Which One of the Following Statements Regarding Metazoan Origins Is

question 42

Multiple Choice

Which one of the following statements regarding metazoan origins is true?

• A)Origin of the metazoa has been clearly elucidated and involves ancestry from a colonial flagellate stock.
• B)Metazoans are derived twice.One lineage involves a colonial flagellate stock,and the other lineage involves placozoan-like ancestors.
• C)Metazoans arose from a multinucleate ciliate where cell boundaries eventually formed around each nucleus.
• D)Placozoans may be similar to the single ancestral state.Features like their small nuclear genome and their large mitochondrial genome are features that may be derived from a common ancestor shared with some animal outgroups.The nuclear and mitochondrial genomes of the Placozoa suggest ancestry with animal outgroups.

---

Definitions:

Contiguity

The principle stating that events occurring close together in time or space are readily associated with each other.

Unconditioned Stimulus

In the process of classical conditioning, a stimulus instinctively and effortlessly elicits a reaction without the need for any previous learning.

Reliable Indicator

A metric or sign that consistently and accurately measures or predicts a specific outcome or condition.

Conditioned Stimulus

A previously neutral stimulus that, after becoming associated with an unconditioned stimulus, now elicits a response.