Cephalization describes the process by which organisms develop a distinct head. The head of a cephalized organism contains a concentrated group of nerves, or brain, that controls the rest of the organism, as well as specialized organs for consumption and perception, like mouths, eyes and ears. Cephalized organisms exhibit a distinct division between parts of the body; they have a front, back, top and bottom. These animals comprise the bulk of animals that are encountered on a daily basis.
sea star following organisms exhibits cephalization
I think Autorhythmic fibers are fibers that are self excitable or on their own for example some cardiac muscle. They repeatedly generate action potentials that trigger heart contractions.They continue to stimulate a heart to beat even when it is removed from the body. In comparison to contractile fibers, autorhythmic fibers are self excitable and do not require nervous system stimulation to trigger contractions. Contractile fibers have stable resting membrane potentials of -90mV, when a contractile fibers reaches threshold by action potential, the voltage gated fast sodium ions channels will open.
Lithified ash (or ash mixed with pyroclastic fragments) forms a volcaniclastic rock called a Tuff.
- A form of rock called tuff is created when volcanic ash is blasted from a vent during an eruption.
- The ash is transformed into a rock after ejection and deposition. Tuff is defined as rock with an ash content of more than 75%, whereas tuffaceous refers to rock with an ash content of 25% to 75%.
- The thickness of tuff often decreases with distance from the volcano and is usually greatest close to the volcanic vent. The typical shape of a tuff deposit is that of a "lens," not a "layer."
- Tuff may also be thickest on the vent's side that faces away from the wind or on the side facing the direction of the blast.
learn more about tuff here: brainly.com/question/27870503
#SPJ4
A dependent variable is how they are recording, measuring or keeping track of the science experiment their doing.
A independent variable is the things/types there using to compare what is the most/least affective in the experiment.
A controlled variable is something that stays the same in the experiment or a group/set used for comparison