The correct answer for both blanks is "Sodium".
Sodium ions are necessary in small quantities for some sorts of flora, but sodium as a nutrient is extra usually wanted in large quantities by using animals, due to their use of it for era of nerve impulses and for upkeep of electrolyte balance and fluid stability. In animals, sodium ions are vital for the aforementioned capabilities and for coronary heart hobby and sure metabolic functions.
Answer:
Bones. They are vertabrates, which means they have a backbone
Explanation:
Fish, reptiles, amphibians, birds and mammals all have bones
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.
