Answer:
valence electrons an element has in its outer shell, the easier it is to complete.
The most electron shells an element has, the easier it is to fill its outermost shell.
Explanation:
Non metals atoms bond to other elements by sharing or completing the valance electrons in other element. This is easily made when the other element lacks a small number of electrons, for example with Hydrogen it has 1 valance electron because of that it is easier to bond with other elements.
Receptors detect changes in the environment. For a stimulus to elicit a response, certain cells must have an appropriate receptor. Stimulation of the receptor initiates a specific signal pathway.
Answer:
D. Tricuspid → right ventricle → pulmonary valve → pulmonary circulation
Explanation:
The circulatory system is the system of organs and blood vessels which is associated with the circulation of the blood in the body.
The circulatory system is divided into two portions: the systemic circulatory system (body) and the pulmonary circulatory system (lungs).
The vena cava brings the oxygen-poor blood from the body to the right atrium from where the blood is transferred to the same side of the ventricle controlled by the tricuspid valve (atrioventricular valve).
From the right ventricle, the blood is pumped to the pulmonary artery which transports the blood to the lungs where the oxygen will be exchanged.
Thus, Option-D is correct.
Exchange of gases in fish is very efficient because of: the large surface area of the gills. the large surface area of the blood capillaries in each gill filament. the short distance required for diffusion – the outer layer of the gill filaments and the capillary walls are just one cell thick.