Lecture #6

Question 1

What are the 3 different types of reproduction?

Answer 1

1. Zygotic Meiosis
2. Gamtetic Meiosis
3. Sporic meiosis

Question 2

What is Zygotic Meiosis?

Answer 2

Zygote immediately goes through meiosis to produce haploid cells

Question 3

What is Gametic Meiosis?

Answer 3

Cell undergoes meiosis to produce male/female gametes

-always diploid

Question 4

What is Sporic Meiosis?

Answer 4

Cell undergoes meiosis to produce haploid spores. Spores go on to produce haploid individual which get fertilized into zygotes. Zygotes transform into a diploid sporophyte

Question 5

In sporic meiosis can the haploid and diploid phases look the same?

Answer 5

Yes they can but they do not always

Question 6

What do pollen and seeds have in common?

Answer 6

They are both gametophytes and they eventually give rise to an egg

Question 7

What is haploid?

Answer 7

Zygotic

-Meiosis immediately follows formation the diploid zygote

Question 8

What is diploid?

Answer 8

Gametic

• meiosis occurs in single cells of diploid individuals
• long after zygote formation
• delayed meiosis

Question 9

What is Alteration of generations?

Answer 9

Sporic: both diploid and haploid phases

• meiosis ocas in single cells of diploid individuals
• long after zygote formation
• Meiosis produces spores tp form haploid individuals
• delayed production of gametes

Question 10

Are algae monophyletic?

Answer 10

NOPE

Question 11

What are the 5 characteristics that algae lack which separates them from land plants?

Answer 11

1. Protective layer surrounding gametangia
2. Retention of Zygote and no developing sporophyte within the female gametophyte= archegonia
3. Multicellular diploid sporophyte
4. Multicellular sporangia (capsule) with protective laser of sterile cells
5. Drying and decay resistant spores

Question 12

What is Sporopollenin?

Answer 12

Helps preserve and repeal microbes from degradation and also prevents drying out

Question 13

Are algae unicellular or multicellular?

Answer 13

They can be both

• most unicellular ones are palnktonic
• most multicellular ones are anchored in some way (seaweed)

Question 14

What type of algae would we most likely see in freshwater?

Answer 14

Green

Blue/Green

Question 15

Why were some early eukaryotes photosynthetic?

Answer 15

because they swallowed a bacteria that became incorporated into their system

Question 16

How did the branch of eukaryotic life ‘Excavites’ become photosynthetic?

Answer 16

Somewhere down the line someone swallowed a green algae

-they were not photosynthetic before endosymbiosis

Question 17

Most photoautotrophs are…?

Answer 17

Monophyletic

-ancestral plant lineage took up a cyanobacteria via secondary endosymbiosis

Question 18

Characteristics of Euglenophyta

Answer 18

• Have no walls, but protein strips (flexible)
• Some photosynthetic
• Chloroplasts derived from endosymbiosis with green algae
• Asexual
• 1 long flagellum

Question 19

Characteristics of Cryptophyta

Answer 19

• Chloroplast has 4 membranes (endosymbiosis of photosynthetic eukaryotes; pros red algae)
• Freshwater and marine habitats
• Mostly asexual
• Can take up organic matter and digest it

Question 20

Characteristics of Haptophyta

Answer 20

• not a lot of them, very small
• produce toxic algal blooms
• some can combat global warming: carbon sinks; take it down to the bottom of the ocean when they die
• Form Sulfuric compounds that increase cloud cover; may cool atmosphere
• Heteromorphic alteration of generations (some); the 2 phases look different

Question 21

Characteristics of Dinophyta

Answer 21

• Terrible plants because they produce toxic algal blooms
• Unicellular with 2 flagella
• Many are heterotrophs
• Endosymbionts of coral= zooxanthellae
• Reproduction can either be sexual or asexual

Question 22

Characteristics of Diatoms

Answer 22

• Cell walls made of silica
• Most are photoautotrophs
• Sexual reproduction by gametic meiosis
• Diploid

Question 23

Characteristics of Chrysophyta (Golden algae)

Answer 23

• Phytoplankton in marine and freshwater habitats
• Hetero and photoautotrophs
• Asexual with zygotic meiosis
• Fucoxanthem=golden colour

Question 24

Characteristics of Phaeophyta (Brown Algae)

Answer 24

• Produces the biggest seaweeds
• Mostly marine, provides lots of habitats
• In foods and coating on paper
• Sporic and gametic meiosis

Question 25

Characteristics of Rhodophyta (red algae)

Answer 25

• Most are marine seaweeds
• Some are coralline
• Alteration of generations
• Dulse and nori
• Used in foods, drugs, industrial

Question 26

Characteristics of Chlorophyta (Green algae)

Answer 26

• Closest things to land plants
• They aren’t always green
• Has the most species
• Photosynthetic

Question 27

Which group are land plants derived from?

Answer 27

Chlorophyta

Question 28

What are the 3 group of green algae studied with examples of each group?

Answer 28

1. Chlorophyceae: Chlammy, volvox
2. Ulvophyceae: Ulva
3. Charophyceae: Spirogyra, Chara

Question 29

Which group has the closest existing organism to the probable ancestor of land plants?

Answer 29

Charophyceae

-charales or coleochaete

Question 30

Can green algae have sprout or zygotic meiosis?

Answer 30

Both

• sporic (Ulva)
• Zygotic (Chlamy)