Use the Following Information to Answer the Question

question 59

Multiple Choice

Use the following information to answer the question.
Healthy individuals of Paramecium bursaria contain photosynthetic algal endosymbionts of the genus Chlorella. When within their hosts, the algae are referred to as zoochlorellae. In aquaria with light coming from only one side, P. bursaria gather at the well-lit side, whereas other species of Paramecium gather at the opposite side. The zoochlorellae provide their hosts with glucose and oxygen, and P. bursaria provides its zoochlorellae with protection and motility. P. bursaria can lose its zoochlorellae in two ways:
(1) if kept in darkness, the algae will die; and (2) if prey items (mostly bacteria) are absent from its habitat, P. bursaria will digest its zoochlorellae.
The motility that permits P. bursaria to move toward a light source is provided by ________.

• A) pseudopods
• B) a single flagellum featuring the 9 + 2 pattern
• C) many cilia
• D) contractile vacuoles

---

Definitions:

Alpha Rhythm

Alpha rhythm refers to the normal brainwave pattern detected by an electroencephalogram (EEG) in relaxed, wakeful states, typically with a frequency of 8-12 Hz.

Desynchronization

The loss of coordination between systems, processes, or activities that are supposed to occur simultaneously or in a synchronized manner.

Eyes Opening

A developmental milestone in young mammals, including humans, referring to the point in time when the eyelids open for the first time and the animal can see.

Periodic Waveforms

Periodic waveforms are signals that repeat their shape and amplitude over regular intervals of time, typical in many types of oscillatory systems such as electronic circuits and sound waves.