia

What do organisms in Protista vary from?

Unicellular to multicellular

The organisms in Protista are considered “nutrition varied” due to their:

Photosynthetic organisms, ingestion and absorption of food

How are the individual life cycles of organisms in Protista?

Varied considerably

How does reproduction of Organisms in Protista generally occur?

By cell division and sexual processes

What are examples of algae?

Seaweed, some pond scum’s, fish-tank films, colored patches in swimming pools

Which kingdom contains algae?

Kingdom Protista

In Kingdom Protista, algae are grouped into several phyla based on:

Form of reproductive cells, and combinations of pigments and food reserves

What type of algae is the Phylum Chlorophyta?

the Green Algea

Where are the greatest variety of Phlyum Chlorophyta usually found?

In freshwater lakes, ponds, and streams

Where can Phylum Chlorophyta (green algae) also be found?

Tree bark, animal fur, snow banks, flatworms or sponges, on rocks, in linchen “partnerships”

Which two types of chlorophyll does Phlyum Chlorophyta have?

Chlorophylls a and b

What does Phlyum Chlorophyta store food as?

As starch

How many nucleuses do most Phylum Chlorophyta cells have?

A single nucleus per cell

How do most Phlyum Chlorophyta reproduce?

Both sexually and asexually

Where do Chlamydomonas commonly inhabit?

Freshwater pools

Are Clamydomonas cellular or unicellular?

Unicellular

Which pair of characteristics in a Chlamydomonas allow the cell to be pulled through water?

A pair of whip-like flagella on one end

How many vacuoles are located at the base of a flagella in a Chlamydomonas?

Two or more vacuoles

What do the vacuoles inside of a Chlamydomonas regulate?

Water content of a cell, which removes waste

Which type of chloroplast does a Chlamydomonas contain?

A single, cup-shaped with one or two pyrenoids inside

What type of structures are Pyrenoids?

Proteinaceous structures associated with synthesis of starch

What type of eyespot is located at the near base of the flagella in a Chlamydomonas?

Red eyespot

What does the red eyespot inside of a Chlamydomonas allow for?

Alga to swim toward light

What is the nucleus divided by in Chlamydomonas asexual production?

By mitosis

What do cell contents of a Chlamydomonas become during asexual reproduction?

Two daughter cells within cellulose wall

What do the daughter cells pride do during Chlamydomonas asexual reproduction develop?

Flagella to swim away

What do all cells remain after Chlamydomonas asexual reproduction, which means no change in chromosome number?

Haploid

Where does Meiosis occur during Chlamydomonas asexual reproduction?

Zygospore

How many haploid zoospores are produced from Meiosis during Chlamydomonas asexual reproduction?

4 haploid zoospores that grow into full-sized algae

How many cells fuse together to form zygote during Chlamydomonas asexual reproduction?

Two cells

What does the formation of zygote during Chlamydomonas asexual reproduction eventually become?

Zygospore that may remain dormant

Ulothrix

Filamentous with holdfast cells at one end

What is the structure of the chloroplast in an Ulothrix?

Wide, curved, somewhat flattened, with one to several pyrenoids

What occurs in the cells contents during Ulothrix asexual reproduction?

Condense, divide by mitosis, and become zoospores inside parent cell

Where do zoospores escape from a parent cell?

A pore in parent cell wall

What kind of cells do zoospores in Ulothrix resemble?

Chlamydomonas cells

What do zoospores in Ulothrix eventually grow into?

New filaments

What happens to the cell contents during the life cycle of Ulothrix?

Condense and divide by mitosis inside parent cell

What does each new cell produce during the life circle of Ulothrix?

Flagella

What do cells become after escaping from parent cell during the life cycle of Ulothrix?

Gametes

What kind of cells are Spirogyra (Watersilk) filaments of?

Cylindrical cells

Where does Spirogyra frequently float in?

Masses on surface of quiet freshwater

What is the structure of the chloroplast located inside of the Spriogyra?

Ribbon-shaped and spirally wrapped around vacuole with pyrenoids at regular intervals

How does Spirogyra sexually reproduce?

By conjugation

What is fused together to form conjugation tubes during Spirogyra sexual reproduction?

Papillae

Where does the condensed protoplast of a filament flow through during Spirogyra sexual reproduction?

A tube to adjacent cell

What is fused together to form zygotes during Spirogyra sexual reproduction?

Protoplasts, which develops a thick wall

What do zygotes eventually undergo during Spirogyra sexual reproduction?

Meiosis

Oedogonium

Epiphytic filamentous green alga with holdfast

What is the structure of the chloroplast located inside of Oedogonium?

Large, netlike with pyrenoids at intersections of net

How does Oedogonium aesexually reproduce?

By fragmentation, or zoospores

How are zoospores produced during Oedogonium aesexual reproduction?

Singly in cells at tips of filaments

What do the zoospores inside of Oedogonium contain that form fringe toward one end?

About 120 flagella

In oogamy, the two gametes are:

One gamete is motile, while other is largess and stationary

What type of cell is Antheridium?

A box-like cell that produces two motile sperm

What type of cell is Oogonium?

Swollen cell containing a single egg

Where does the sperm enter oogonium through during Oedogonium sexual reproduction?

Through pore

What does a zygote form during Oedogonium sexual reproduction?

Thick walls, remaining dormant

How many zoospores does a zygote produce by meiosis during Oedogonium sexual reproduction?

4 zoospores that grow into new haploid filaments

How does Spirogyra reproduce asexually?

By fragmentation of filament

What type of algae is Chlorella?

A widespread alga composed of tiny spherical cells

How does Chlorella reproduce asexually through the process of mitosis?

By the formation of daughter cells or auto spores

What is Chlorella used in?

Research, food source

What type of algae is Desmids?

Mostly free-floating and unicellular

How do Desmids reproduce?

By conjugation

What is the structure of Hydrodictyon (Water Nets)?

Net-like, tubular colonies with hexagonal or polygonal meshes

How do Hydrodictyon reproduce?

Aesexual reproduction, isogamous sexual reproduction

Isogamous

Two flagellated gametes

What type of cells does Acetabularia (Mermaid’s Wineglass) consist of?

A single, huge cells shaped like a delicate mushroom

What is Acetabularia used in classic experiments to demonstrate?

Influence of nucleus on form of cell

Volvox

A colonial green algae held together in a secretion of gelatinous material

How do Volvox reproduce?

Sexual or asexual reproduction

Where are smaller daughter colonies formed in a Volvox?

Inside parent colony

Ulva (Sea Lettuce)

Multicellular seaweed with flattened green blades and nasal holdfast

What is the Ulva’s holdfast used to anchor?

Blades to rocks

What type of a blades does an Ulva contain?

Haploid and diploid blades

What do diploid blades on an Ulva produce?

Spores that develop into haploid blades

What do the haploid blades on Ulva bear that forms gametes?

Gamtangia

What is fused together to form zygotes that grow into diploid blades?

Gametes

How is isomorphism exhibited in Ulva leaves and their blades?

Haploid and diploid blades indistinguishable

Cladophora

A branched, filamentous green alga

Where may Chladophors species live in?

Fresh or marine water

What is the difference between the cells of Cladophora and other green algae?

The cells and its relatives are mostly multinucleate

What kind of colored algae is Xanthophyceae?

Yellow-green algae

What is Xanthophyceae mostly representative of?

Freshwater, a few marine and terrestrial representatives

In which direction are the two flagella of mobile cells oriented in Xanthophyceae?

In opposite directions

What is the type of brown pigment only present in Vaucheria?

Fucoxanthin

How common is sexual reproduction in Xanthophyxeae?

Relatively rare, but does occur

What type of species is Vaucheria?

A oogamous, coencyctic, filamentous species

What is formed during asexual production in Vaucheria?

Aplanospores