is the 2 option ...n......
Answer:
Explanation:
Dispersion and vicariance are the processes by which speciation is generated in biogeography.
A phylogeny represents the evolutionary relationships between different species.
In this phylogeny, species 5, 1, 6 and 3 originated from vicariance processes, and their position in the phylogenetic tree is due to the order of separation of the mentioned regions. Species 2 and 4 originated from dispersal processes, and are expected to have a closer evolutionary relationship with the species that were in the areas from which they were dispersed, in this case, with Africa and Australia respectively.
The simultaneous arrival of graded depolarization and a graded hyperpolarization of equal but opposite magnitude at a particular location on the dendritic membrane is likely to cancel the effects of each other and no change will occur in the membrane potential.
Explanation:
Graded potentials lead to temporary minor changes in the membrane potential associated with neuron’s dendrites. The amount of change caused depends upon the size and duration of the stimulus. These can be depolarizing or hyperpolarizing.
Graded depolarization occurs due to the entry of sodium or calcium ions; whereas, graded hyperpolarization occurs due to exit of potassium ions or entry of chloride ions.
When equal but opposite magnitude of graded depolarization and hyperpolarization occurs at a particular dendride of a neuron, the positive and negative charges get neutralized causing little or no effect on the total membrane potential.
Various species of the flowering plant of the genus <em>Chrysanthemum </em>have 18, 36, 54, 72, and 90 chromosomes. The variation is likely due to polyploidy.
<h3>What is polyploidy?</h3>
Polyploidy can be defined as the number of complete sets of chromosomes in a given cell of an organism.
A diploid organism contains two complete sets of homo-logous chromosomes in its somatic cells.
Many organisms used polyploidy as an evolutionary strategy for adaptation to challenging environmental conditions.
Learn more about polyploidy here:
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