Figure 1 Background Information to the phylum Arthropoda and appears to not have changed for

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1 Artemia salina Figure Background Information Artemia salina belongs to the phylum Arthropoda and appears to not have changed for the last 00 million years. Most people refer to them as brine shrimp or sea monkeys. Artemia s segmented body has a pair of jointed appendages on each individual segment. Artemia has a head, thorax, and abdomen region. When increasing in size, Artemia must molt it s exoskeleton about every to days. Very few crustaceans can live in waters that have more salt content than the sea, but Artemia is the most successful. Artemia live in salt lakes and are very rarely found in the open sea. In North America, the Great Salt Lake in Utah has the highest population of Artemia. High concentrations of salt will give the Artemia a red appearance on their exoskeleton. Females grow slightly larger than male Artemia. To distinguish, females have two large lateral egg sacs while males have overdeveloped antennae (Figure ). The eggs of Artemia hatch into free-living larvae and will continue to grow through a molting process until they reach the average adult stage with at least 0 segments. In this lab, you will investigate how the hatching rate is affected by temperature and salinity. Hypothesis MATERIALS Document Camera/Underwater Camera Electronic Balance Personal Computer Interactive White Board/Projector Artemia salina Brine Shrimp Eggs Thermometer or Temperature Gauge Liquifry (food source) Hydrometer Flexible Tubing (0ft) Dechlorinating Agent

2 Aquariums or Large Clear Beakers/Jars Air Pump Seawater (saltwater) PROCEDURE Activity Temperature & Hatching Rates. Place the Artemia salina eggs in each aquarium.. Set up the document cameras on the eggs in each aquarium.. Open the computer and choose to time-lapse record.. Choose the frames per second and start recording.. Once hatching is complete; stop recording. a. The eggs at 0 C should hatch after hours. b. The eggs at 0 C should hatch after 0 hours. c. The eggs at C will probably not hatch after 00 hours; however, these eggs are still viable. To show the students that they will hatch raise the temperature to about C and the hatching should occur. 6. Record your observations in a data table. 7. Save any images or time-lapse recordings to use later in the lab report. Activity Salt Concentration & Hatching Rates Each group will be assigned a numbered glass beaker.. Fill the beaker with 00mL tap water.. Find your numbered beaker in the table below and weigh the salt to add in your beaker. Beaker Salt (grams) 0

3 For each beaker, weigh and place grams of Artemia salina.. Cover each beaker with plastic to inhibit the evaporation of the water.. Set the beakers in a well-lit area so they all have equal amounts of light. 6. Set up the document camera on the eggs in your assigned beaker. 7. Open the computer and choose to time-lapse record. 8. Choose the frames per second and start recording. 9. Once hatching is complete; stop recording. 0. Record your observations in a data table and share data with whole class.. Save any images or time-lapse recordings to use later in the lab report. QUESTIONS Activity. Dependent Variables (DV): a. How do you keep these variables constant?. Independent Variable (IV):. Predict the effect of the IV on the DV:

4 . How will you measuree the outcome of your experiment? Activity. Dependent Variables (DV): a. How do you keep these variables constant?. Independent Variable (IV):. Predict the effect of the IV on the DV:. How will you measuree the outcome of your experiment?. What would happen to the hatching rate of Artemia if you increased the temperature? a. If it decreased?? 6. What would happen to the hatching rate of Artemia if you increased salinity?

5 7. If it decreased? 8. Under what conditions would be the best environment for hatching Artemia?