Placing Sponges as the Basal Metazoans on the Basis of Lack

question 56

Multiple Choice

Placing sponges as the basal metazoans on the basis of lack of tissues implies which of the following?

• A) Sponge ancestors never had tissues.
• B) Modern-day sponges have lost the ability to form tissues.
• C) Multicellular, modern-day choanoflagellates can form tissues.
• D) Sponges do not have nerve cells.

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Definitions:

Nervous System

The body's complex network of cells and tissues, consisting of the central and peripheral nervous systems, responsible for coordinating voluntary and involuntary actions and transmitting signals between different parts of the body.

Hypothalamus

A small region of the brain located below the thalamus, responsible for regulating many bodily functions, including hunger, thirst, sleep, and emotional activity.

Thalamus

A structure in the brain located above the brainstem, that serves as a relay station for transmitting sensory information to the cerebral cortex.

Hormone

Chemical messengers produced by the endocrine glands that regulate various body functions and processes.