Which statement is true for cephalochordates? notochord is present only in the larval stage; it is absent in adults. notochord is present in the larval stage; it transforms to vertebrae in adults. notochord is present throughout their lives.

Which of the following statements accurately defines epidermis? a. a thick protein fiber composed of the protein collagen b. hard, dense bone tissue found on the outer surface of a bone c. single layer of epithelial cells and the underlying basal lamina d. outer, protective layer of the skin composed of stratified squamous keratinized epithelial tissue