Unicellular Organisms Learning Intention: Describe the general structure of unicellular organisms and the functions of cellular components and organelles.

General Characteristics 1. Eye spot- a spot that acts as a light receptor (sensor) 2. Contractile Vacuole- organelle that holds excess fluids. It periodically empties this into the cytoplasm. This forces water out of the cell

General Characteristics 3. Cilia – small hair like projections. Many extend from a cell. Single celled organisms use them for movement. They beat in one direction 4. Flagellum – very much like cilia, but are long and there are only a few per cell. Also used for movement 47l2nbDQ =Ey7Emmddf7Y

General Characteristics 5. Oral groove- Used to take up food. Cilia beat food particles toward oral groove

Amoeba  Food vacuole  Contractile vacuole  Nucleus zJ_pA

Euglena  Contractile vacuole  Chloroplast  Nucleus  Flagellum  Whip like structure used for propulsion  Eyespot  Light sensitive pigment shield. Allows organism to respond to light. 2Ij4

Paramecium  Food vacuole  Nucleus  Oral groove  Funnel shaped groove food passes along to reach cell mouth  Anal pore  Specialised region of plasma membrane where undigested contents of food vacuoles is released