Starry Eyed Trivia Quiz

Answer: eyelid

The eyelids blink involuntarily when something even as small as a dust mote tries to get into the eye. The lids also blink to keep the cornea moist and healthy. The eyelashes help to catch the small particles trying to enter an eye. Both eyelids and eyelashes have a long history of cosmetic decorations.

Answer: yes

The optic disc is generally a small circular area where the nerves exit the retina and the blood vessels enter the eye. There are no rods or cones in the disc which makes for a small blind spot in each eye.

Answer: extraocular muscles

There are six muscles attached to the eyeball that control movement. This can either be voluntary like when focus is changed from something near to far, or involuntary movements such as REM sleep.

During an eye examination these muscles are often tested by requesting the patient to have their eyes follow a finger (without moving their head) as it moves left, right, up and down.

Answer: vitreous humour

Located behind the eyeball is the largest chamber of the eye, the vitreous chamber. It is filled with the vitreous humour, a liquid composed of collagen, proteins, salts and sugars. The consistency changes from the fluid-like center to the gel-like edges.

Answer: retina

The photo-receptor cells are the rods and cones that receive and respond to light. Rods help us see in dim light, and cones help us to see color. The light is then converted to nerve impulses which travel the optic nerve to the brain.

Answer: no

The lacrimal glands produce three types of tears. Basal tears are produced to lubricate and nourish the cornea. Reflex tears are in response to irritation by either small particles or very strong scents. Crying tears are generally a response to pain or strong emotions, such as happiness, sadness or anger.

Answer: cornea

The cornea is composed of several layers: epithelium, Bowman's membrane, stroma, Descemet's membrane, and the endothelium. The cornea helps to protect the eye from dirt and helps focus any light coming into the eye.

If the cornea curvature becomes irregular this can cause the vision to become blurred. This is called astigmatism and can normally be corrected by eye wear or surgery.

Answer: iris

The eye color is determined by genetics. Eyes with little pigmentation appear blue, increased pigmentation generally darkens the iris color to a dark brown. The iris can be found between the cornea and lens. There are two muscles, a sphincter muscle to reduce the size of pupil, and a dilator which expands the pupil opening.

Answer: lens

The ability of the lens to change shape allows the eye to change focus. The light is filtered through the iris and then refracted on the retina. The retina then converts the image to nerve signals that are sent to the brain.

Answer: sclera

The sclera can be seen around the iris, but it actually extends from the cornea to the optic nerve at the back of the eye. This part of your eye doesn't affect your ability to see, but it does help to protect the eyeball.