Answer:
At the base of Actinopterygii
*This is a unique characteristic of this group.
Explanation:
A peculiar characteristic organ observed in ray-finned fish (as well as in Sarcopterygii, or lobe-finned fish) but not in cartilaginous fish like shark is the swim bladder.
This organ is often described to be a sac containing gas. It helps these set of fish adjust its buoyancy and its position in the water by regulating the concentration of gas present in it.
The swim bladder is formed as a pouch coming off the embryonic digestive tract, and in chondrosteans and holosteans, with a set of teleosts e.g. the eels, it maintains an open pathway to the esophagus. In majority of the bony fish, the swim bladder is totally sealed off, as gas levels in their swim bladder are regulated by producing gas into the bladder via a network of capillaries, the rete mirabile (Latin word for "marvelous net").
The swim bladder is homologous to the lungs of tetrapods. Since they are formed in the same vein. Few fishes that have an open swim bladder employs it as a breathing organ.
B - energy flow from one tropic level to the next
Answer:
They slowly lose energy.
Explanation:
High-energy electrons give the chain either NADH or FADH2 to complete it.
Low-energy electrons form water by decreasing the oxygen molecules.
Answer:
The fossil record supports a "biological" type of evidence.
Explanation:
<u>Fossils-</u> this refers to the <em>remains of prehistoric organism.</em><em> </em>It provides a trace of a <em><u>once-living plant, animal or organism. </u></em>
When it comes to evolution, fossils provide a biological type of evidence. This means that,<u><em> it shows how organism have greatly changed from the past.</em></u> When you study fossil records, you can compare it with the animal, plant or human structure nowadays. You can compare them side-by-side. So, you'd get that idea on how prehistoric things lived in the past and how they evolved up to the present day or became extinct.
<em>Most of the fossils can be found on sedimentary rocks.</em> You can also tell their ages according to which layer they belong. It is said that older layers consist of older fossils and they appear at the bottom while younger layers consist of younger fossils and they appear on top.
