1. Protists are difficult to classify into a single system because they exhibit characteristics of both plants and animals and have diverse forms, functions, and habitats. 2. Most marine protozoans do not have contractile vacuoles because they live in salt water, which is isotonic with their cells, so they do not need to regulate osmotic pressure. 3. Common characteristics of protozoans include being eukaryotic, unicellular, and able to move using pseudopods or flagella.

1. GROUP ACTIVITY4.1
Explainthe followingquestionscomprehensively.
1. Why isit difficulttodevelopasystemof classificationforprotists?
2. Most marine protozoansdon’thave contractile vacuoles.Canyougive ahypothesissupporting
thisstatement?
3. What characteristicsare commonfor protozoans?
4. How can parasiticsporozoansmove fromone place toanotherif theydon’thave structuresfor
movement?
5. How are fungus-likeprotistsstructurallyandfunctionallyalike?
6. How isit possible forthe redalgae togrow at oceandepthsof more than 250 meters?
7. Why have the watermoldssometimesbeenplacedinthe kingdomFungi?
8. Many people sufferfromAfricansleepingsickness,butnotall of themdie fromthe disease.
Explainwhatwouldhappentoparasiticspecies,suchasthe trypanosomesif theykilledevery
memberof the hostspeciesinwhichtheylive in.
9. Foraminiferasecretehardshellsof calciumcarbonate orlimestone.Amoebas,inthe otherhand
have no protective coveringoutsidethe cell membrane.Whatare the advantagesof eachcell
structure for the survival of the organism?Whatare the disadvantages?
10. Describe the negative andpositive waysinwhichprotistsaffecthumans.
DIRECTION:Compare the differentgroupsof plantlikeprotists bycompletingthe neededinformationon
the table.(50pts)
PLANT-LIKE PROTISTS
PHYLUM COMMON
NAME
PIGMENTS FEATURES TYPE OF CELL FOOD
STORAGE
EXAMPLES