All of the following defend the eyes EXCEPT:
a. tears.
b. lysozyme.
c. several corneal epithelial layers.
d. a hard external layer encasing the entire eyeball, including the cornea.
e. lactoferrin.

Question

All of the following defend the eyes EXCEPT:

a. tears.

b. lysozyme.

c. several corneal epithelial layers.

d. a hard external layer encasing the entire eyeball, including the cornea.

e. lactoferrin.

Accepted Answer

Welcome back, everyone. Let's look at the next question, which defense mechanism specifically targets microbes by binding up essential nutrients. A Chonju TIVA B cornea C, lachrymal gland or D lactoferrin. When we think of binding up essential nutrients in a way that prevents microbial growth. What we usually think of right away is iron, iron is necessary for microbial growth. It's a necessary nutrient. So by lowering the amount of free iron in circulation, binding up the iron in the body, you discourage microbial growth. And if we're thinking about iron, then we have a help in the name of the protein we're looking for. Just choice. D Lactoferrin can recognize that that fin has to do with iron. So, lactoferrin is an iron binding protein that's found in tears, saliva milk. That's where the lacto comes from and other bodily fluids and indeed just binds up this iron, making less of it available to encourage microbial growth. So we have our correct answer. Let's to be thorough. Let's look at the other answer choices. Um Tracy lacrimal gland might give us a little bit of pause because the lachrymal gland of course produces tears and tears do contain lactoferrin. But with this says, the defense mechanism. So the entire mechanism is lactoferrin in all the various places, not just um in the tears. So the lacrimal gland produces tears that lubricate the eye and also help protect it. And part of that protection is the lactoferrin present in it. But this doesn't describe the whole defense mechanism. So choice D is the better answer than choice C and an A and B are just parts of the eye. They do help defend the eye. But again, aren't this, they, they aren't involved in binding up essential nutrients. The choice A con conject is the thin transparent lining that uh it goes over the eye and then also lines the inside of the eyelid. This provides a physical barrier against um pathogens that might come in. Also, it contains immune cells that help protect the eye but it's not binding of essential nutrients to not our answer. Choice. And the choice B the cornea um this is that clear dome shaped structure over the front of the eye. Um Its main role is in focusing light onto the retina, but it also provides a physical barrier and also contains immune cells. So again, doesn't bind up essential nutrients and therefore not our answer. So the defense mechanism that specifically targets microbes by binding e essential nutrients is choice D lactoferrin. See you in the next video.

All of the following defend the eyes EXCEPT:
a. tears.
b. lysozyme.
c. several corneal epithelial layers.
d. a hard external layer encasing the entire eyeball, including the cornea.
e. lactoferrin.

Verified Solution

Key Concepts

Tears

Lysozyme

Corneal Structure

All of the following defend the eyes EXCEPT:a. tears.b. lysozyme.c. several corneal epithelial layers.d. a hard external layer encasing the entire eyeball, including the cornea.e. lactoferrin.

Verified Solution

Key Concepts

Tears

Lysozyme

Corneal Structure

All of the following defend the eyes EXCEPT:
a. tears.
b. lysozyme.
c. several corneal epithelial layers.
d. a hard external layer encasing the entire eyeball, including the cornea.
e. lactoferrin.