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.
Answer:
Explanation: mass is the correct answer
The OLFACTORY AND THE GUSTATORY SYSTEMS have receptors which die out after sometimes because of direct exposure to the environment.
The olfactory system has to do with the perception of smell while the gustatory system has to do with taste stimuli. For these two basic sense organs, their perception rate is always highest when they are newly exposed to a stimuli, after continuous exposure to the stimuli their receptors die out.
I do not know at ALL. =( Sorry.
Answer: The means for transmission of disease-causing microorganism is provided by the direct or indirect contact.
Microorganisms can cause disease only once they are transferred to the body. The disease causing microorganisms are termed as pathogens which are transmitted by several ways such as from skin to skin, by nuclei droplets, through blood and body fluids or via air. In vector transmissions the disease is carried by the parasitic insects via animals, air borne transmission occurs when microorganisms move through air or the dust particles, droplet transmission occurs by coughing, sneezing or talking by the person who is infected while indirect transmission occurs by physical contact or by touching contaminated objects.
