Intro to Cosmetology

Question 1

What is cosmetology?

Answer 1

Cosmetology is the study of cosmetics and their use.

Cosmetology isthe art and science of beautifying the skin, hair and nails.

Cosmetology is the professional skill or practice of beautifyingthe face, hair, and skin.

Question 2

What is a cosmetic product?

Answer 2

A cosmetic product is any substance or mixture intended to be placed in contact with the various external parts of the human body or the teeth and the mucous membranes of the oral cavity, mainly with the aim of cleaning them, perfuming them, changing their appearance, correcting body odours, protecting them or keeping them in good condition.

Question 3

Mention 5 uses of cosmetic products.

Answer 3

i. They are used as a cleansing, moisturizing and beautifying agents.
ii. They help in enhancing attractiveness of the body.
iii. They help in altering the appearance of the body without affecting its functions.
iv. Sunscreen products help in protecting the body from UV rays and treating sunburns.
v. Acne, wrinkles, dark circles under eyes and other skin imperfections are treated or repaired by treatment products.
vi. Cosmetics help in treating skin infection.

Question 4

What is the importance of the skin?

Answer 4

The skin is the largest organ of the body, accounting for about 15% of the total adult body weight. It performs many vital functions. The skin is continuous and covers the body’s entire external surface.

Question 5

What are the three main layers of the skin?

Answer 5

i. Epidermis
ii. Dermis
iii. Hypodermis

Question 6

Discuss the 5 strata of the epidermis.

Answer 6

1. Stratum Corneum: Made up of 25-30 layers of dead keratinized cells. It is a protective waterproof layer.
2. Stratum Lucidum: Thin and translucent, it is only found in thick skin, such as the palms and soles. It consists of eleidin, a product of keratohyalin.
3. Stratum Granulosum: Grainy layer of the epidermis. It contains keratohyalin, which forms dense cytoplasmic granules that promote dehydration of the cells, as well as aggregation of keratin fibers .
4. Stratum Spinosum: Made up of several layers of flattened keratinocytes in which organelles are degenerating. These cells are attached to each other by desmosomes, giving them a spiny appearance as they shrink.
5. Stratum Basale: A single layer of low columnar cells resting on the basement membrane. They synthesize keratin. Keratinocytes give rise to most new epidermal cells that are pushed outward during cell division.
   Melanocytes lie in this layer and produce melanin.

Question 7

Discuss the dermis.

Answer 7

• The dermis is composed of fibrillar structural protein called collagen, with blood vessels, nerve endings, sweat glands, hair follicles, and nail roots.
• The papillary layer of the dermis is a zone of areolar tissue adjacent to the epidermis, projecting upward as dermal papillae.
• Blood vessels extend close to the epidermis within the papillae, and the large number of white blood cells within this layer helps prevent infection.

-The reticular layer contains dense irregular connective tissue. Stretching of the skin causes tears in this area, called linea albicantes, or stretch marks.

Question 8

Explain the hypodermis.

Answer 8

The hypodermis is composed of areolar or adipose tissue between the skin and underlying muscle. The hypodermis is 8% thicker in females.

Question 9

What is responsible for skin colour?

Answer 9

Melanin and blood vessels close to the surface.

Question 10

Mention 6 functions of the skin.

Answer 10

1. It serves as a barrier
2. Vitamin D synthesis: UV rays penetrate the skin and convert dehydrocholesterol in the blood to cholecalciferol, which is further converted to active vitamin D by the liver and kidneys
3. Cutaneous absorption
4. Sense of touch
5. Temperature regulation
6. Social interaction

Question 11

Mention 5 skin appendages

Answer 11

1. Hair
2. Nails
3. Sweat glands
4. Sebacious glands
5. Ceruminous glands
6. Breasts

Question 12

Answer True or False.

i. Almost all areas of the skin have hair, except lips, nipples, palms and soles, and portions of the fingers and genitals.
ii. The hairs that cover the fetus before birth is called lanugo
iii. Lanugo is pigmented
iv.Fine, unpigmented hair is otherwise called vellus, and covers most of the body.
v. Terminal hair is coarser, longer, and pigmented.
vi. Terminal hair can be found on the head and face (men), and in axillary and pelvic regions after puberty.

Answer 12

i. True
ii. True
iii. False
iv. True
v. True
v. True

Question 13

With the aid of a diagram, briefly discuss the anatomy of the hair.

Answer 13

• The hair itself is divided into the swollen base, where the hair originates, the root and the shaft.
• In cross section, the core of the hair (the medulla) is made up of loosely arranged cells and air spaces
• The cortex is densely packed keratinized cells
• The cuticle is a layer of overlapping scaly cells.
• The colour of hair is also due to melanin namely eumelanin and pheomelanin.

The hair follicle dips into the dermis and has two layers.
The connective tissue root sheath, derived from the dermis, surrounds the epithelial sheath, which is an extention of the epidermis.
The arrector pili muscles are small muscles attached to hair follicles in mammals, which cause the hairs to stand on end and regulate temperature.

The growth of hair is due to mitosis in cells in the stratum basale of the epidermal root sheath

Question 14

Mention 4 functions of hair.

Answer 14

1. Hair on the head controls UV exposure and heat loss.
2. Hairs at the entrance to the nose and ears and on the eyelashes offer protection
3. Eyebrows enhance facial expression
4. Hairs all over the body regulate temperature in cold conditions

Question 15

What are 2 types of sweat glands?

Answer 15

1. The eccrine sweat glands: The major sweat glands of the human body found virtually all over the skin and mainly secrete water and electrolytes through the surface of the skin e.g They areeverywhere except the lips, ear canal, prepuce, glans penis, labia minora, and clitoris.
2. Apocrine sweat glands: Secrete oily substances containing lipids, proteins and steroids through hair canals. They respond to stress and sexual stimulation. They produce a milky fluid. Apocrine sweat glands are found in the armpit, areola, perineum (between the anus and genitals), in the ear, and the eyelids.
   Rather than opening directly onto the surface of the skin, they secrete sweat into the pilary canal of the hair follicle.
   Before puberty, the apocrine sweat glands are inactive.