Question

classifying organisms by cell structure
a biologist is exploring three different environments: a volcanic hot spring, a deep ocean trench, and a temperate forest. in each environment, the biologist discovers new life forms. after closely examining these organisms under a microscope, the biologist observes the following:

• the organism from the hot spring appears to have cell structures that resemble those of ancient microorganisms.
• the organism from the ocean trench is unicellular and does not contain membrane - bound organelles.
• the organism from the temperate forest is multicellular and shows evidence of complex internal structures, including a nucleus.

based on these observations, the biologist classifies the organisms into three domains: archaea for the organism from the hot spring, bacteria for the organism from the ocean trench, and eukarya for the organism from the temperate forest.

1. based on the evidence, which of the following claims is not true about unicellular and multicellular organisms?

(1) unicellular organisms perform all necessary functions within one cell, while multicellular organisms have specialized cells for different functions.
(2) unicellular organisms are always prokaryotic, while multicellular organisms are always eukaryotic.
(3) multicellular organisms are typically larger and more complex than unicellular organisms.
(4) unicellular organisms often rely on structures like flagella or cilia for movement, while multicellular organisms can have more complex systems for movement.

Explanation:

Unicellular organisms are not always prokaryotic (they can be eukaryotic like some protists) and multicellular organisms are not always eukaryotic (though most are). Multicellular organisms are typically larger and more complex, and unicellular ones often use flagella or cilia for movement while multicellular ones can have more complex movement systems. Also, unicellular organisms perform all functions in one cell while multicellular have specialized cells.

Answer:

(2) Unicellular organisms are always prokaryotic, while multicellular organisms are always eukaryotic.