Vertebrates and tunicates share a. jaws adapted for feeding. b. a high degree of cephalization. c. an endoskeleton that includes a skull. d. a notochord and a dorsal, hollow nerve cord.

Verified step by step guidance

1. Step 1: Understand the question. The question is asking which characteristic is shared by both vertebrates and tunicates.
2. Step 2: Recall the characteristics of vertebrates and tunicates. Vertebrates are a large group of animals that have a backbone or spinal column, including mammals, birds, reptiles, amphibians, and fishes. Tunicates are marine invertebrates that often lack the common features of chordates, but during their larval stage, they possess a notochord and a dorsal, hollow nerve cord.
3. Step 3: Evaluate each option. Option a, jaws adapted for feeding, is not correct because tunicates do not have jaws. Option b, a high degree of cephalization, is not correct because tunicates do not have a high degree of cephalization. Option c, an endoskeleton that includes a skull, is not correct because tunicates do not have an endoskeleton or a skull.
4. Step 4: Choose the correct option. Option d, a notochord and a dorsal, hollow nerve cord, is correct because both vertebrates and tunicates have these features at some stage in their life cycle.
5. Step 5: Confirm the answer. Both vertebrates and tunicates share a notochord and a dorsal, hollow nerve cord.

Key Concepts

Notochord

The notochord is a flexible, rod-like structure found in the embryos of all chordates, including vertebrates and tunicates. It provides skeletal support and serves as a precursor to the vertebral column in vertebrates. The presence of a notochord is a defining characteristic of the phylum Chordata, highlighting the evolutionary relationship between these groups.

Dorsal Hollow Nerve Cord

The dorsal hollow nerve cord is another key feature of chordates, located above the notochord. It develops into the central nervous system, which includes the brain and spinal cord in vertebrates. This structure is crucial for the coordination of movement and processing of sensory information, emphasizing the shared developmental pathways of vertebrates and tunicates.

Cephalization

Cephalization refers to the evolutionary trend where sensory organs and nervous tissue become concentrated at one end of the organism, typically the head. This adaptation allows for more efficient processing of sensory information and coordination of movement. While vertebrates exhibit a high degree of cephalization, tunicates show less, indicating a divergence in evolutionary complexity despite their shared ancestry.