0
Add your answer:
Earn +20 pts
Do sharks have notochords?
Sharks don't have notochords because they are vertebrates. All vertebrates go through an embryonic stage where a notochord is present, but then during development in the womb, this structure is replaced with a spine. The remnants of a notochord in these species can be found as the nucleus pulposus, a jelly-like center of intervertebral discs.
As the embryo develops only jawless fish retain the notochord What does this indicate about the evolution of vertebrates?
The fact that jawless fish retain the notochord during development suggests that jawed vertebrates have evolved to develop without the notochord. This indicates that the notochord is an ancestral characteristic that has been lost or modified in the evolutionary lineage leading to jawed vertebrates.
What is a stiff rod of tissue that gives rise to the spine?
The notochord is a stiff rod of tissue found in developing embryos that serves as a precursor to the spine in vertebrates. It provides structural support and plays a role in organizing the developing body plan. Over time, the notochord is replaced by the vertebral column during embryonic development.
What Animal that has notochord a nerve cord and pharyngeal pouches at some time during its development?
An example of an animal that has a notochord, nerve cord, and pharyngeal pouches at some point during its development is a chordate, such as a human. In embryonic development, humans possess these structures, which are characteristics of chordates.
At some point in their lives all chordates have what characteristics?
All chordates have a notochord, a dorsal nerve cord, pharyngeal slits, and a post-anal tail at some point in their lives. These characteristics are present during the embryonic stage, but may be lost or modified as the organism develops further.
What is similarities in embryology?
During embryonic development, all vertebrates go through similar stages such as gastrulation where three germ layers are formed, and neurulation where the nervous system begins to develop. Additionally, all vertebrates exhibit similar embryonic structures such as the notochord and pharyngeal arches. The similarities in embryology across different species provide evidence for common ancestry and evolutionary relationships.
Do tunicates and lanceletes have back bones?
No, tunicates and lancelets do not have backbones. They are invertebrates, meaning they do not possess a true backbone or vertebral column. Instead, they are part of the phylum Chordata, which includes vertebrates but also some simpler, spineless animals.
What happens to the notochord as a bat develops?
During the development of most vertebrates, the notochord becomes the nucleus pulpous. In some species, such as the sturgeon and hagfish, the notochord remains even after adulthood is reached.
What is the main function of a notochord?
The main function of a notochord is to provide structural support and flexibility to the body of an organism, particularly during development in vertebrates. It also serves as a basis for the development of the spinal column in vertebrates.
How can a notochord differ from a proper backbone?
A notochord is a flexible rod-like structure found in some chordates, providing support, while a proper backbone is a more complex structure made of vertebrae. Backbones have more specialized functions, such as protecting the spinal cord and allowing for more precise movement. Notochords are often found in embryonic stages and may be replaced by a backbone during development.
Are humans chordates?
Yes, humans are chordates. Chordates are organisms that belong to the phylum Chordata, which includes animals possessing a notochord at some stage of their development. In humans, the notochord is present during embryonic development and eventually develops into the spinal cord.
The firm flexible rod found in the dorsal area in chordates?
The firm flexible rod found in the dorsal area of chordates is called the notochord. It provides support and structure to the body, and is present during early development in all chordates. In most vertebrates, including humans, the notochord is eventually replaced by the vertebral column.
