Answer:
The three-chambered hearts of amphibians and nonbird reptiles are facultative, allowing variation in blood flow through the heart.
Explanation:
In Anatomy, cardiac cycle can be defined as a complete heartbeat of the human heart which comprises of sequential alternating contraction and relaxation of the atria and ventricles, therefore causing blood to flow unidirectionally (one direction) throughout the human body.
Generally, the cardiac cycle occurs in two (2) stages;
I. Diastole : in this stage, the ventricles is relaxed and would be filled with blood.
II. Systole: at this stage, the muscles contracts and thus, allow blood to be pushed through the atria.
All amphibians and reptiles except for crocodiles (having four-chambered heart) have three-chambered hearts, which typically comprises of a partially divided ventricle and two atria.
Hence, the correct statement about the three-chambered hearts of amphibians and nonbird reptiles is that, the three-chambered hearts of amphibians and nonbird reptiles are facultative, allowing variation in blood flow through the heart due to the partially divided ventricle.
Calculating waist to hip ratio. This is indicative of excessive fat accumulation (of a certain type) which could be indicative of a higher risk for cardiovascular diseases
<span>The correct answer is A, B and D. Biogeochemical cycles are central to the ecology of earth system. They make the essentail elements accessible and available for the organisms, and maintain their levels, so that the ecology is ot disrupted. The elements move through abiotic and biotic factors, in these cycles, and a state of equilibrium is maintained n the ecosystem. The carbon dioxide levels are responsible fr the temperature of the earth. If Carbon cycles would not have existed, then there would have been a disruption in maintaining the global temperature. Biogeochemical cycles basically continuously recycles the essential materials, for sustaining the life-forms.</span>
A, b , and c are true. The monomer of sugar polymers is monosaccharides
Ribosomes are in charge of making proteins.
