Milady Cosmetology Chapter 2: General Anatomy and Physiology

Why Study Anatomy and Physiology?

Cosmetology services affect the skin; muscles; nerves; circulatory system; and bones of the head, face, neck, shoulders, arms, hands, lower legs, and feet.

We should have a thorough understanding of anatomy and physiology because:

Scalp manipulations, facials, manicures, and pedicures are all common cosmetology procedures that rely on understanding human anatomy.
Recognizing healthy hair, skin, and nails is an important infection control step, as is recognizing conditions that require referral to a healthcare professional. Diagnosing or treating any illness is out of a cosmetologist’s scope of practice.
Working with the bones of the face and skull contributes to flattering haircuts, hairstyles, and makeup applications

Terms

Anatomy — (aka. gross anatomy) The study of human body structures, how the body parts are organized, and the science of the interconnected structure of organisms, or their parts.

Physiology — the study of the functions or activities performed by the body structures.

Cell Structure and Functions

Bacteria, plants, animals and humans all have cells. The cell is made up of protoplasm where nutrients, mineral salts, and water are present.

Most cells also include:

The nucleus — Controls the growth and reproduction of the cell and contains the cell’s genetic material. Located in the center of the cell.
Cytoplasm — Watery fluid that surrounds the nucleus. Provides structure for the cell’s parts so they can move freely within the membrane. Enzymes in the cytoplasm help digest and real down other molecules for food.
The cell membrane — Thin layer of tissue that surrounds the cell. Protects the cell from its surroundings. Semipermeable, it allows certain substances to enter the cell.

Mitosis is the process of cell division that produces two identical daughter cells from a single parent cell. Cells require factorable conditions to grow and reproduce like food supply, oxygen, water, suitable temperatures and the ability to remove waste.

Cells convert nutrients to energy through metabolism. There are two types:

Anabolism — Combining simple molecules to form a complex molecule. Requires energy.
Catabolism — Breaking down complex molecules into simple molecules. Releases energy.

Terms

Cells — The basic units of all living things

Tissues

There are 4 types of tissues in the body:

Connective tissue — Fibrous tissue that binds and supports other body tissues and organs.
Epithelial tissue — Provides a covering that protects the body and is found within many parts of the body such as skin, mucous membranes, digestive and respiratory organs, the lining of the mouth, the lining of the heart, and the glands.
Nerve tissue — Carries messages to and from the brain and controls and coordinates all bodily functions.
Muscle tissue — contracts and moves various parts of the body.

Organs and Body Systems

Circulatory — Heart, blood vessels. Controls blood movement throughout the body. Massage affects the circulatory system and good blood flow affects hair growth. Facial services and shaving benefit from awareness of arteries and veins for safety.
Digestive — Stomach, intestines, esophagus, salivary glands. Breaks food down into nutrients or waste. Good nutrition allows optimum functioning of all body systems.
Endocrine — Endocrine glands, hormones. Controls hormone levels within the body that determine growth, development, reproduction, and health of the entire body. Hormones produced by the endocrine system directly impact hair and skin. Some skin and hair conditions are a result of hormones.
Excretory — Kidneys, liver, skin, large intestine, lungs. Eliminates waste from the body, reducing buildup of toxins. The excretory system eliminates toxic substances that can affect other body system functions.
Immune (lymphatic) — Lymph, lymph nodes, lymph vessels, spleen. Protects the body from disease by developing immunities and destroying pathogens and toxins. Massaging affects the lymphatic system.
Integumentary — Skin, oil glands, sweat gland, sweat glands, hair, nails. Provides a protective covering and regulates body temperature. Cosmetology services are directly affected by the health of the integumentary system.
Muscular — Muscles. Covers, shapes, and holds the skeletal system in place. Muscles contract to allow for movement of body structures. Massage performed during cosmetology services affect the muscular system, having an understanding of it will prevent injuries.
Nervous — Brain, spinal cord, nerves, eyes. Coordinates all other body systems allowing them to work efficiently and react to the environment. Cosmetologists need an understanding of this system to provide safe and effective facials and nail services.
Reproductive — Uterus, ovaries, penis, testes. Produces offspring and differentiates males from females at birth. The reproductive and hormonal changes that occur affect hair growth, hair loss and the skin.
Respiratory — Lungs, air passages. Makes blood and oxygen available to the body through respiration. Eliminates carbon dioxide. Infection can be spread through respiration, affecting safety and cleanliness.
Skeletal — Bones, joints. Forms the physical foundation of the body. 206 bones connected with movable and unmovable joints. It is important to know for protecting your own body mechanics when working, as well as bone structure when providing treatments, including makeup applications.

Skeletal System

This system forms the body’s physical foundation and is composed of 206 bones of different shapes and sizes. A joint connects two or more bones. There are 2 types of joints:

Movable — joints that allow movement. In elbows, knees, and hips
Immovable — Allow little to no movement (exceptions during childbirth). In the skull and pelvis.

Fun Facts:

Joint pain is usually caused by inflammation of the tissue surrounding the joint. You have more than 230 movable and semi-movable joints in the body.
Tooth enamel is the hardest bone in the body and has connective tissue with 1/3 of organic matter (cells and blood) and 2/3 minerals (calcium carbonate and calcium phosphate)

Primary functions of the skeletal system are to:

Give body shape and support
Protect internal structures and organs
Serve as attachments to muscles and levers to produce movement
Help produce red and white blood cells
Store most of the body’s calcium supply, phosphorus, magnesium, and sodium.

Skull Bones

The skull is divided into 2 parts

Cranium — Oval, bony case of 8 bones protecting the brain
Facial skeleton — The framework of the face. Has 14 bones

Cranial Bones

Parietal bones (2) — Forms the sides and top of the cranium
Temporal bones (2) — Forms the sides of the head in the ear region
Occipital bone — Below the parietal bones. Forms the back of the skull above the nape.
Frontal bone — Forms the forehead
Sphenoid bone — forms base and sides of skull
Ethmoid bone — separates nasal cavity from brain

Facial Bones

There are 14 facial bones, but only 9 are most involved in cosmetology.

Zygomatic bones (2) — Aka. cheekbones or malar bones. Form the prominence of the cheeks and outer part of the eye socket
Lacrimal bones (2) — Thin bones located in the front inside wall of the eye sockets (orbits)
Nasal bones (2) — Bones that form the bridge of the nose
Maxillae bones (2) — Bones that form the upper jaw
Mandible — largest and strongest bone of the face that forms the lower jaw

Neck Bones

Cervical vertebrae (7) — Located below the skull. Provide support, structure and flexibility of the neck.
Hyoid bone — U-shaped at the base of the tongue that supports it and its muscles. Only bone of the throat

Chest and Shoulder Bones

Scapula (2) — Aka. shoulder blade. Large, flat, triangular bone of the shoulder.
Clavicle — Aka. collarbone. Joints the sternum and scapula

Arm and Hand Bones

Carpus (8) — Aka. the wrist. Flexible joint composed of small irregular bones called carpals.
Phalanges — Aka. digits. bones of the fingers or toes. 3 in each finger and 2 in each thumb.
Metacarpus (5) — Or metacarpals. In the palm between the carus and phalanges.
Radius — Smaller bone in the forearm on the same side as the thumb.
Ulna — Inner and larger bone in the forearm on the side of the pinky finger.
Humerus — Uppermost and largest bone in the arm. Extends from the elbow to the shoulder.

Leg, Ankle and Foot Bones

Patella — Aka. kneecap. Forms kneecap joint.
Tibia — Aka. the shinbone. Larger of the 2 leg bones. Below the knee on the big toe side that supports most of the body’s weight.
Fibula — On the little-toe side of the lower leg. smaller of the 2 leg bones below the knee.
Tarsals (7) — Irregularly shaped bones in the ankle area including the talus, calcaneus (heel), navicular, cuboid, and 3 cuneiform bones.
Metatarsals (5) — Long slender bones, similar to the ones of the hand.
Talus — Aka. the ankle bone. Between the heel bone, tibia and fibula.
Phalanges (14) — Aka digits. 2 in each big toe and 3 in each smaller toe.

Terms

Osteology — the study of bones

Muscular System

Some of the muscular system’s functions are mobility, circulation, digestion, stability and posture. There are more than 650 muscles in the body and there are 3 types of muscles:

Cardiac muscle — Type of striated muscle only found in the heart.
Involuntary muscle (nonstriated) — Controlled by the autonomic nervous system. Controls functions like breathing and digestion.
Voluntary muscles (striated) — Muscles that we can control.

A muscle has 3 parts:

Origin — Part of the muscle that does not move and is anchored to the bone. Attached closest to the skeleton.
Belly — Middle part of the muscle.
Insertion — Movable part of the muscle anchored to the bone. Attached farthest from the skeleton.

Muscle tissue can be stimulated by:

Massage
Electric current therapy
Infrared light
Dry heat
Moist heat
Nerve impulses
Chemicals

Scalp and Neck Muscles

Frontalis — Front portion of the epicranius. Scalp muscle that raises the eyebrows, draws the scalp forward, and causes wrinkles across the forehead.
Occipitalis — Back portion of the epicranius. Draws the scalp backward.
Epicranius — Aka. Occipitofrontalis. Broad muscle that covers the top of the skull and consists of the occipitalis and frontalis.
Epicranial aponeurosis — Tendon that connects the occipitalis and frontalis
Platysma — Broad muscle extending from the pectoral and deltoid muscles to the side of the chin. Lowers the lower jaw and lip.
Sternocleidomastoideus — neck muscle that lowers and rotates the head. Originates at the clavicle and inserts and the temporal bone near the ear.

Face, Nose, and Mouth Muscles

Corrugator — Small muscle between the eyebrows below the frontalis. Draws the eyebrow down and wrinkles the forehead vertically.
Temporalis — Located near the temple. It opens and closes the jaw.
Orbicularis oculi — Ring muscle of the eye socket that closes the eyelids and helps pumps tears.
Levator labii superioris — Muscles that surrounds and elevates the upper lip and dilates the nostrils.
Zygomaticus major — Muscle that extends from the zygomatic bone to the angle of the mouth. Directs the lip outward and upward when laughing or smiling.
Zygomaticus minor — Muscle that works with the zygomaticus major to make facial expressions.
Masseter — Located at the lower part of the zygomatic. Moves the mandible, causing the mouth to close.
Buccinator — Located at the upper and lower jaw. Compresses the cheeks and expells air between the lips.
Triangularis — Located at the corner of the lip that extends over the chin. Pulls down the corners of the mouth when frowning.
Depressor labii interioris — Muscle that surrounds and lowers the lower lip and draws it to one side like to expresses sarcasm.
Procerus — Muscle that covers the bridge of the nose. Lowers the eyebrows and causes wrinkles across the bridge of the nose.
Levator palpebrae superioris — Thin muscle that controls the movement of the eyelid.
Levator anguli oris — Muscle that raises the angle of the mouth and draws it inward.
Risorius — Muscle at the corner of the mouth that draws it out and back when grinning.
Orbicularis oris — Muscle that circles the mouth. Contracts, puckers, and wrinkles the lips.
Mentalis — Muscle at the top of the chin that elevates the lower lip and raises and wrinkles the skin of the chin.

Shoulder and Arm Muscles

Trapezius — Covers the back of the neck as well as the upper and middle regions of the back. Lifts and turns he head, raises the shoulders, control swinging movements of the arm.
Deltoid — Large muscle covering the shoulder joint that allows the arm to extend outward and to the side of the body.
Bicep — Front of the upper arm. Lifts the forearm and flexes the elbow.
Supinator — Forearm muscle that rotates the radius outward and the palm upward.
Pronator — Muscle that turns the hand inward, so the palm faces downward.
Flexor — Extensor muscle of the wrist involved in flexing or bending it.
Tricep — Muscle covering the entire back of the upper arm that extends the forearm and straightens the elbow.
Extensors — Muscles that extends and straightens joints like the wrist, hand, and fingers to form a straight line.

Hand Muscles

Adductors — Muscles that draw a body part toward the midline of the body. Draw the fingers together in the hand.
Abductors — Muscles that draw a body part away from the midline of the body. Separate the fingers in the hand.
Opponens — muscle that allows the thumb to be moved toward a finger of the same hand.

Lower Leg and Foot Muscles

Peroneus longus — Muscle that covers the outer side of the calf. Inverts the foot and turns it outward.
Peroneus brevis — Muscle that is on the lower surface of the fibula and bends the foot down and out.
Extensor hallucius longus — Muscle that extends the big toe and flexes the foot.
Gastrocnemius — Muscle attached to the lower rear surface of the heel that pulls the foot down.
Tibialis anterior — Muscle covering the front of the shin that bends the foot upward and inward.
Soleus — Muscle that originates at the upper portion of the fibula and bends the foot down.
Flexor digiti minimi — Foot muscle that moves the little toe.
Abductor digiti minimi — Foot muscle that allows the little toe to flex and move.
Abductor hallucis — Foot muscle that moves the big toe away from the other toes.
Flexor digitorum brevis — Foot muscle that flexes the toes and helps maintain balance while walking and standing.

Nervous System

Neurology is the study of the structure, function, and pathology of the nervous system.

Nervous System Divisions

Autonomic Nervous System (ANS) — Controls involuntary muscle action and regulates the action of the smooth muscles, glands, blood vessels, heart and breathing.
Central Nervous System (CNS) — Controls voluntary muscle actions and consists of the brain, spinal cord, spinal nerves, and cranial nerves. Allows you to taste, smell, see, hear, think, breath, move, run, sleep, remember, sing, laugh, and write.
Peripheral Nervous System (PNS) — Connects the peripheral (outer) parts of the body to the central nervous system. Has both sensory and motor nerves. Carries impulses to and from the CNS.

The Brain and Spinal Cord

The brain controls all the body’s functions, the cranium protects it. The spinal cord originates in the brain and extends to the bottom of the spine, it’s protected by the spinal column. There are 31 pairs of spinal nerves that extend from the spinal cord to the muscles, organs, and skin.

Nerves

Nerves are white-ish nerve fibers that transmit impulses. They originate in the brain and spinal cord and branches to all parts of the body. There are 2 types of nerves:

Sensory nerves — Aka. Afferent nerves. Carry messages from the sense organs (heat, cols, sight, sound, smell, taste) to the brain and spinal cord.
Motor nerves — Aka. Efferent nerves. Carry impulses from the brain to the muscles or glands. Produces movement.

The simplest form of nervous activity that includes both nerves is called a reflex, which is a reaction to an outside stimulus.

Circulatory System

Aka. The cardiovascular system or vascular system.

The Heart

The heart is a cone shaped organ that keeps blood moving within the circulatory system. There are two systems of circulation:

Pulmonary circulation — carries oxygen-poor blood to the lungs for oxygenation and waste removal then returns that blood to the heart (left atrium) so that oxygen-rich blood can be delivered to the body.
Systematic circulation — Aka. General circulation. Carries oxygen-rich blood from the heart throughout the body and returns oxygen-poor blood back to the heart.

Blood Vessels

Blood vessels are tubelike structures that circulate blood throughout the body. These are the different types of vessels and their functions:

Arteries — Thick flexible tubes that carry oxygenated blood away from the heart to the arterioles.
Aorta — Largest artery in the body.
Arterioles — Small arteries that deliver blood to capillaries.
Capillaries — Tiny blood vessels that connect the smaller arteries to the venules, bring nutrients to the cells, and carry away waste materials.
Venules — Small veins that connect to capillaries to larger veins.
Veins — Thin blood vessels that are less elastic than arteries and carry blood containing waste to the heart and lungs for cleaning and to pick up oxygen. Contain valves to keep blood flowing in one direction to the heart to prevent blood from flowing backwards.

The Blood

Blood supplies oxygen and nutrients to cells and removes carbon dioxide and waste from them. Blood also:

Carries water, oxygen, and food to all cells and tissues.
Carries carbon dioxide and waste that is eliminated though the lungs, skin kidneys, and large intestine.
Equalizes body temperature.
Works with the immune system to protect the body from harmful toxins and bacteria.
Seals leaks from injured vessels by forming clots to prevent blood loss.

Head, Face and Neck Arteries

External carotid artery — Supplies blood to the front parts of the scalp, ear, face, neck, and sides of the head.
Internal carotid artery — supplies blood to the brain, eyes, eyelids, forehead, nose, and internal ear.
Common carotid arteries — main arteries on both sides of the neck that supply blood to the head, face, and neck.

Head, Face and Neck Veins

External jugular vein — Located at the side of the neck. Carried blood returning to the heart from the head, face, and neck.
Internal jugular vein — Located at the side of the neck. to collect blood from the brain and parts of the face and neck.

Lymphatic System

Lymph is a clear/pale yellow fluid that has white blood cells and travels through lymph vessels. Lymph nodes are gland-like structures that filter bacteria, viruses, and cancer cells and are connected by lymph vessels. The system’s primary functions are:

Carry nourishment from the blood to the cells.
Defend against toxins and bacteria and remove by-products of infection, like pus and dead tissue.
Remove waste from the cells to the blood.
Provide suitable fluid environment for the cells.

Integumentary System

The word integument means natural covering. The skin protects the body from outside elements like germs and chemicals. It is also resistant to water and regulates body temperature.

Endocrine System

Glands produce and release substances that perform a specific function in the body. There are 2 main types of glands:

Endocrine glands — Aka. Ductless glands. Includes the pituitary, thyroid, and adrenal glands. Releases hormones directly into the bloodstream.
Exocrine glands — Aka. Duct glands. Sebaceous glands, sudoriferous glands and more. Produces a substance that travel through small tube-like ducts.

Hormones are chemical substances like insulin, adrenaline, and estrogen that stimulate activities in the body. Changes in hair growth or shedding may indicate an imbalance in the endocrine system.