Lecture 11 Algae

Oxygenic Photosynthetic protists that do photosynthesis via primary or secondary endosymbiosis.

• Primary production of O2 on earth

• 30% by algae

• 20% by prokaryotes (cyano)

• 50% by land plants

What are Algae?

Algal blooms are places in water bodies where the growth of algae is excessive, those places often have chemical contamination which in turn decreases oxygen levels and causes lots of harm to aquatic life.

• Definitions

• Classification

• Food

• What are some examples of what it can do and connections to their various supergroups

  • Red tide (Alveolites (SAR)) cause by: photoautotroph dinoflagellates

What are Haptophytes

• Definition: Unclassified, marine unicellular organism

• What is the classification

  • Eukarya

• Physicals

  • 2 flagella (movement)

  • Haptonema (prey and surface attachment)

• What is it food?

  • photoautotrophs and sometime mixotrophs

• What is it capable of doing?

  • Their dead bodies make haptophytes (hard calcified scale

What are Stramenopiles?

• Definition: straw hair, fine hairlike projections,

• What is its classification?

• Physicals

  • 1 flagella

• What is its food source?

• What are some examples?

  • Diatoms

• What is it capable of doing.

  • Forensics

• Brown algae

  • Multicellular photoautotrophic

  • Plant like reproduction cycle

Explain the sexual reproduction cycle

Human example

What is Alternation of generation

• The production of gametes in algae involves both haploid and diploid stages, where the organism alternates between these phases throughout its life cycle.

• Sporophytes:

  • diploid

  • make spores using meiosis, which results in the formation of

  • haploid spores that can grow into gametophytes.

• Gametophytes

  • haploid

  • produce gametes through mitosis, leading to fertilization and the formation of a new sporophyte generation

• 

Archaeplastida

Definition:

• Direct ancestors of primary Endosymiosis

• The source organism of secondary endosymbiosis, which led to the evolution of red and green algae, as well as land plants.

Green Algae

• Paraphylectic group (a grouping that excludes some members)

• Missing embryophytes

• What are the two types of algae

  • Chlorophytes

    • sister group to streptophyta (charophytes +plants)

  • Charophytes (closest relative to land plants)

    • Relations to plants include

    • Morphological traits

    • Molecular phylogeny of nuclear

    • Mitochondrial and plastid DNA

  • Things they have in common,

    • Flagellated sperm

    • Both synthesize cell wall using ring-like protein structure, embedded in plasma membrane (Create their cell wall in a similar manner.

    • Chloroplast DNA, Mitochondria and Nuclear

    • Sporopollenin

      • A though layer which surrounds charophytes zygotes to keep moisture in.

      • This allowed them to live on land

      • Encase plant Spore !!

      • Encases charophytes Zygotes!!