The Protists

Animal-Like Protists

• AKA Protozoa• Heterotrophic• Consume/ingest/eat material from their

surroundings

Type of Protozoans

• Classified according to locomotion

1. Sarcodina (pseudopod)

2. Mastigophora (flagellated)

3. Ciliophora (ciliated)

4. Sporozoa (parasitic)

PeranemaAmoeba

Paramecium

Plasmodium

Sarcodina: Amoeba

• Single celled with no set body shape• Creates temporary projections of cytoplasm

called pseudopods to move and feed• Feed by endocytosis engulfing organisms with

their pseudopods

Mastigophora: Peranema

• Found at the bottom of freshwater bodies• Morphologically similar to Euglena, without

the chloroplasts and eyespot• Captures and consume

live prey with the help of a rigid feeding apparatus called a “rod-organ”

Ciliophora

• Covered with hair like projections called cilia• All these organisms are aquatic• They are the most advanced of the

protozoans, living in both fresh and saltwater

Ciliophora: Paramecium

Feeding

Sporozoa

• Parasitic protozoans• Lack means of independent locomotion• Movements depend entirely on the host’s body fluids• Possess fewer organelles and specialized structures• Able to multiply asexually in animal tissues by

forming haploid reproductive cells, called spores• Spores mature into individuals without fertilization

Sporozoa: Plasmodium

• Causes malaria in humans

• Complex life cycle involves two hosts: humans and mosquitoes• Insects that transmits

sporozoans from one host to the next are called insect vectors

Fungilike Protists• Slime moulds• Prefer cool, shady, and moist places• During some stage of their life cycle, they may

resemble protozoans• At other time, they produce spores like fungi

Fungilike Protist

• Some species converge into a large, slimy plasmodial mass and act like a single organism

• Role in the environment– Like Fungus, slime moulds consume dead organic

matter– Also consume bacteria and fungi

Homework

• Text page 133– Questions: 4, 6, 9, 13