TX Bar TX Barber Scientific Concepts 3 — Questions and Answers
Question 1: In the context of electricity used in barbering, what does the term 'ampere' measure?
- The pressure or force of electrical current
- The rate of flow of electrical current (Correct answer)
- The resistance to electrical flow
- The total electrical power consumed
Correct answer: The rate of flow of electrical current
Ampere (amp) measures the rate of flow of electrical current — specifically, the number of electrons moving past a point per second.
Question 2: Infrared light used in heat lamps during barbering treatments penetrates tissue primarily to produce:
- Germicidal effects on surface bacteria
- Deep heat that increases blood circulation (Correct answer)
- Vitamin D synthesis in the skin
- Coagulation of surface proteins
Correct answer: Deep heat that increases blood circulation
Infrared rays penetrate deeply into skin tissue, producing heat that dilates blood vessels and increases circulation, aiding in relaxation and product absorption.
Question 3: The high-frequency current used in barbering produces which of the following therapeutic effects?
- Muscle contraction and toning
- Germicidal and stimulating effects on the scalp (Correct answer)
- Deep tissue coagulation for scar treatment
- Numbing of nerve endings to reduce pain
Correct answer: Germicidal and stimulating effects on the scalp
High-frequency current generates heat within tissues and produces ozone at the skin surface, which has germicidal properties and stimulates the scalp.
Question 4: Which principle explains why two like electrical poles repel each other and why galvanic current can drive solutions into the skin?
- Ohm's Law
- Iontophoresis via electrophoresis principles (Correct answer)
- The law of conservation of energy
- Faraday's electromagnetic induction
Correct answer: Iontophoresis via electrophoresis principles
Iontophoresis uses the principle that like charges repel — a negative electrode drives negative ions (anions) into the skin while a positive electrode drives positive ions (cations).
Question 5: The chemical compound melanin, which gives hair its color, is produced by cells called:
- Keratinocytes
- Melanocytes (Correct answer)
- Fibroblasts
- Sebocytes
Correct answer: Melanocytes
Melanocytes are specialized cells in the hair bulb and epidermis that produce melanin pigment, which is then transferred to cortical cells of the hair shaft.
Question 6: When an alkaline chemical relaxer is applied to hair, it breaks which chemical bonds in the cortex to straighten the hair?
- Hydrogen bonds
- Salt bonds
- Disulfide bonds (Correct answer)
- Peptide bonds
Correct answer: Disulfide bonds
Alkaline relaxers (lye and no-lye) permanently straighten hair by breaking disulfide bonds in the cortex; these bonds do not reform in the straightened position.
Question 7: The cortex of the hair shaft is primarily composed of which protein?
- Collagen
- Elastin
- Keratin (Correct answer)
- Fibrin
Correct answer: Keratin
The hair cortex is made primarily of alpha-keratin, a fibrous structural protein containing high levels of the amino acid cysteine which forms disulfide bonds.
TX Bar TX Barber Scientific Concepts 3
In the context of electricity used in barbering, what does the term 'ampere' measure?