The Following Questions Refer to the Description and Table 28

question 18

Multiple Choice

The following questions refer to the description and Table 28.1 below.
Diatoms are encased in Petri-plate-like cases (valves) made of translucent hydrated silica whose thickness can be varied. The material used to store excess calories can also be varied. At certain times, diatoms store excess calories in the form of the liquid polysaccharide, laminarin, and at other times, as oil. Below are data concerning the density (specific gravity) of various components of diatoms, and of their environment.
Table 28.1: Specific Gravities of Materials Relevant to Diatoms
$$\begin{array} { l l } \text { Material } & \text { Specific Gravity } ( \mathrm { kg } / / \mathrm { m }^{3} ) \\\text { Pure water } & 1000 \\\text { Seawater } & 1026 \\\text { Hydrated silica } & 2250 \\\text { Liquid laminarin } & 1500 \\\text { Diatom oil } & 910\end{array}$$
-Which of the following statements concerning protists is False?

• A)All protists are eukaryotic organisms; many are unicellular or colonial.
• B)The primary organism that transmits malaria to humans by its bite is the tsetse fly.
• C)All apicomplexans are parasitic.
• D)Cellular slime molds have an amoeboid stage that may be followed by a stage during which spores are produced.
• E)Euglenozoans that are mixotrophic contain chloroplasts.

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Definitions:

Chronic Infections

Long-lasting infections that can persist for months or years, often causing persistent symptoms.

Short Duration

Refers to a time span that is relatively brief, often used in the context of activities or events that last for a limited period.

Stages

Progressive phases or steps within a process of development or a series of events.

Infectious Disease

A disorder caused by organisms such as bacteria, viruses, fungi, or parasites that can spread, directly or indirectly, from one person to another.