Name _________________________________________
Activity: Got Algae?
1. To examine a variety of seaweeds/algae used as foods.
2. To investigate common household products for the presence of seaweed
Background Information: Although fish and other seafood products make delicious
and healthy meals for people around the world, many American children would not
object if they never had to eat another tuna casserole again. However, they probably
would object if suddenly there was no more cheese, chocolate milk, peanut butter,
pudding, frozen desserts, or fruit drinks. What could so many different types of food
products have in common? These are just a few food products that contain algae or
Many kinds of seaweed are eaten by people because they are full of vitamins
and iodine. Asian cultures use seaweed like green beans and carrots are used in the
United States. However, because Americans have not developed a taste for seaweed,
manufacturers use derivatives from seaweed in our foods. These derivatives –
including alginates, carrageenan, and beta carotene – act as stabilizers, thickeners, and
colorants in the foods we eat on a daily basis. Carrageenan is a generic term for
compounds extracted from species of red algae used in gelling foods, cosmetics,
pharmaceuticals, and industrial products. Alginates are extracted from brown algae and
are used to make water-based products thicker, creamier, and last longer. From green
algae, a natural pigment, beta carotene, is removed and used as a yellow-orange food
coloring. It is currently believed to help prevent certain forms of cancer. (This
information is from
Rotate through the various stations that follow and complete the indicated activity
described for each station.
Station 1: Algae in Your Food
1. Read the ingredient labels for each food product at your lab station.
2. In the table provided, indicate with an X whether each product contains any
seaweed derivatives – carrageenan, alginate, or beta carotene. There may be
more than one derivative present in each food.
Beta Carotene
Station 2: Slideshow: Got Algae?
Open PowerPoint>groups on homeshare>all students> Got Algae and complete the
statements below as you view the slideshow.
1. ____________________ are large marine algae that grow on the coastal waters
of many countries.
2. Many kinds of seaweed are edible and rich in _______________ and
3. Seaweed derivatives include: _____________________,
___________________, _____________________.
4. The three main groups of seaweed are ______________________, red, and
green algae. Each provides important ingredients for manufacturing foods.
5. Alginates come from ______________________. They make water-based
products thicker, creamier, and more stable over extreme differences in
temperature, pH, and time.
6. Some products containing alginates include brownie mix, relishes,
_____________________, sauces and gravies.
7. _____________________ is extracted from certain types of red algae. It is used
in stabilizing and gelling foods, cosmetics, pharmaceuticals, and industrial
8. Some products containing carrageenan are _________________, coffee
creamer, yogurt, ___________________, pudding, toothpaste, and sour cream.
9. Beta carotene is a natural ______________________ derived from green algae.
It is used as a yellow-orange food coloring and may help prevent certain types of
10. Some products made with beta carotene are ________________________, egg
substitute, ice cream, margarine, mayonnaise, and whipped topping.
Station 3: Seaweed Article
Read the article on seaweeds and answer the following questions.
1. Why are seaweeds considered protists and not plants?
2. How do seaweeds produce food?
3. What are the four basic structures of seaweed? What are their functions?
4. What ecological role do seaweeds play in marine communities?
Station 4: Algae Video Segment
Watch the video segment about algae and answer the following questions.
1. How are algae similar to plants?
2. What colonial protist is considered an ancestor of multicellular plants?
3. Why is an eyespot important to euglenas?
4. What plant-like protists are commonly called “jewels of the sea?”
Station 5: Algae Advertisement
1. On the back of this page, create an advertisement convincing people to eat
seaweed. Your advertisement must be a combination of pictures and words.
2. Use the entire page. Be sure to be neat and informative. Use colored pencils for
your drawings.