Background: 

Ciliates are single celled organisms that all have cilia. Most have two nuclei, which is not common among single celled organisms. Their form of sexual reproduction is referred to as conjugation, where they exchange their nuclear material with the other. The ciliates differ from each other through the arrangement and location of cilia, and their cell shape, size, color, and movement.

Purpose:

The purpose of this experiment is to utilize the dissecting microscopes to view six unknown ciliates in order to identify all six ciliates and their defining characteristics. It is important to understand the defining characteristics of each ciliate because these characteristics also determine the function of certain parts of ciliates. This experiment will prepare us to be able to identify ciliates in later soil samples that we collect.

Procedure:

1- clean desk with bleach cleaning solution in order to kill of contaminants that could make results vary

2-obtain a clean well plate

3-use plastics pipette to place each unknown ciliate into separate wells

-make sure to note which number of the unknowns went into which well

-fill wells half full with the liquid containing the ciliates

-keep each unknown pure: don’t use pipette associated with unknown #1 to place unknown #6 in a well

4-observe each group underneath the dissecting microscope and record in the table provided

5-use details in each observation

6-sketch each ciliate

7-compare these results to images and information about known ciliates to provide identification and reasonings for the six ciliates in your wells

Table: Characteristics of Six Unknown Ciliates

Unknown #1:

Shape: oval, skinny

Size: very small, hard to see: smallest

Movement: swimming, wavy/spiral motion

Location: on the surface/right under the surface; stayed towards center of the well

Unknown #2:

Shape: fat, rounded square

Size: bigger than unknown #1 but not by much, fatter than #1

Movement: crawling, jagged motion

Location: right below the surface, cling to side of the well, grouped together

Unknown #3:

Shape: oval, sea-snail shaped

Size: similar in size to unknown #1

Movement: spiral motion, swims fast

Location: all levels, moves in singles, everywhere in the well

Unknown #4:

Shape: slug-shape, skinny at top and fat at the bottom

Size: medium sized, bigger than #1 but smaller than #6

Movement: slow and crawling

Location: middle level, random locations all over wells, scattered, many

Unknown #5:

Shape: long and skinny

Size: longer, double size of unknown #1

Movement: worm-like, slow, smooth motion

Location: bottom of well, single or in twos, stayed by sides of wells

Unknown #6:

Shape: rain drop/trumpet shaped

Size: larger then unknown #2

Movement: spiral motion, swimming

Location: all levels, singular

Sketch:

file:///var/folders/8g/bpg4rmgs43b08zs_17spz3m40000gn/T/com.apple.iChat/Messages/Transfers/IMG_4591.jpeg

Comparisons:

Unknown #1: Paramecium 100-200μm

-ovoid/cigar-shaped. Prominent oral groove, underlying oral aperture less obvious. Two contractile vacuoles. Quick spiraling swimming. Prominent trichocysts. Feeds on bacteria. Common in sediments.

Unknown #2: Euplotes 20-150μm

-a hypotrich ciliate. rigid, ovoid to rectangular. Dorso-ventrally flattened with dorsal ridges. Prominent ventral cirri in groups and uses cirri to walk on surfaces. jerky motion. prominent macronucleus (c-shaped). sometimes planktonic.

Unknown #3: Paramecium 100-200μm

-ovoid/cigar-shaped. Prominent oral groove, underlying oral aperture less obvious. Two contractile vacuoles. Quick spiraling swimming. Prominent trichocysts. Feeds on bacteria. Common in sediments. Same species and unknown #1 but different variation

Unknown #4: Blepharism 50-350μm

-pink or red cells with the contractile vacuoles at the posterior end. well-developed undulating membrane alongside the adoral zone of the membranelles

Unknown #5: Spriostomum 200-300μm

-elongated, narrow, and contractile. single large contractile vacuole at posterior end, with long collecting channel running anteriorly. feed on bacteria and small algae

Unknown #6: Stentor 150-3000μm

-large and contractile. trumpet shaped when extended, bell shaped when contracted. attached to plant surfaces/free swimming. AZM spirals clockwise. color is commonly turquoise, pink, and black