Answer: A) Two atoms share electrons so they can fill their outer shells
Explanation: A covalent bond is a type of bond formed by sharing equal number of electrons between two non-metal atoms so that both of them can attain a stable octet or duplet structure of noble gases.
In covalent bonding, there is no loss or gain of electrons between atoms. For example, the formation of chlorine molecule, chlorine atom has seven electrons in its outermost shell, remaining one electron to attain an octet structure of noble gases. Two chlorine atoms share one pair of electron, each chlorine atom donating one electron to form a pair so that each atom in the chlorine molecule attains an octet structure..
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When you are exposed to bright light, cells in the retina detect the stimulus and send it to the brain for processing. The brain commands the iris to constrict and decrease pupil size.
The structure that serves as a receptor in this system is Retina
<h3>How can we see the object?</h3>
Organisms adapted and evolved the eyes to see the surrounding environment. This ability to see begins when the visible wavelength of light enters the eye through a transparent covering called Cornea. The light enters the cornea and enters the inner of the eye through a round hole known as the pupil.
The light rays then enter the convex-shaped lens in the eye which focuses the beam of light on the back of the eye in the region of the tissue called the retina. The retina contains the photoreceptor cells-rods and cones in which the cone cells have the ability to detect three wavelengths of light especially blue, green and red which help us see various versions of the colour.
These cells convert light energy to chemical energy in the form of the action potential which gets transmitted to the part of the brain associated with the vision. This completes the pathway of the vision.
Thus, Retina is the answer.
To learn more about Retina click here:
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