1. There is a secret within every drop of water in a lake, pond, or stream.
Pond Water Video

2. Prokaryotes vs. Eukaryotes
Prokaryotes: a single-celled organism that lacks a membrane-bound nucleus.
-DNA is in cytoplasm
-Ex: bacteria
Eukaryotes: any organism whose cells contain a membrane-bound nucleus, which contains its DNA.
-Ex: Plants, Animals, Protists

3. Kingdom Protista (Protists)
PROTISTS: any member of the kingdom Protista, a group of eukaryotic, mostly unicellular microscopic organisms.
“Trash can” kingdom
(not plants, animals, or fungi)
Very diverse group

4. Characteristics of ALL Protists
All protists have a membrane-bound nucleus (“control center” within the cell).
All protists contain other organelles (membrane- bound structures within a cell that perform specific jobs)

5. Characteristics of MOST Protists
-Most live in wet places (oceans, lakes, swamps, damp soils.)
-Most are unicellular (made of one cell).
-Most have structures that help them move.

6. How do protists get energy?
Autotrophs = get energy from the sun through photosynthesis.
Heterotrophs = get energy by eating other organisms or by decomposing material.
Mixotrophs = can get energy from the sun AND by eating other organisms (“mixing it up”).
How do you think this green Volvox gets its energy?

7. AMOEBA
-Microscopic (small), unicellular (one cell) protozoa (animal-like protist)
-Live in fresh water, salt water, in soil, and as parasites in moist body parts of animals.

8. Structures of an Amoeba
-Plasma membrane: surrounds cell, allows substances to pass in/out
-Nucleus: membrane-bound control center
-Food vacuole: digests food
-Cytoplasm: jelly-like substance within cell
-Contractile vacuole: pumps water out of cell

9. Amoeba Movement & Feeding
Pseudopodia: extensions of the cytoplasm that allows amoebas to move and detect food; “false feet.” Also called cytoplasmic streaming.
Amoeba Eats!

10. Amoeba Reproduction
Amoebas reproduce by a type of asexual reproduction (1 parent) called binary fission.
= DNA is replicated and cytoplasm pinches in half to produce 2 identical daughter cells.

11. PARAMECIUM
Paramecium is a microscopic (very small), unicellular (one cell) protozoa (animal-like protist).
It is plentiful in freshwater ponds.

12. STRUCTURES OF A PARAMECIUM
Pellicle: Thick membrane that gives the paramecium its shape
Nucleus: “control center”
Cytoplasm: jelly-like substance that hold all the organelles
Cilia: hair-like projections that help it move
STRUCTURES OF A PARAMECIUM

13. 5. Contractile vacuole: Remove excess water out of the cell; works
like a pump.
Cilia
Pellicle
Macronucleus
Micronucleus
6. Oral groove: takes in food
Contractile vacuole
8. Food vacuole: digests food
Oral groove
Food vacuole
Anal pore
9. Anal pore: Removes waste
Trichocyst
10. Trichocyst: Protection or defense against predators

14. Paramecium Movement
The outer surface of the cell is covered with many hundreds of tiny hair-like structures called cilia.
Act like “microscopic oars”
Can swim backwards, forwards, or rotate using the cilia.
Moves so quickly that we have to add a thickening agent or quieting solution to the slide to slow it down to study it.

15. Paramecium Feeding
The paramecium rotates on its axis as it moves through the water.
Small particles of debris and food are collected and swept into the oral groove (6) and down the funnel-shaped gullet (7) by the cilia that also helps it move.
Eats small organisms such as bacteria, yeasts, algae and even other smaller protozoa.

16. Paramecium Reproduction
Paramecium reproduce by conjugation and binary fission.
Conjugation: 2 paramecia exchange nuclear material and then separate.
Binary fission: cell replicates its DNA, cytoplasm pinches in half, and 2 new daughter cells are formed (cell then grows in size and makes structures).

17. Paramecium Excretion
Food waste left in a food vacuole is excreted through the anal pore (the vacuole and pore fuse.
Other wastes left over from cellular activity (metabolic waste) simply diffuse through the pellicle.
Excess water and some metabolic wastes are excreted through the contractile vacuole.

18. “One scientist calculated that if all the
progeny of a single Paramecium
survived, assuming a division rate of
once a day, then after 113 days, the
mass of paramecia would equal the
volume of the Earth! “