A Problem with Single-Group Designs Is That

question 34

Multiple Choice

A problem with single-group designs is that

• A)they are open to many confounds.
• B)there is no comparison group.
• C)there is no equivalent control group.
• D)all of the above

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Definitions:

Notochord

A flexible rod made out of a material similar to cartilage that provides support in the embryonic stages of all chordates, including humans.

Vertebral Column

Portion of the vertebrate endoskeleton that houses the spinal cord; consists of many vertebrae separated by intervertebral discs.

Dorsal Notochord

A flexible rod-shaped structure in the embryo of all chordates, including humans, that provides skeletal support and defines the primitive axis of the embryo.

Pharyngeal Pouches

Embryonic features that form structures of the face and neck in vertebrates.