Integumentary System: Exam 2 Study Guide

• Study guide for Exam 2
• Covers Chapters 5-8
• No diagrams will be on the lecture exams, diagrams will be on the lab exams

Integumentary System - Chapter 5

• The epidermis consists of keratinized stratified squamous epithelium.
• Keratinocytes are the most common cells in the epidermis.
• Keratin is a tough fibrous protein that protects the skin.
• Melanocytes protect skin from ultraviolet light damage.
• Melanin is a pigment that protects DNA skin cells from UV radiation by absorbing rays.
• Dendritic (Langerhans) cells are macrophages that ingest foreign substances and activate the immune system.
• Tactile (Merkel) cells are sensory receptors for touch.
• Types of tactile cells include:
• Free nerve endings
• Merkel cells
• Meissner's corpuscles in the dermal papillae
• Pacinian corpuscles in the reticular layer of the dermis
• Layers of the epidermis from superficial to deep:
• Stratum corneum
• Stratum lucidum
• Stratum granulosum
• Stratum spinosum
• Stratum basale
• Stratum lucidum is missing from thin skin. Thick skin contains stratum lucidum
• Cells in the stratum basale are a single row of keratinocyte stem cells undergoing mitosis.
• The stratum spinosum contains melanin granules and dendritic cells.
• The stratum granulosum has 1-5 layers of epidermal cells where keratinocyte appearance changes drastically.
• The stratum corneum has 20-30 layers of keratinized epithelial cells.
• The stratum corneum makes up three-quarters of the epidermis thickness.
• Constant sun exposure leads to friction and callus formation in the stratum corneum
• The dermis consists of connective tissue with collagen and elastic fibers
• The dermis is vascular.
• The dermis has a papillary and reticular region.
• The papillary region contains loose areolar connective tissue.
• The reticular region contains dense irregular connective tissue and scattered adipose tissue.
• Carotene provides a yellow to orange pigment found in plant foods like carrots.
• Carotene accumulates in the stratum corneum and adipose tissue
• Hemoglobin causes reddened skin called erythema, indicating fever, hypertension, inflammation, or allergy.
• Hemoglobin is a protein in an erythrocyte (RBC) that carries respiratory gases, like oxygen and carbon dioxide.
• Cyanosis is a lack of hemoglobin due to poorly oxygenated blood.
• Pallor, an unhealthy pale appearance, may signify anemia, low blood pressure, or shock.
• Jaundice, yellowing of the skin, may indicate a liver disorder.
• A bronze skin color indicates a metallic appearance and can be a sign of Addison's disease.
• A bruise indicates blood has escaped from circulation and clotted beneath the skin.
• The hypodermis is also known as the subcutaneous layer.
• The hypodermis consists of loose areolar connective tissue and adipose tissue.
• The hypodermis is deep to the dermis, and not technically part of the skin.
• Hair consists of flexible strands produced by hair follicles.
• Hair contains dead keratinized epidermal cells.
• The hair shaft is the portion of hair in which keratinization is complete.
• The hair root is where keratinization is still ongoing, deep within the follicle.
• A hair root plexus is a knot of sensory nerve endings surrounding the hair follicle.
• The three layers of hair are:
• Medulla
• Cortex
• Cuticle
• The medulla is the core with large cells and air spaces, absent in fine hairs.
• The cortex is a bulky layer surrounding the medulla and consists of flattened cells.
• The cuticle is the outermost layer formed by a single layer of cells that overlap like shingles on a roof.

Hair Follicles

• Cells fold down from the epidermal surface into the dermis
• The hair bulb is the deep end of the hair follicle, surrounded by a hair follicle receptor, or root hair plexus.
• The hair papilla is the center of the hair bulb containing capillaries and nutrients for growth.
• The hair matrix is the actively dividing area of the hair bulb that produces hair.
• A reduction in cell division causes hair loss
• The arrector pili muscle causes the hair to stand up straight (piloerection), causing goosebumps when contracted.
• The 2 types of hair humans have throughout their lifetime are:
• Vellus
• Terminal
• Vellus hair is fine nonpigmented hair found in children and adult females.
• Terminal hair is course hair found as longer hair of the eyebrows and scalp.
• Nails are a scalelike modification of the epidermis that forms a clear surface of the distal finger or toe.
• The 3 regions of a nail are:
• Free edge
• Nail plate or body
• Proximal root
• The nail bed is the deepest layer of the epidermis.
• The nail matrix is part of the nail and responsible for nail growth.
• The cuticle is a skin fold around the nail.

Glands of the Skin

• Sweat glands are called sudoriferous glands.
• Types of sudoriferous glands include:
• Eccrine or merocrine glands
• Apocrine glands
• Ceruminous glands
• Mammary glands
• Eccrine or merocrine glands function in thermoregulation, excrete waste products and are numerous excluding the axillary and anogenital region.
• Apocrine glands function at puberty under hormonal influence, contribute to odor, and are located in the axillary and anogenital region.
• Ceruminous glands are modified sweat glands that secrete earwax in the axillary region and the anogenital region.
• Mammary glands are modified sweat glands that secrete milk.
• Oil glands are called sebaceous glands and produce oil (sebum).
• Sebum protects against bacterial growth, water loss, and inhibits bacterial growth, it is a mixture of triglycerides, cholesterol, proteins, and inorganic salts.
• Sebum is released into the hair follicles.
• Acne is inflammation of sebaceous glands caused by bacteria which thrive in the lipid-rich sebum.

Integumentary system functions

• Protection
• Thermoregulation
• Cutaneous sensation
• Metabolic functions
• Blood reservoir
• Excretion
• The integumentary system offers chemical, physical, and biological protection.
• Chemical protection occurs via the acid mantle, skin secretions, and melanin.
• Physical protection is keratin protection in keratinized stratified squamous epithelial cells.
• Biological protection comes from the immune system from dendritic (Langerhans) cells and macrophages in the dermis.
• Thermoregulation occurs via eccrine sweat glands producing sweat.
• Sensible perspiration is sweat visible on the skin as drops.
• Insensible perspiration is sweat that evaporates immediately from the skin.
• The integumentary system cools the body via dermal blood vessels that dilate.
• Dermal blood vessels constrict to retain heat keeping blood in deeper tissues and skeletal muscles can contract to generate heat for the body.

Cutaneous Sensation

• The integumentary system exhibits cutaneous sensation.
• Receptors for cutaneous sensation include:
  • Merkel cells in the epidermis
  • Meissner's corpuscles
  • Free nerve endings in the dermal papillae
  • Pacinian corpuscles in the reticular layer of the dermis which are activated by deep pressure
• Metabolic functions include:
  • Vitamin D requires activation of a precursor molecule in the skin by UV light.
  • It is produced from cholesterol
• The integumentary system functions as a blood reservoir.
• Dermal vascular supply holds about 5% of the body's entire blood volume.
• The integumentary system excretes water, electrolytes, fatty acids, lactic acid, and nitrogen compounds (ammonia, urea, and uric acid).
• The 3 types of skin cancers are basal cell carcinoma, squamous cell carcinoma, and melanoma.
• Basal cell carcinoma is the least malignant, most common, and does not metastasize.
• Squamous cell carcinoma is the second most common type of skin cancer.
• Melanoma is the most severe type of skin cancer and will readily metastasize.
• The ABCDE rule determines if a blemish on the skin suggests you should see a doctor.
• A stands for Asymmetry; check if two sides of the pigmented spot or mole do not match.
• B stands for Border irregularity, determining if the borders of the lesion exhibit indentation.
• C stands for Color; check if the pigmented spot contains several colors.
• D stands for Diameter, determines if the spot is larger than 6 mm in diameter.
• E stands for Evolving, to determine if a spot or mole is changing in size, shape, or color.
• A burn is tissue damage caused by heat, electricity, radiation, or chemicals.
• The Rule of Nines divides the body into 11 sections with each section representing 9% of body surface (except genitals, which account for 1%).
• Partial thickness burns are first or second-degree burns.
• A first-degree burn damages only the epidermis.
• A second-degree burn damages the epidermis and dermis.
• Second-degree burns cause blisters due to fluid filled pockets between the epidermis and dermis.
• Full thickness burns are third-degree burns.
• A third-degree burn means the entire skin thickness is burnt, no edema, and no initial pain because nerve endings are destroyed.
• The first major threat with burns is dehydration due to an extreme loss of fluids.
• Infection is the leading cause of death for burn patients.
• Psoriasis is a chronic autoimmune condition with raised, reddened epidermal patches covered with silvery scales that itch or burn, crack, and sometimes bleed or become infected.
• Albinism is an inherited condition in which melanocytes do not synthesize melanin.
• Alopecia is the absence of hair from areas where it would normally occur.
• Boils and carbuncles mean inflammation of hair follicles and sebaceous glands in which an infection has spread to underlying cutaneous tissue.
• Cold sores (fever blisters) are small fluid-filled blisters that itch or hurt.
• Rosacea is a chronic skin eruption produced by dilated small blood vessels of the face, particularly the nose and cheeks.

Bones and Skeletal Tissues - Chapter 6

• The 3 types of cartilage are:
• Hyaline
• Elastic
• Fibrocartilage
• Hyaline cartilage is located at articular surfaces, costal joints that join ribs to the sternum, respiratory cartilages which include the thyroid and cricoid cartilage ,and tracheal cartilage .
• Elastic cartilage is located in the external ear and epiglottis.
• Fibrocartilage is located in the Meniscus, intervertebral disc, and pubic symphysis.
• Cartilage grows via appositional and interstitial growth
• Appositional growth secretes new matrix on the external face of existing cartilage tissue (bones increasing in diameter/width).
• Interstitial growth divides lacunae-bound chondrocytes and it secretes a new matrix within (bones increasing in length at epiphyseal plate).
• The functions of bones are:
• Support
• Protection
• Movement
• Mineral and growth factor storage
• Blood cell formation
• Triglyceride storage
• Hormone production
• The skeletal system provides support via the axial skeleton, which provides a framework that supports the body and cradles soft organs.
• The skeletal system protects via the axial skeleton:
• Cranial bones protect the skull
• Vertebrae surround the spinal cord
• The rib cage protects vital organs of the thorax.
• The skeletal system helps facilitate movement via the appendicular skeleton which attaches to skeletal muscles ,anchors the bones and acts as levers to enable body movement.
• The skeletal system stores minerals and growth factors.
• Calcium
• Phosphate
• Lipids (fat) are stored in bone cavities.
• Osteocalcin helps to regulate insulin secretion.
• Flat bones are thin, flattened and usually a bit curved and include the:
• sternum
• scapulae
• ribs
• most skull bones
• Irregular bones are complex, asymmetrical and do not fit into any other category. Examples are vertebrae, and coxal (hip bones).
• Short bones are roughly cube shaped e.g. sesamoid (patella), carpals (wrist), and tarsals (ankles).
• Long bones are longer than they are wide and include the:
• Humerus
• Ulna
• Radius
• Metacarpals
• Phalanges (fingers)
• Femur
• Tibia
• Fibula
• Metatarsal
• Phalanges (feet)
• The 2 types of bone are compact and spongy.
• Compact bone is the dense outer layer of every bone that appears smooth and solid (also referred to as lamellar bone).
• Spongy bone is trabecular or woven contains an irregular latticework.
• The diaphysis is the shaft of the bone that forms the long axis of the bone which contains the marrow cavity.
• The epiphysis is the expanded end of long bone ends that articulates with other bones.
• The epiphyseal plate is the layer of hyaline cartilage that allows the diaphysis to grow in length.
• The epiphyseal line is the remnant of the epiphyseal plate and it's located between the epiphysis and the diaphysis.
• The periosteum is the fibrous double layered outer membrane covering the surface of a bone and is involved in making the bone grow in width.
• Sharpey's (perforating) fibers are collagen fibers that anchor the periosteum's fibrous layers to the bone.
• The nutrient foramen is the opening in the periosteum of nerve fibers and blood vessels.
• The endosteum is the inner membrane that lines the marrow cavity and covers the trabeculae.
• Hematopoietic tissue is red marrow found in the medullary cavity that becomes yellow as we age.
• Bone markings provide sites of attachment for muscles, ligaments, and tendons, joint surfaces, and openings for blood vessels and nerves.
• There are 3 different groups of bone markings:
• Projections
• Joint Projections
• Depressions and Openings

Bone Markings

• A tuberosity is a large, rounded projection (e.g., ischial tuberosity).
• A crest is a prominent narrow ridge on a bone (e.g., iliac crest)
• A trochanter is a very large, blunt, irregularly shaped process (e.g. greater and lesser trochanter).
• A line is a narrow ridge of bone (e.g. intertrochanteric line).
• A tubercle is a small rounded projection or process (e.g. adductor tubercle).
• An epicondyle is a raised area on or above a condyle (e.g. medial epicondyle).
• A spine is a sharp, slender, often pointed projection (e.g. ischial spine).
• A process is any bony prominence (e.g. spinous process).
• The head of the bone is a bony expansion carried on a narrow neck (e.g. head of rib).
• A facet is a smooth, nearly flat articular surface (e.g. facet of rib).
• A condyle is a rounded articular projection (e.g. mandibular condyle).
• A ramus is an armlike bar of bone (e.g. mandibular ramus).
• A groove is a furrow (e.g. mandibular groove).
• A fissure is a narrow, slit-like opening (e.g. superior orbital fissure).
• A foramen is an opening or hole in a bone for blood vessels, nerves, and ligaments (e.g. foramen magnum).
• A notch is an indentation at the edge of a structure (e.g. lesser sciatic notch).
• A meatus is a tube-like passageway in a bone (e.g. external acoustic meatus).
• A sinus is a cavity within a bone, filled with air and lined with mucous membrane (e.g. frontal sinus).
• A fossa is a shallow, basin-like depression, often serving as an articular surface (e.g. olecranon fossa).
• The three important bone cells are:
• Osteoblasts
• Osteoclasts
• Osteocytes
• Osteoblasts are bone-forming cells that secrete bone matrix and are responsible for calcium deposition.
• Osteocytes are "spider-shaped" mature bone cells.
• Osteocytes regulate bone remodeling, maintain calcium and phosphate homeostasis, and preserve the bony matrix.
• Osteoclasts are bone dissolving cells responsible for bone resorption.
• Osteoclasts secrete lysosomal enzymes that break down the organic matrix and acids that convert calcium salts to a soluble form for removal.
• The osteon or Haversian system is the structural unit of compact bone that contains tubes of bone matrix referred to as lamella and is organized along lines of stress.
• Lamellae are aligned parallel to the axis of the bone.
• Lacunae are cavities or spaces in the compact bone structure that houses the osteocytes.
• Canaliculi are tiny canals to connect osteocytes to transport nutrients and waste to and from the cells.
• The central canal (or Haversian canal) contains blood vessels in the center of an osteon, that provide blood vessels and nerves to the bone.
• Perforating canals (or Volkmann's canals) lie at right angles to the central canals, allowing blood vessels to enter the bone from the periosteum.
• Osteoid is the organic part of the matrix produced by osteoblasts.
• Ossification is the term for bone growth and bone development.
• The 2 types of ossification that occur during prenatal bone development are endochondral and intramembranous ossification.
• During endochondral ossification, bone develops replacing hyaline cartilage model in fetal development.
• Forms all bones below the base of the skull except clavicle.
• The primary ossification center is in the diaphysis, and the secondary ossification center is in the epiphysis.
• The bone collar forms at the beginning of endochondral ossification around the diaphysis.
• During intramembranous ossification, bone develops from a fibrous membrane.
• Forms flat cranial bones of the skull and clavicles.
• Postnatal bone growth occurs during infancy and youth (interstitial bone growth that occurs at the epiphyseal growth).
• The epiphyseal plate transforms and is replaced by bone cells.
• Bone remodeling involves bone deposition and bone resorption processes.
• New bone is created and mineralized by osteoblasts.
• Bone remodeling is triggered by mechanical signals (exercise and gravitational forces) and blood calcium levels.
• Osteoblast activity facilitates bone deposition.
• The hormone calcitonin, from the thyroid gland, stimulates osteoblast activity.
• Osteoclast activity cause bone resorption.
• The hormone PTH, from the parathyroid gland, stimulates osteoclast activity.
• Fracture is the term for a break in a bone.
• A simple or closed fracture occurs when the broken bone doesn't penetrate the skin.
• A compound or open fracture occurs when the broken bone penetrates the skin.
• A comminuted fracture occurs when the bone fragments into three or more pieces.
• A compression fracture occurs when the bone is crushed.
• A spiral fracture occurs when ragged breaks occur when excessive twisting forces are applied to the bone.
• An epiphyseal fracture is the epiphysis separates from the diaphysis along the epiphyseal plate.
• A depressed fracture occurs when a broken bone portion is pressed inward.
• A greenstick fracture occurs when the bone breaks incompletely, similar to the way a green twig breaks.

Steps of Bone Repair

1. Hematoma forms.

• Blood vessels are torn and hemorrhage (mass of clotted blood forms at the fracture site)

2. Fibrocartilaginous callus forms

• Soft callus (including newly formed collagen fibers) splints the broken bone.

3. Bony callus forms

• New trabeculae appear and convert fibrocartilaginous callus to bony (hard) callus

4. Bone remodeling occurs.

• Excess material is removed, and compact bones re laied down to reconstruct shaft walls.
• Osteomalacia is a disease where the bones are poorly mineralized.
• Rickets is a disease recognized by bowed legs and deformities of the pelvis in children; the children's version of osteomalacia.
• Osteoporosis is when bone resorption outpaces bone deposition causing overall bone mass to be reduced; the major cause is decrease in estrogen levels.
• Paget's Disease is excessive and haphazard bone deposit and resorption.
• The skeleton consists of bones, cartilages occur in isolated areas, joints and ligaments that connect bones and reinforce joints.
• There are 206 bones in the skeleton.
  • 80 bones are in the axial skeleton
  • 126 bones are in the appendicular skeleton.
• The axial skeleton consists of the skull, vertebral column, and thoracic cage.
  • Forms longitudinal axis of the body
  • Supports head, neck, and trunk
  • Protects brain, spinal cord, and organs in thorax.
• There are 22 bones in the skull.
• There are 8 cranial bones that:
• Enclose and protect the fragile brain
• Provide attachment sites for the head and neck muscles.
• The cranial bones are:
• Frontal (1)
• Parietal (2)
• Temporal (2)
• Sphenoid (1)
• Ethmoid (1).
• The frontal forms the forehead contains paranasal sinuses.
• The parietal bones form the superior and lateral aspects of the skull.
• The occipital bone forms the posterior aspect and most of the base of the skull. The occipital bone's markings are the foramen magnum, occipital condyles, and external occipital protuberance.
• The temporal bone forms the temple of the skull. The temporal bone markings are the zygomatic arch, mandibular fossa, external acoustic meatus, mastoid process, and styloid process.
• The sphenoid bone is the keystone of the cranium and contains paranasal sinuses.
• The sphenoid bone markings are the sella turcica, optic canals, greater wings, and lesser wings.
• The ethmoid bone forms part of the nasal septum and lateral walls and roof of the nasal cavity and contains paranasal sinuses.
• There are 14 facial bones that:
  • Form framework of the face
  • Contain cavities for special senses
  • Provide openings for air and food passage
  • Secure the teeth
  • Anchor facial muscles of expression.

Facial Bones

• Nasal (2); forms the bridge of nose

• Lacrimal (2); forms part of the medial orbit wall

• Zygomatic (2); forms the cheek and part of the orbit

• Inferior nasal concha (2); forms part of the lateral walls of nasal cavity

• Mandible (1); lower jaw with teeth attached

• Maxilla (2); upper jaw with teeth attached, contains paranasal sinuses

• Palatine (2); posterior part of the hard palate

• Vomer (1); inferior part of the nasal septum

• The Bones that form the eye orbits are:

  • Frontal
  • Ethmoid
  • Lacrimal
  • Sphenoid
  • Maxilla
  • Zygomatic

• The major sutures are:

  • Coronal
  • Sagittal
  • Squamous
  • Lambdoid

• The coronal suture connects the frontal and two parietal bones.

• The sagittal suture connects the two parietal bones.

• The lambdoid suture connects the occipital and parietal bones.

• Fontanelles are "soft spots" or membranous area between cranial bones in a fetus or newborn baby's skull. Fontanelles are:

  • Anterior
  • Posterior
  • Sphenoidal
  • Mastoid

• The hyoid bone does not articulate with any other bone, as it is attached to cervical vertebrae with ligaments

• There are 26 irregular bones found within the vertebral column

• There are 7 cervical vertebrae. Markings found on this vertebrae are:

  • Intervertebral foramen for blood vessels
  • Spinal cord
  • Pedicle
  • Spinous process
  • Transverse foramen in the cervical region

• The name for C1 is the Atlas:

  • Its vertebra does not have a body .
  • Allows you to move your head up and down

• The name for C2 is the Axis:

• vertebra has a den (odontoid process)

• Allows for the atlas and skull to rotate the head

• There are 12 thoracic vertebrae:

• Has a den (odontoid process).

• Articulates with ribs at rib tubercles

• There are 5 lumbar vertebrae: -Provides the Thickest body because it does the most weight bearing

• There 5 fused vertebrae in the sacrum:

• Sacroiliac joint to articulate with hips

• There 4 fused vertebrae in the coccyx:

  • The tailbone that is located at the base of the vertebral column that contains four unattached vertebrae

• Intervertebral discs

• Absorb shock via tissue between the vertebral bodies.

• The intervertebral dics are .

• A herniated disc is a condition that occurs when a disc is squeezed out of the intervertebral space to push on radiating nerves

• The 2 types of vertebral curvatures are:

  • Primary
  • Secondary

• Primary curvatures are thoracic and sacral that is Both are convex.

• Secondary curvatures are cervical and lumbar that areBoth are concave".

• The sternum is the breast bone:

  • Is located the manubrium
  • The middle main region of the sternum that is the body

• And is the Xiphoid process

• Most ribs connects to sternum and makes up most the thoracic cage

• There 12 pair of ribs that connect together to the thoracic cage

• There 7 pairs of true ribs:

• attached to the sternum via the costal cartilage".

• There are 5 pairs of false ribs

• Where the last pairs are floating that are have no attachement to the sternum

• There is no constal cartilage where floating ribs are located

• Functions to protect vital organs

• There floating ribs on each side

• there found 11-12"

• The scapula and clavicle make up the perctoral (shoulder) girdle

• The bones include

  • coracoid process
  • Acr"

• The scapula are shoulder joint glenoid cavity that allows for the head of the humerus to fit

• The clavicle is a long and curved bone

  • It is connected to the acromion. -And sternum

•   radius, ulna, carpals metacarpals that has a joint
    glenoid.
  

Bones of the Limbs

• The humerus has a head that articulates with the glenoid cavity (fossa) of the scapula.
• The humerus' bone markings are head, greater and lesser tubercle.
• The radius is the lateral bone in the antebrachial region on the thumb side and articulates with the wrist bones.
• The ulna is the medial bone in the antebrachial region on the pinky side.
• The ulna markings are olecranon process with olecranon fossa of the humerus.
• The carpals are
  • The pisiform, trapezium, trapezoid, capitate, hamate are for the wrist.
• There are 5 metacarpals.
• There are 14 phalanges. There 2 in the thumb (proximal and distal phalanx). The #2-5 are (proximal, middle, & distal digits"
• The pelvic girdle is made
• The pelvic includes an Ilium that superiory connects bone.And The Pubis (medially connected)
• The ilium is the most superior bone of the pelvis
• And what are those bone pelvis: ischium
• most anterior of the pelvic -"Females has are largers."
• The iliac is a bone that has a crest on its surface. Also, it has acetobulum/ of obturator
• Bone Femur , of tibia, fibula tarsals, metatarsals, and phalanges - ""Head connects "acetabulum ( largest) "" Connects to the Tibia There the 8 main area bones

the Metatarsals long bones (5 Metatarsals long) are also located

Also there are the Toe which digitize. And digits 2 &5

• Abnormal In Curvature
• What one is related to the Scoliosis curve?
• thoracic = kyphosis
• "Point of articulation between bones"
• is how "points" that bone "meet"

Joints. (chapter: 8)

• They are name After name of bone

• structure include:

  • Fibrous
  • Cartilaginous
  • synovial

• functionality of the skeletal" = Syna-,amphi-, - all types & -arthrotic

There are 2 main kinds of skeletal cavities:

• One with a fluid filled- Synovial cavity

• One is the bone without a fluid filled system - either one: Fibrous or Catilaginous

• bones tissues are made by CT

• ""Syna- ""

  • The joints is bones

Sutures -Gomphoses"

= ligamnets = Bones ligamenented by bone that have CT"

""cartilaginous Joint between Manibrium/RIb

• "Movement"" "Amp-"- th-" joint

• Joint

  • It have articular that has:

• synovial -"ligaments"

• Bone

lig"and There there those kinds/ catagories": ""NonAxial" A iala , And There

• glide is used to move the bone on surface" ""

bones for the joint surfaces! "" Metacarpals""