Our nervous system runs on chemical synapses ! that means we need chemical to transfer information from one neuron to another !
so when the signal reaches the synaptic knob of one neuron , it stimulates the neurotransmitters containing vacuoles to release the neurotransmitters !
the neurotransmitters may be dopamine, acetylcholine etc and after reaching the dendrites of other neuron, it stimulates signal in the other neuron and thus a signal travel from one part of body to other !
The independent variable is the new plant food
The answer is D. In a
geological era, when the plants and animals
in the then environment die, they get buried
in sediments. These sediments are covered
by other sediments of another geological
time within which are the remains of dead species
of the then geological era. These sediments from different geological times have different properties hence
form visible strata that can be studied to identify the kind of environment in the then geological time. Their
fossils can also be studied to identify
the kind of species that roamed the earth during the time.
Alleles are the individual genes that give rise to certain characteristics in an organism.
When an allele is "fixed" to a population, this means that the characteristic will be constant & most likely will not change until the environment changes as well.
Like with arctic hare, the alleles that influence the color of their coats (white in the winter & brown in the spring/summer) will stay because any fur pattern other than the aforementioned characteristics with result in becoming someone else's food with the lack of camouflage.
Hope that helps!
