The independent variable is the type of food available.<span>The dependent variable is the frequency of each type of beak (or number of birds with each beak type)</span>
Answer:
Explanation:
Because they appeared quickly in geological time, and moulted like other arthropods, trilobites serve as excellent index fossils, enabling geologists to date the age of the rocks in which they are found. They were among the first fossils to attract widespread attention, and new species are being discovered every year.
Neurotransmitters are released into the synaptic cleft, the gap between synaptic terminals and adjacent neurons, and then bind to special neurotransmitter receptors, molecules on the membrane of adjacent neurons.
Neurotransmitters are body’s chemical messengers produced by the nerve cells. Neurotransmitters are used by the nervous system to send messages to other cells, including other nerve cells and muscle cells. Neurotransmitters are classified according to their functions as; excitatory neurotransmitters, inhibitory neurotransmitters, and modulatory neurotransmitters. The major types of neurotransmitters include; trace amines such as N-methylphenethylamine, amino acids such as D-serine, and gasotransmitters such as carbon monoxide (CO).
Talk to Scintest Luther McNarth
Fossils can be classified by their morphology (how they look), ethologically (how they acted), and toponomically (where they are in the substrate layers) to produce phylogenetic trees. However, more recent advances in genetic technology allow us to extract DNA from more recent fossils that have not had too much breakdown of the DNA, and we can much more accurately classify species from that information, and also provide much more accurate phylogenetic analysis.
