So let's talk about glands that are specific to the integumentary system or
to the skin.
We will go into way more detail considering glands in the endocrine
portion of the MOOC.
But I wanna introduce some that are specific to this area.
And just a quick overview.
What is a gland?
Well a gland are going to be collection of epithelial cells or
epithelial tissue that are going to secrete something.
All right?
So there's two main types, there's endocrine.
And as its name would suggest it's going to release the secretion into the bloodstream.
Or just the interstitial fluid within the body.
So staying within the body.
Exocrine is going to be released onto a surface.
In our case, obviously the surface is gonna be the skin, or
out to the external environment.
You can also have the oral cavity.
So the mucus membrane associated with the oral cavity
when you talk about salivary glands in subsequent lectures.
So we're going to be focusing, obviously in this specific section on exocrine
glands.
So there's two main categories of glands associated with the integumentary system.
And we're going to start with sebaceous glands and
a lot of times we just refer to these as oil glands.
Because that's what it's releasing it's releasing what's referred to as sebum.
Or secreting sebum which is basically an oily secretion.
And as you can see here, we're looking at the specific picture,
you have a sebaceous gland.
And importantly, it is associated with the hair follicle.
So almost always, you're gonna have the sebaceous gland associated
with the hair follicle, so it will release or secrete its secretion.
And be able to kinda lubricate the hair.
That's also going to be on the external surface, or the shaft of the hair which is on the external
surface of the skin.
Now, sebaceous glands typically in younger individuals are fairly inactive.
Once an individual reaches adolescence or puberty,
then they become larger they secrete more.
You can have infections sometimes in the little region where it does secrete,
that can lead to acne.
So that's what's associated with the sebaceous glands.
All right, so the other main category of the exocrine glands associated
with the integumentary system are sudoriferous.
What we typically refer to as sweat glands.
And you have so many sweat glands associated with your skin.
And when we think of sweat glands, typically we're thinking of eccrine.
These are by far the most numerous.
And these are really important in terms of thermoregulation.
So when we think of sweat, we think about water-like odorless
sweat that we secrete throughout the body.
These are these eccrine glands.
Eccrine is actually a misnomer, that's not actually how it's released, but
we're not gonna go into those details.
But this is what you'll see in most textbooks.
The other type of sweat gland is an apocine.
These are far less numerous.
They're in specific areas of the body.
So you're gonna have them associated with the armpit or the axillary region.
Beard region, as well as in terms of external genitalia.
And you will have these sweat glands be activated in times of sexual excitement,
embarrassment.
And these are going to have an odor associated with them, so considerably less
numerous than your eccrine glands.
And they have fairly different functions as opposed to one another.
So, these are the main ideas I want you to understand in terms of the glands.
We'll come back to these in later discussions of the endocrine system.