Through symbiosis

(large prokaryotic cell engulfed smaller bacterial cells that began to live and reproduce inside prokaryotic cell rather than being destroyed)

First primative cell was probably single-celled and independent. Eventually formed colonies that became specialized and evolved into multicellular organisms.

Fungi

Algae

Helminths

(have unicellular eggs or larval forms)

10x thicker

Structurally more complex

Covered by an extension of the cell membrane

9+2 arrangement (9 outside, 2 in middle)

Whip-like movement

(not runs and tumbles)

Shorter locomotor appendages that are more numerous.

Also function as feeding and filtering structures

Appears as network of fibers, a slime layer, or a capsule.

They both function as protection, adhesion, and reception of signals.

Fungi and most algae have a thick, rigid cell wall

Protozoa and animal cells do not have a cell wall

Thick inner layer of chitin or cellulose

Thin outer layer of mixed glycans

1. Divide independently of the cell
2. Contain DNA
3. Contain prokaryotic-sized 70S ribosomes

• Convert energy of sunlight into chemical energy through photosynthesis
• Contain chlorophyll and have own DNA and 70S ribosomes

80S

We can use drugs to affect 70S ribosomes of prokaryotic cells without affecting 80S ribosomes of eukaryotic cells. The drugs would however affect the ribosomes of the mitochondria and the chloroplasts of eukaryotic cells.

1. Macroscopic (mushrooms, puffballs)
2. Microscopic (molds, yeasts)

Hyphae- long, threadlike cells

Septate (segmented surface) or nonseptate (smooth surface)

All fungi are heterotrophic.

True or False?

Few fungi are saprobes.

True or False?

Few fungi are parasites.

True or False?

Cryptococcus

Candida

Spores

1. Sporangiospores: formed by successive cleavages within a saclike head called a sporangium. Spores are released when sporangium ruptures.
2. Conidiospores (Conidia): free spores not enclosed by a sac. They develop either by pinching off a fertile hypha or by segmentation of a preexisting hypha

Sexual spores are produced by most fungi at some point.

True or False?

• any unicellular or colonial organism that lacks true tissues
• algae and protozoa

Algae contain all eukaryotic organelles.

True or False?

Algae are one of the main components of plankton.

True or false?

1. Ectoplasm: clear outer layer involved in locomotion, feeding, and protection
2. Endoplasm: granular inner region house the nucleus, mitochondria, and food/contractile vacuoles

Some protozoa have organelles that work like a primitive nervous system.

True or false?

• Some have special feeing structures (oral grooves)
• Some absorb food directly through cell membrane
• Parasitic species live on the fluids of their host or can actively feed on tissue

fresh and marine water

soil

plants

animals

**main limiting factor is the availability of water**

• Pseudopods (false foot)- amoeboid motion
• Flagella- one to several; some attached along the length of the cell by the undulating membrane
• Cilia- mostly distributed over entire surface of the cell

All protozoa reproduce by asexual methods.

True or False?

1. Mastigophora (flagellated)
2. Sarcodina (amoebas)
3. Ciliophora (ciliated)
4. Apicomplexa (sporozoa)

• motility primarily by flagella
• single nucleus
• parasitic forms tend to lack mitochondria and Gogli apparatus
• Most form cysts and are free-living

1. Trypanosoma: sleeping sickness (T. brucei) and Chagas disease (T. cruzi)
2. Leishmania: blood pathogens carried by insect vectors
3. Giardia: intestinal parasite spread in water contaminated with feces
4. Trichomonas: parasite of the reproductive tract of humans spread by sexual contact

• pseudopods
• some have flagellated reproductive states
• mostly uninucleate
• usually encyst
• most free-living and not infectious

Entamoeba

• Amoebiasis caused by Entamoeba histolytica
• 4th most common protozoan infection in the world
• AKA amoebic dysentery

• Trophozoites mobile by cilia
• some have cilia in tufts for feeding and attachment
• most develop cysts
• most have definite mouth and feeding organelle
• show relatively advanced behavior
• majority are free-living and harmless

• Most not motile
• Complex life cycles
• Produce sporozoites following sexual reproduction
• Most form oocysts
• ***Entire group is parasitic***

• Plasmodium (malaria)
• Toxoplasma gondii (toxoplasmosis)

Tapeworms, flatworms, roundworms

Microscope is necessary to ID eggs and larvae

Thin and often segmented.

In the phylum Platyhelminthes

Asexual or sexual reproduction.

• Cestodes (tapeworms)- long, ribbonlike
• Trematodes (flukes)- flat, ovoid bodies

AKA nematodes

elongated and cylindrical

unsegmented

phylum Aschelminthes

Most developed organ are those of the reproductive tract

Some degree of reduction in digestive, excretory, nervous, and muscular systems

Most have thick cuticles for protection and mouth glands for break down the host's tissue

1. Person swallows egg (direct contact or by touching articles touched by an infected person)
2. Eggs hatch in intestine
3. Release larvae that mature into adult worms (1 month)
4. Male and female worms mate
5. Female migrates out of anuse to deposit eggs (causes intense itching- scratching contaminates fingers which transfer the eggs)
6. Eggs spread to others or the host reinfects himself