Here are the answers to your Cow Eye Dissection Lab Sheet.
1. Describe two observations you made when you examined the surface of the eye:
*(Note: These can vary based on what you saw, but here are the standard answers)*
a. The outer layer (sclera) is tough, white, and leathery.
b. There is a clear window in the front called the cornea that covers the colored part (iris).
2. Name the three layers you sliced through when you cut the eye:
a.
Sclera (The tough outer white layer)
b.
Choroid (The middle dark/pigmented layer)
c.
Retina (The inner nervous tissue layer)
Label the Parts of the Eye & Answer the Following Questions
*Based on the diagrams provided:*
*
Front View: a. Cornea, b. Iris, c. Pupil, d. Lens
*
Side/Back View: e. Sclera, f. Choroid, g. Retina, h. Optic Nerve, i. Tapetum Lucidum, j. Ciliary Body/Muscles, k. Vitreous Humor area
3. What is two ways that the sheep eye differs from the human eye?
1. Sheep eyes have a
Tapetum Lucidum (the shiny blue/green reflective layer behind the retina), which humans do not have.
2. Sheep pupils are often oval or rectangular shaped, whereas human pupils are round.
4. When you look through the lens of the eye on the paper, how does the image of the writing appear? Why?
The image appears
upside down and smaller. This happens because the lens is convex (curved outward), which bends (refracts) the light rays inward to focus them, flipping the image in the process.
5. Why does the eye have a "blind spot"?
The blind spot exists because that is the specific point where the
optic nerve connects to the back of the eye (retina). There are no light-sensitive cells (rods or cones) in this spot, so it cannot detect images.
6. What part is responsible for "fixing up" and upside-down image?
The
Brain (specifically the visual cortex). The eye projects the image upside down, but the brain processes the signals and flips them right-side up so we see the world correctly.
Match the following parts of the eye to their function:
7.
Retina - Contains the photoreceptors for vision.
8.
Iris - The colored portion of the eye.
9.
Lens - This structure changes shape to focus light on the retina.
10.
Pupil - The opening in the iris through which light passes.
11.
Tapetum Lucidum - Iridescent portion of the choroid layer found in nocturnal animals.
12.
Ciliary Body - Consists of muscles, which control and shape the lens.
13.
Sclera - The white of the eye.
Use the pictures to name the parts of the eye:
*(Matching the numbers on the bottom photos to standard anatomy)*
1.
Cornea (The clear dome on the front)
2.
Sclera (The white outer shell)
3.
Optic Nerve (The stem at the back)
4.
Iris (The colored ring inside)
5.
Lens (The clear disc behind the pupil)
6.
Ciliary Body / Muscles (Holding the lens)
7.
Vitreous Humor (The jelly filling the eye)
8.
Retina (The thin lining inside)
9.
Tapetum Lucidum (The shiny blue/green reflective layer)
10.
Choroid (The dark pigment layer under the retina)
11.
Pupil (The hole in the center)
12.
Suspensory Ligaments (Strands holding the lens)
Parent Tip: Review the logic above to help your child master the concept of cow eye dissection worksheet answer key.
