Sponges absent
Cnidarians not jointed (Aquatic organisms, all have tentacles with nematocysts - stinging cells, used to capture food.)
Roundworms absent (AKA nematodes are unsegmented, colorless and do not have appendages).
Annelids not jointed (With the exception of leeches, all annelids have chitonous hair-like structures projecting from their cuticle. These appendages fulfill different functions in different species.)
Mollusks not jointed (Invertebrates that lack hard appendages such as legs or antennae)
Arthropods jointed (the arthropods are the only invertebrates to have jointed appendages)
Echinoderms not jointed (Due to their radial symmetry, all echinoderms have appendages which point outward from the center of the body like the spokes on a wheel.)
and vertebrate jointed
The correct answer of the given question above would be option D. The option that did not occur during the Cenozoic era is the formation of the ozone layer. The ozone layer has long been there before any era since it is part of the earth's atmosphere. Hope this answer helps.
<h3><u>Answer;</u></h3>
<em>The marrow in the bones of the skeletal system helps produce the cells in the blood, which is the key fluid of circulatory system</em>
<h3><u>Explanation;</u></h3>
- <em><u>Skeletal system is a system in the body that is made up of cartilage and calcified bone that work together by helping in the smooth movement process of the body. </u></em>
- <em><u>Circulatory system on the other hand is a system of the body that is made up of blood vessels that carry blood away and towards the heart. The system helps in transport of oxygen and nutrients in all the body tissues, and also transport of carbon dioxide and wastes out of the tissues.</u></em>
- <em><u>The calcified bones of the skeletal system work with the circulatory system, such that the bone marrow in these bones helps in the production of blood cells such as red blood cells and white blood cells.</u></em>
Answer:
the first,second, and third are the answer if this is multichoice which i am guessing it is.
Explanation:
