Answer: A pictograph is a symbol for a word or phrase.
i hope this helps you :D
A variation is a reference to the differences or deviations, such as the structure and form, as for crossing over is the exchange of genetic material between the non-sister chromatids of the homologous chromosomes during meiosis.
1. electrical signals travel toward the heart. 2. signal received by the atrioventricular node. 3.signal by the nodes in the atrium. 4.the atria contracts. 5. signal transferred to the ventricles. 6. the ventricles contract.
Lack predators and other natural controls
Highly folded membranes allow for more surface area which allows more proteins to help function.
