Sweat glands, which secrete sweat through the skin. There are two types of sweat glands: Eccrine glands, which are all over the body and open to the pores, and Apocrine glands, which open into the hair follicles. Sebaceous glands, which secrete sebum (oil) that lubricates and waterproofs the skin. Sebaceous glands are simple and branched alveolar glands covering the body, except on the palms and soles. A sebaceous gland or oil gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals.  In humans, sebaceous glands occur in the greatest number on the face and scalp, but also on all parts of the skin except the palms of the hands and soles of the feet. In the eyelids, meibomian glands, also called tarsal glands, are a type of sebaceous gland that secrete a special type of sebum into tears. Surrounding the female nipple, areolar glands are specialized sebaceous glands for lubricating the nipple.  visible, sebaceous glands found usually on the lips, gums and inner cheeks, and genitals. Sebaceous glands are first visible from the 13th to the 16th week of fetal development, as bulging of hair follicles. The sebaceous glands of a human fetus secrete a substance called vernix caseosa, a waxy, translucent white substance coating the skin of newborns. After birth, activity of the glands decreases until there is almost no activity during ages two–six years. Then increases to a peak of activity during puberty, due to heightened levels of androgens Sebum Production: Sebaceous glands produce and secrete sebum, an oily substance. Sebum is composed of various fat molecules, including cholesterol, fatty acids, glycerides, squalene, and wax. These lipids help protect the skin and prevent dryness. Skin Moisturization: Sebum acts as a natural lubricant, shielding the skin from: Friction: It prevents damage caused by things rubbing against the skin. Moisture Loss: Sebum helps retain moisture, preventing brittle hair and dry skin. Infections: By creating a barrier, it guards against bacterial or fungal infections. Body Odor: Sebum also contributes to our body odor. Hair Health: Sebaceous glands play a role in maintaining healthy hair by preventing hair loss and dryness. Sebaceous Hyperplasia: It often affects newborns and middle-aged to elderly adults Sebaceous Cysts (Epidermoid Cysts): These are benign growths filled with sebum. Acne: Acne occurs when sebaceous glands become clogged, leading to pimples, blackheads, and whiteheads.  Sebaceous Gland Carcinoma: Hyperhidrosis: Apocrine Bromhidrosis: A primary disorder characterized by foul-smelling sweat due to bacterial breakdown of apocrine secretions. Apocrine Chromhidrosis: Another primary disorder where the apocrine secretions are colored, resulting in colored sweat. Fox–Fordyce Disease: A secondary disorder affecting apocrine glands. Hidradenitis Suppurativa.

1. GLANDS IN THE SKIN
MRS.WINCYTHIRUMURUGAN.
PROFESSOR

2. THE SKIN CONTAINS TWO MAIN TYPES OF
GLANDS
 Sweat glands, which secrete sweat through the skin.
There are two types of sweat glands:
 Eccrine glands, which are all over the body and open to the pores, and
Apocrine glands, which open into the hair follicles.
 Sebaceous glands, which secrete sebum (oil) that lubricates and waterproofs
the skin.
 Sebaceous glands are simple and branched alveolar glands covering the
body, except on the palms and soles.

3. SEBACEOUS GLAND OR OIL GLAND
 A sebaceous gland or oil gland is a microscopic exocrine gland in the skin that opens into a hair
follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin
of mammals.
 In humans, sebaceous glands occur in the greatest number on the face and scalp, but also on all
parts of the skin except the palms of the hands and soles of the feet.
 In the eyelids, meibomian glands, also called tarsal glands, are a type of sebaceous gland that
secrete a special type of sebum into tears.
 Surrounding the female nipple, areolar glands are specialized sebaceous glands for lubricating
the nipple.
 visible, sebaceous glands found usually on the lips, gums and inner cheeks, and genitals.

4. Sebaceous glands are first visible from the 13th to the 16th week of fetal
development, as bulging of hair follicles.
The sebaceous glands of a human fetus secrete a substance called vernix
caseosa, a waxy, translucent white substance coating the skin of newborns.
After birth, activity of the glands decreases until there is almost no activity during
ages two–six years.
Then increases to a peak of activity during puberty, due to heightened levels
of androgens
DEVELOPMENT OF THE SEBACEOUS
GLAND

7. 1.Sebum Production: Sebaceous glands produce and secrete sebum, an oily substance.
Sebum is composed of various fat molecules, including cholesterol, fatty acids, glycerides,
squalene, and wax. These lipids help protect the skin and prevent dryness.
2.Skin Moisturization: Sebum acts as a natural lubricant, shielding the skin from:
1. Friction: It prevents damage caused by things rubbing against the skin.
2. Moisture Loss: Sebum helps retain moisture, preventing brittle hair and dry skin.
3. Infections: By creating a barrier, it guards against bacterial or fungal infections.
3.Body Odor: Sebum also contributes to our body odor.
4.Hair Health: Sebaceous glands play a role in maintaining healthy hair by preventing hair
loss and dryness.
FUNCTIONS OF THE SEBACEOUS GLAND

9. 1.Sebaceous Hyperplasia: In this condition, sebaceous glands enlarge and produce yellow,
shiny bumps (papules) that resemble cauliflower. It often affects newborns and middle-aged to
elderly adults
2.Sebaceous Cysts (Epidermoid Cysts): These are benign growths filled with sebum. They
appear as small, painless lumps under the skin.
3.Acne: Acne occurs when sebaceous glands become clogged, leading to pimples, blackheads,
and whiteheads. Hormonal changes, bacteria, and inflammation contribute to acne development
4.Sebaceous Gland Carcinoma: This is a rare but aggressive form of cancer arising from
sebaceous glands. It typically appears as a painful, slow-growing lump on the eyelids or other
ABNORMALITIES RELATED TO SEBACEOUS GLANDS:

10. •Distribution: Eccrine sweat glands are found all over the body, including the
forehead, neck, and back areas.
•Secretions: These glands produce a watery sweat that helps cool down the body
through evaporation.
•Connection to Hair Follicles: Unlike apocrine glands, eccrine sweat glands do
not secrete into hair follicles.
•Role: They play a key role in thermoregulation by dissipating (lost) heat from the
body.
•Emotional Stress: When emotionally stressed, eccrine glands contribute to the
moisture produced in the palms and soles.
ECCRINE GLANDS:

11. 1.Hyperhidrosis: This condition involves excessive sweating. It can be focal (affecting specific
areas) or diffuse (widespread). Common areas include the palms, soles, and axillae
(armpits). While some sweating is normal, hyperhidrosis goes beyond the usual response to stress
or exercise.
2.Hypohidrosis: In contrast, hypohidrosis refers to reduced sweating. It can occur locally or more
broadly. When eccrine glands don’t function properly, the body’s cooling mechanism is
compromised.
3.Miliaria: Also known as heat rash, miliaria occurs due to obstruction of eccrine ducts. The
trapped sweat leads to small, itchy bumps on the skin.
ABNORMALITIES RELATED TO ECCRINE GLANDS:

12. 1.Distribution: Apocrine sweat glands occur in specific areas such as
the armpits, scrotum, anus, and labia majora.
2.Secretions: The secretions of apocrine glands are viscid (thicker and milky).
They contain proteins and fatty acids.
3.Connection to Hair Follicles: Apocrine glands open into hair follicles.
4.Body Odor: These glands are responsible for body odor. Bacterial
degradation of their secretions produces the distinct smell.
5.Puberty Activation: Apocrine sweat glands become active during puberty
APOCRINE GLANDS:

13. •Apocrine Bromhidrosis: A primary disorder characterized by foul-smelling
sweat due to bacterial breakdown of apocrine secretions.
•Apocrine Chromhidrosis: Another primary disorder where the apocrine
secretions are colored, resulting in colored sweat.
•Fox–Fordyce Disease: A secondary disorder affecting apocrine glands.
•Hidradenitis Suppurativa (Acne Inversa): A condition in which apocrine glands
in areas like the underarms, groin, buttocks, and under the
breasts become infected and inflamed
ABNORMALITIES RELATED TO APOCRINE GLANDS: