Answer:they possess notochord,dorsal tubular nerve cord , pharyngeal pouches
Explanation:chordates are animals which possess the notochord.examples are humans,birds,fishes etc
At a time in the life cycle,a chordates possesses a stiff,dorsal rod which is supporting in nature (the notochord).
They also possesses a tail that extends from behind the anus.
They possess a hollow nerve cord.
They possess gills slit.
These characteristics are present developing embryo and may disappear as the embryo matures.
In humans,the notochord is replaced by the spinal column of the vertebrate.
Answer:
This is not generally realized but is vital when designing aeration systems for growing on warm water species. Most research indicates that trout consume around 200 – 250 mg O2/kg/hour. I regularly record carp consuming three times as much at 700- 800 mg/kg/hour under optimal growing conditions.
Explanation:
I suppose it is the density, having more pockets of air in between the granules of sawdust. Air has oxygen. What does a fire need to strive? Oxygen.
It gives the plant ENOUGH oxygen to help it
