1. Mainly photosynthetic
2. Informally called algae
3. Most members are in the species phytoplankton.

1. Phytoplankton
2. Algae

• Mostly single-celled
• Autotrophic
• Mainly marine - some freshwater
• Microscopic (most)
• Drift with water currents
• Form base of most all aquatic food chains
• (Phytoplankton are algae, but carry these specific characteristics.)

• Larger & most all multi-celled
• Red - Brown - greed algae (seaweed)

[Algae]

Phylum Chlorophyta:

• Green algae
• Ancient group probably gave rise to green plants
• Most like green plants above all others
  • Pigments - chlorphil a
  • Cell wall - cellulose
  • Food reserve - True starch
• Mixture fresh & marine sp.

[Algae]

Phylum Phaenophyta:

• Brown algae
• Live mainly in inner tidle zones of cool & temperate marine waters.
• All multi-celled
• Only a few of the cf 1,500 sp. are fresh water.
• Kelps = largest protistins known [up to 60 meters long]
  • Show a high degree of external differentiation
• Economic value - Agar in/over cells  [used for tooth paste, jello, icecream, gel agar, ect.]

[Algae]

Phylum Rhodophyta:

• Red algae
• Compared to brown; smaller = (largest about 0.7 m long)
• Warm marine waters - very few that are fresh water
• Live in deepest water
  • Pigment they have allows this (catches light, pigment)
• Some take in CaCO₃ into cell walls
• Economic value - Food & Fertilizer

• Most are multi-celled
• Major decomposers
• Heterotrophs
  • Saprobic
  • Parasitic
• Secrete digestive enzymes outside of cell & cells absorb the broken down products. = Extracellular
• Metabolic activities:
  • Release CO₂ into atmosphere
  • Return many simple nutrients to the soil that are absolutely needed by autotrophs (green plants)
• Most common = Fungal hyphae become modified to form a reproductive structure that gives rise to spores = sporangium.
  • Spores give rise to new mycelium.
  • Mycelium -
• # sp. = about 100,000 sp.
• Some fungi are pathogenic

They can lead to:

• Food spoilage
• Disease- chestnut blight
• Ring worms
• Athletes foot
• Rot of Stone fruits
• Poisoning
• Smut & rust of grains.

• Haploid & diploid stages
• Reproduce sexually & asexually by spores. [Not motile spores]
• Spores = Germinate into a new mycelium
• Spores produced in Sporangia = Asexual
• Spores produced in Gametatangia = Sexual

• Known as zygote fungi
  • Form a resistant structure by sexual reproduction called a zygosporangium.
• Mostly terrestrial in soil, but also in decaying matter.
• One group forms mygorhizae.
• Zygomycete hyphae are cenucytic = multinucleus.

[Phylum Zygomycota]

Ex. Rhizopus Stilonifer

• Responsible for food spoilage

• Life cycle:

1.  
   1. Horizontal hypae spread out over food source (bread) - penetrate & absorb nutrients.
   2. In asexual stage: sporangia develop in the tips of the upright hypae.→ Spores develop & are dispearsed in the air. → Land on a new food source & germinate into new hypae (=mycelia).
   3. If environmental conditions deteriate = Reproduce sexually:
      • Mycelia of opposite mating type (+ -; stolons) are identical in appearance, but diff. in chemical markers. → Produce a resistant structure (environmentally) called a zygosporangium (called nuclear fission) → Resistant to freezing & descication.
      • → When conditions improve, zygosporangia release genetically diverse spores that colonize new food.

• SAC Fungi

• Cf. 60,000 sp.
• Produce sexual spores in Sac-like asci in an Ascocarp.
• Asexual = conia → produce conidial spores
• Most are terrestrial, but some are aquatic or marine & fresh water.
• Range in size from unicellular yeasts to large elaborate cup fungi & morals.
• Include some of the most devistating plant pathogens
  • Others are simple saprobs
  • Many live with algae in a mutualistic association called Lichons.
  • Others form myconizae with plants.
  • Others live in plant leaves and help protect leave by releasing toxic compounds (protect from insects)
• Reproductive:
  • Asexual spores - produce lots of asexual spores that are wind dispersed.
    • Produced on specialized conidphoras (conidia = spores)
  • Sexual
    • Form distinctive reproductive structures called ascocorp.

[Phylum Ascomycota]

Yeasts:

• About 500 sp. known.
• Many live in nectar of flowers & in fruits & in leaves of plants.
• CO₂ by-product.
• Ethanol end-product in yeast metabolism.
• Some used in genetic engineering studies.

• Club fungi (common name)

• Largest - # of species
• Includes:
  • Grocery store mushroom
  • Many saparobic types in this phylum
  • Many are symbiants
• General life cycles:
  • Spore producing cells = Basidia (bear sexual spores)
  • Basidia develop on a short-live reproductive structure = Basidiocarp = spores develop on gills.
  • Spores fall off and can germinate into + or - mycelia cells.
  • When hypae of two compatable types (+ -) come together = cytoplasmic fusion (Dikaryotic mycelium)

• Both species (often very disimilar) benefit from each other.

Obligate mutualism- Obligated to each other for survival.

Faculative mutualism- Both can live w/o each other. [They are just better off with each other.]

[Fungi]

[Beneficial Associations]

Lichons:

• Mutualistic association b/w a fungus & cyanobacteria and/or green algae ↔ (single celled species)
• Lichon forms when fungal species penetraits the algeal species w/ its hyphae & holds it.
• Fungal species - absorbs carbohydrates from the host (green algae)
• Algal species = photosynthetic organism suffers in its own growth, but they benefit from the sheltering effect of the fungal species = allows the algal species to live in harsh environments.

[Fungi]

[Beneficial Associations]

Mycorhizae:

• Called a "fungus root."
• Form a mutualism b/w fungal hyphae and young roots of vascular plants (trees)
• Fungus = Absorbs carbohydrates from host plant.
• Plant = Absorbs needed mineral ions from fungus.

• Consists of photoautotrophs:
  • Use chlorophyl a & b
  • Multi-celled
  • Nearly all are terrestrial
• In general, plants are:
  • Structurally adapted to intercept light.
  • Absorb water & minteral ions.
  • Conserve water.
  • Have lignin reinforced tissue that permits upright growth.
  • Root or root-like systems to mine soil for mineral ions and water.
  • Have stomata (tiny passage ways) for taking in CO₂= leaves.
  • Most all have vascular system to conduct water and solutes.

• cf. 295,000 sp. -Most are vascular
• Only 19,000 species are nonvascular = Bryophite → seedless.
• Seedless vascular plants - ferns, horsetails, etc.
• Gymnosperms - cycaids, ginkos, conofers → have seeds
• Angiosperms - Flowers, seeds, - Monocots & Dicots.
• Ancestors of plants probably evolved in seas cf. 700 mya - 400 mya they appeared on land.

• Seedless - Nonvascular

• Includes mosses, liverwarts, hornworts.
• Overall, most grow in fully or seasonally moist habitats.
• Overall, most - small, most less than 20 cm tall
• Most have rhizoids.
  • Attach to soil
  • Serve as absorbitive structures, just like roots.
• Simplest plants to exhibit 3 features seen in all plants:
• Bryophytes ( = 3 phylum) - Gametophites most conspicuous & dominant of life history.
• Spores - germinate into a new gametophyte = most all are male or female.

1. Cuticle that prevents water loss.
2. Cellular jacket or covering around sperm & egg producing parts.
3. Have gametophytes & sporophytes.

• Sphagum sp.

• Wind dispersal of liteweight spores has distributed them across the world.
• They form essential habitats for many small invertibrates.
• <Sphagum is> wet land moss that forms extensive deposits of undecayed organic matter = peat bogs.
• World's peat lands [collectively] store extimate 400 million tons of organic carbon = carbon resevoir plays an important role in stabilizing atmosphere CO₂ concentraition.
• Today = [economically] they are harvested as soil conditioner.

• They grow in low temperatures.
• Release acidic compounds when die.
• Quick burial and cut off from oxygen.

• Includes Whisk ferns, lycophytes, horsetails, ferns (pteridophytes).
• How they differ from bryophytes:
  • Vascular
  • Sporophyte not attached to gametophyte.
  • Sporophyte is dominant part of life cycle.

[Seed-Bearing Vascular Plants]

Gymnosperms:

• No flowers.
• Best known group are the conifers. Phylum coniferophyta.
  • Includes: Rines, furs, spruces, junipers, redwoods, some shrubs, etc.
  • Most all are evergreen.
  • Have: Needle-like or scale like leaves.
  • Cones = clusters of modified leaves [reproduction]
  • Heterospores=
    • Microspores = from male cones (pollen) - small cones
    • Megaspores = female cones, develop into female gametophyte

Pollen - grains drift off of the male cone, → some land on ovules of female cone = pollination → seed - germinate into new sporophyte.

[Seed-Bearing Vascular Plants]

Angiosperms:

• Flowering, seed-bearing plants ... Vascular

• Only angiosperms produce flowers
• Many coevolved w/ pollenator.
• At least 260,000 sp. - size: few mm upto 100+ meters
• Are a few that are not photosynthetic = parasytic.
• Most successful plants in terms of diversity, numbers, and distribution.
• Two major classes:
  
  • Monocots: cf. 80,000 sp.
  • Dicots: cf. 180,000 sp.

[Seed-Bearing Vascular Plants]

[Angiosperms]

Monocot:

• One leaf startout.
• Root zylum, formed in ring.
• Vascular bundles various.
• Flower part in 3's or multiples of 3's

[Seed-Bearing Vascular Plants]

[Angiosperms]

Dicot:

• Two leaf startout.
• Root zylum in a cross (x).
• Vascular bundles in strict ring.
• Flower parts in 4's or 5's or multiples of 4's or 5's.