Answer:
gills
Explanation: A fish without a jaw was the first vertebrate to evolve. These fish used filtration to capture their food and sucked water and debris from the sea through their mouths and then released the water and trash through their gills. Some features are as follows:
1. They have a notocorda that serves as support through the back of the fish.
2. Gill bags. These organs are responsible for filtering the oxygen in the water.
3. A pineal eye that is sensitive to light
4. A cartilaginous skeleton
Answer:
increasing pressure inside the lymph capillary
Explanation:
Lymph is a fluid like the blood which carry the White blood cells which can fight against the infection. The lymph flows in separate vessels called lymphatic vessels.
The lymphatic vessel is very thin-walled smooth muscle containing tube-like structure which allows the transport of lymph.
The lymph vessel like blood vessel contains the valves called mini valves which prevent the backward flow of the lymph.
When the pressure in the tiny lymph capillaries which supplies lymph to the organs increases, the mini valves closes to prevent backflow of lymph and is the mechanism of lymph flow.
Thus, the selected option is the correct answer.
An advantage to reproducing sexually, is the genetic variation the offspring will obtain.
<span>In a neuron, the opening of sodium gates typically leads to open and allows the exit of sodium ions out the cell. The neuron that contains for why myelinated fibers conduct signals faster than unmyelinated fbers are the d</span>iffusion of ions along the axoplasm is faster. At the same time, a traveling wave of excitation is <span>a nerve signal.</span>
This might be a bad idea as a lot of animals live in wetlands