Topical Drug Delivery

Question 1

Layers of the epidermis

Answer 1

Stratum corneum 
Stratum lucidum 
Stratum granulosum 
Stratum spinosum 
Stratum basale

Question 2

Stratum corneum

Answer 2

It is called non -viable or cornified layer
It is 10 micro meter thick
It is made up of dead,keratinized protein cells
After 2 weeks the dead cells are replaced as they worn off
It is a tough layer that is water resistant (prevent water loss)
It is selectively permeable

Question 3

Why is SC tough

Answer 3

Keratin makes the stratum corneum tough
Lipids makes it water resistant
This prevents water loss

Question 4

Dense ultra epidermal cover

Answer 4

It is a thin sheet that is formed by continuous overlap of cells covering the stratum corneum

Question 5

Importance of SC

Answer 5

It protects the underlying tissues of the skin from pathogens and a little from injury
It prevents excessive water loss

Question 6

Skin appendages

Answer 6

Hair follicles
Sebaceous glands
Eccrine glands
Appocrine glands

Question 7

Hair follicles

Answer 7

Hair are made up of keratinocytes in a form of scales and plates
They are synthesized at the base of follicle in the hair bulb

Question 8

Sebaceous glands

Answer 8

They secrete and oily substance called sebum
Sebum is responsible for plasticizing and sealing the stratum corneum
Maintains the pH at 5 which is an acidic condition

Question 9

Eccrine glands

Answer 9

The are salty glands
They are found on the entire surface of the body but mainly on the palms and soles of your feet
They secrete a dilute aqueous salty solution

Question 10

Apoccrine glands

Answer 10

They are the smelly glands
They are found on the armpits, genital and around the nipples
They secrete a milky substance with proteins,lipids,saccharides and liposaccharides
They are responsible for body odour especially if bacterial action is involved

Question 11

Function of the skin

Answer 11

Containment of body fluids and tissues 
Electrical barrier 
Radiation barrier 
Chemical barrier 
Microbial barrier

Question 12

Skin natural moisturizing factors

Answer 12

Amino acids
Hydroxy acids
Urea
Inorganic ions 
Skin lipids

Question 13

Elasticity of the skin

Answer 13

It is dependent on the balance of lipids and water conjuction with the keratin fibres

Question 14

Epidermal lipids

Answer 14

Ceramide/cetrimide
Cholesterol
3 fatty acids