A&P Flashcards
Gross (Macroscopic) Anatomy
The study of large body structures visible to the naked eye
Types of Gross Anatomy
- Regional Anatomy: All the structures (e.g., muscles) in a particular region of the body such as the abdomen
- Systemic Anatomy: Body structure is studied system by system (e.g., cardiovascular system)
- Surface anatomy: The study of internal structures as they relate to the overlying skin surface
Microscopic Anatomy
The study of body structures that can’t be seen with the naked eye
Types of Microscopic Anatomy
- Cytology Anatomy: The study of the cells of the body
-Histology: The study of tissues
Developmental Anatomy
- The study of the structural changes that occur throughout the life span
Type of developmental anatomy
- Embryology: The study of developmental structural changes that occur before birth
Types of Specialized Anatomy
- Pathogical Anatomy: Study of structural changes caused by disease
-Radiographic Anatomy: Study of structures viewed by x-ray or another type of device
Complimentarity of Structure and Function
The function always reflect the structure thus this is why anatomy and physiology is studied together
Levels of Organization
- chemical level: Atoms combine to form molecules (e.g., water)
- cellular level: molecules form organelles which compose cells
- Tissue level: Groups of similar cells (epithelial tissue, muscle tissue, connective tissue, and nervous tissue)
- organ level: Organs are made up of two to four different types of tissue to make complex functions possible
- organ system level: organs that work together to accomplish a common purpose form an organ system (e.g., cardiovascular system)
Negative feedback mechanism
-The output/response shuts off or decreases the intensity of the initial stimulus
-variable changes to the opposite of the initial change so it’s back to normal
Positive feedback mechanism
-output/response enhances the initial stimulus so that further responses are greater
-variable proceeds the same direction as the initial change so it deviates further from normal bf
Superior/cranial
-above
-towards the head end or upper part of a structure or the body
Inferior/caudal
-below
-away from the head end or towards the lower part of a structure or the body
Anterior/ventral
-in front of
-towards or at the front of the body
posterior/dorsal
-behind
-towards or at the back of the body
medial
-on the inner side of
-towards or at the midline of the body
lateral
-away from the midline of the body
-on the outer side of
intermediate
-between a more medial and lateral structure
proximal
-closer to the origin of a body part or to the point of attachment of a limb to the body trunk
distal
-farther from the origin of a body part or to the point of attachment of a limb to the body trunk
superficial/external
-towards or at the body surface
Deep/internal
-away from the body surface, more internal
sagittal plane
-vertical plane dividing the body into left and right parts
Midsagittal plane
A saggital plane that lies directly in the mid line of the body
Parasaggital plane
A sagittal plane offset from the midline
Frontal (coronal plane)
A vertical plane that divides the body into anterior and posterior
Transverse plane
A horizontal plane that dives the body into superior and inferior
Dorsal Body Cavity
-protects nervous system organs
-cranial cavity (containing brain)
-vertebral cavity (contains spinal cord)
-
Ventral Body Cavity (come back)
- contains internal organs collectively called viscera
Thoracic cavity
Epidermis
- composed of epithelial cells
-outermost protective shield of the body
-avascular
Dermis
-composes the bulk of skin
-composed of dense, fibrous connective tissue
-vascular
Subcutaneous tissue/hypodermis
-consists mainly of adipose tissue
-stores fat and anchors the skin to underlying structures (mostly muscles) but loose enough so that the skin can glide
-acts as a shock absorber and insulator to reduce heat loss
Keratinocytes
-produce fibrous protein
-composed most of the epidermal cells
-tied together by desmosomes for strength and tight junctions in some layers to hinder water movement
-undergo continuous mitosis in response to epidermal growth factor, and newly formed cells are pushed upwards while filling with keratin
-most superficial later of epidermis if dead keratinocytes
-with skin friction, cell production and keratin formation accelerated
-persistent skin friction = thickening of epidermis called callus
Melanocytes
-melanin is made in membrane-bound granules called melanosomes and then transferred to nearby keratinocytes
-therefore, basal keratinocytes have more melanin than melanocytes
- melanin clusters on the superficial of the keratinocyte nucleus forming pigment shield that protects nucleus of the cell
-spider shaped
dendritic cells/langerphans
-star shaped macrophages
-derived from bone marrow and migrate to epidermis
-key activators of immune system
-forms a network around the keratinocytes
Tactile cells/Merkel cells
-sensory receptors for touch
Layers of the epidermis
-thick skin (covers areas subject to abrasion such as palms, fingertips and soles of the feet and consists of 5 layers/strata)
-thin skin (covers the rest of the body ad doesn’t have stratum lucid layer)
-Deepest to superficial:
-stratum basale, stratum spinosum (prickly layer), stratum granulosum (granular layer), stratum lucid (clear layer) and stratum corneum (horny layer
Stratum Basale/stratum germinativum
-deepest epidermis layer
-attached to the underlying dermis
-a single row of stem cells (youngest keratinocytes)
-each time one of the cells divide, one daughter cells journeys to the surface of epidermis and matures while others remain here to produce new keratinocytes
-10-25% of cells are melanocytes
Stratum spinosum (prickly layer)
-several layers thick
- Keratinocytes appear spikey, “prickle cells” under a microscope but only because of tissue preparation and their desmosomes as they don’t look like this in live cells
-keratinocytes, dendritic cells, and melanosomes exist here
-cells contain intermediate filaments with pre-keratin attached to desmosomes to resist tension in the cells
Stratum granulosum (granular layer)
- 4 to 6 layers thick and last layer of living cells since the cells above this layer are too far from the dermal capillaries to survive
-keratinzation occurs with
cells flattening and nuclei and organelles disintegrating
-also, the cells accumulate keratiohyaline granules that help form keratin fibers in upper layers and they Accumulate lamellar granules which are water resistant glycolipids
-therefore, cells are tough and water resistant here
Stratum lucidum (clear layer)
-only in thick skin
-clear layer because of how it is visible through the microscope
- composed of 2 to 3 layers of dead keratinocytes
Stratum Corneum (Horny layer)
- 20-30 rows of flat, anucleated, keratinized dead cells
- ¾ of epidermal thickness
= Protect deeper cells from the environment and Prevents water loss, abrasion, and penetration - Act as a barrier
Cells undergo apoptosis, controlled cell death and Slough off as dandruff
Papillary dermis (apart of dermis)
-Superficial layer of areolar connective tissue containing Loose, interlacing collagen and elastic fibers and blood vessels
-Phagocytes and other defensive cells patrol for microorganisms
-superficial region of dermal papillae (sends fingerlike projections into epidermis) - can contain capillary loops or free nerve endings (pain receptors) and touch receptors - in thick skin, they lie atop mounds called dermal ridges which then causes the overlying epidermis to form epidermal ridges (friction ridges)
Skeleton
-contains bones, cartilage, ligaments and joints
-initially made of cartilages and fibrous membranes but soon gets replaced with bone
-the cartilage that remains are in regions where flexible skeletal tissue is needed
Hyaline Cartilage
-looks like frosted glass when freshly exposed
-provide support with flexibility and resilience
-most abundant skeletal cartilage
-chondrocytes are spherical with fine collagen fibers in their matrix
-includes articular cartilage (covers the end of most bones at movable joints), costal cartilage (connects the ribs to the sternum), respiratory cartilage (forms the skeleton of the larynx and other respiratory passageways) and nasal cartilage (supports the external nose)
Elastic Cartilage
-look like hyaline cartilage
-contains more stretchy elastic fibers meant for repeated bending
-found in external ear and epiglottis
Fibrocartilage
-highly compressible and great tensile strength
-consists of parallel rows of chondrocytes with thick collagen fibers
-found in sites that are subject to both pressure and stretch (menisci (pad like cartilage in knee joint) and discs between vertebrae)
Two Ways for Cartilage Growth
-Cartilage has flexible matrix that can accomodate mitosis unlike the hard matrix of bone
-Appositional growth (cartilage forming cells in the surrounding perichondrium secrete new matrix against the external face of the existing cartilage tissue)
-Interstitial growth (lacunae-bound chondrocytes divide and secrete new
matrix, expanding the cartilage from within. and cartilage growth ends during adolescence when the skeleton stops growing)
Cartilage vs bone
Cartilage:
-Surrounded by perichondrium
-No blood vessels or nerves
(only in perichondrium)
-Chondrocytes in lacunae
-Flexible extracellular matrix
-Extracellular matrix made by chondroblasts
-Appositional growth and
interstitial growth
Bone:
-Surrounded by periosteum
-Blood vessels and nerves
throughout
-Osteocytes in lacunae
-Rigid extracellular matrix (due to inorganic calcium salts)
-Extracellular matrix (organic part) made by osteoblasts
-Appositional growth only
Functions of Bones
- Support
* For body and soft organs - Protection
* Brain, spinal cord, and vital organs - Movement
* Levers for muscle action - Mineral and growth factor storage
* Calcium and phosphorus, and growth factors reservoirs - Blood cell formation
* Hematopoiesis in red marrow - Triglyceride storage
* Fat, used for an energy source, is stored in bone cavities - Hormone production
* Osteocalcin
Axial Skeleton
-forms the long axis of the body
-includes the bones of the skull, vertebral column, and rib cage
-Support head, neck, and trunk
* Protect brain, spinal cord, and
thoracic organs
Appendicular Skeleton
-consists of the bones of the upper and lower limbs and the girdles (shoulder bones and hip bones) that attach the limbs to the axial skeleton
-helps us move (locomotion) and manipulate our environment
Long Bones
-longer than they are wide
-a shaft plus 2 ends
-all limb bones including fingers and toes except patella (kneecap) and wrist and ankle bones
Short bones
-cube shaped
- wrist and ankle bones
-seasamoid bones are formed in tendons (varies in size and number for individuals)
-some sesamoid alter the direction or pull of a tendon, others reduce friction and modify pressure on tendons to reduce abrasion or tearing
flat bones
-thin, flattened and usually a bit curved
-the sternum (breastbone), scapulae (shoulder blades), ribs and most cranial bones of the skull
Irregular bones
-complicated shapes that don’t fit the other classes
-includes vertebrae and hip bones
Why are bones organs?
-they contain different types of tissue (osseous tissue which dominates, nervous tissue in their nerves, cartilage, dense connective tissue covering their external surface, muscle and epithelial tissues in their blood vessels
Hand
includes bones of the carpus (wrist), bones of the metacarpus (palm) and phalanges (bones of the fingers)
Carpus (wrist)
-generally the area we call our hand/palm, not where the ulna (right lateral of where we associate wrist) or radius (left lateral of where we associate wrist)
-consists of 8 short bones/carpals in 2 irregular rows of 4 bones each
-on proximal row (to the ulna and radius) from lateral to medial (FROM THUMB) = scaphoid, lunate, triquetrum and pisiform
-all except pisiform form the wrist joint
-distal row carpals from lateral to medial (from thumb to other side) = trapezium, trapezoid, capitate and humane
- “Sally left the part to take Cindy home”
carpal tunnel syndrome
-the arrangement of carpus bones forms a concave anteriorly with ligament roofs over it creating a carpal tunnel
-Median nerve and tendons travel through carpal tunnel
* Overuse and inflammation of
tendons, which can compress median nerve, causing tingling and
numbness and movements of the thumb weakened
-pain is greatest at night
Metacarpus (palm)
-5 metacarpal long bones radiate from the wrist (carpus) and are numbered from 1 to 5 starting with the thumb
-bases of metacarpals interact with carpals proximally and with each other laterally and medially
-heads of metacarpals (knuckles) interact proximally with phalanges
-metacarpal 1 = thumb and is the shortest and most mobile and is more anterior than the others
-joint between metacarpal 1 and trapezium is unique as it allows opposition (touching thumb to fingertips of other fingers)
Phalanges (fingers)
-fingers are numbered 1 to 5 beginning with thumb (pollex)
-in most people, third finger is the longest
-each hand contains 14 mini long bones (phalanges) with 3 (distal, middle, proximal) on each finger except thumb (no middle)
Vertebral Column
-also called spine/spinal column
-consists of 26 irregular bones
-extends from the skull to the pelvis where it transmits the weight of the trunk to the lower limbs
-surrounds and protects spinal cord and provides attachment points for ribs and for muscles at back of neck
-fetus and infant = vertebral column with 33 vertebrae (separate bones)
-inferiorly, 9 will fuse to form the sacrum and coccyx and the rest remain and separate by intervertebral discs
Friction Ridge
-enhance our ability to grip certain surfaces and contribute to our sense of touch by enhancing vibrations detected by receptors in the dermis
-genetically determined and unique to each of us
-fingerprints = sweat pores that open along the crest leaving our identification on everything we touch
-only on thick skin
Reticular Dermis
-makes up about 80% of dermal thickness
-composed of coarse, dense irregular connective tissue
-dermal vascular plexus = blood vessels that nourish this layer and lies between this layer and subcutaneous tissue/hypodermis
-ECM contains interlacing collagen fibers
-
Cleavage (tension) lines
- formed by collagen fibers running parallel to the skin surface and the separations or less dense regions between them
-run longitudinally in the skin of limbs, and in circular patterns around the neck and trunk - externally invisible and important for surgeons because incisions made parallel to these lines heal more readily
Flexure Lines
-dermal folds that occur at or near joints, where the dermis is tightly secured to deeper structures (e.g., in palms)
-Since the skin cannot slide easily to accommodate joint movement in such regions, the dermis
folds and deep skin creases form
- also visible on the wrists, fingers, soles, and toes.
Skin Traumas
- Stretch marks: Extreme stretching of the skin, such as during pregnancy, can
tear the dermis, leaving silvery white scars called striae - Blisters: Short-term traumas like from a burn - Fluid filled pocket separating between epidermal and
dermal layers
3 pigments that contribute to skin color
- melanin: Only pigment made in skin
- Made from AA tyrosine
- Packaged into
melanosomes that are sent
to shield DNA of
keratinocytes from
damaging UV sunlight - Local accumulations form
freckles and pigmented
moles
-all humans have same number of melanocytes yet difference in skin color is due to kind and amount of melanin made (black people have melanocytes with darker melanosomes and keratinocytes retain it longer
-exposure to sunlight = tanning due to melanin buildup to protect the DNA of keratinocytes
-prolonged exposure = skin damage (elastic fibers clump causing leathery skin, skin cancer from depressed immune system and altered DNA)
Carotene
* Yellow to orange pigment
* Most obvious in palms and soles
* Accumulates in stratum corneum
and hypodermis
* Can be converted to vitamin A for
vision and epidermal health
Carotene
* Pinkish hue of fair skin due to
lower levels of melanin
Hemoglobin
* Three pigments contribute to skin color
Indications of disease
-cyanosis (skin turning bluish-grey especially in nail beds and mucous membranes because hemoglobin is poorly oxygenated
- fifth disease: reddened skin may indicate embarrassment , fever, inflammation, or allergy
- bruises/eccymoses: blood vessels are damaged and leak blood into surrounding tissue and as body breaks down the blood, the color of bruise changes
- brown or black necklace or bruises: dark areas around neck and in axillae are a sign of insulin resistance and elevated blood glucose
- yellowness: when liver not able to eliminate bilirubin, yellow pigment accumulates in body tissue (jaundice) and in sclerae
can be caused by eating large amounts of yellow veggies also due to carotene but not seen in eyes
Function of Hair
- sense insects on the skin before they bite or
sting us.
-Hair on the scalp guards the head against physical trauma, heat loss, and sunlight.
- Eyelashes shield the eyes, and nose hairs filter large particles like lint and insects from the air we inhale
Structure of a hair (come back)
- Hairs, or pili (pi’l i), are flexible strands produced by hair follicles and consist largely of dead, keratinized cells.
cranial bones
-Frontal (1)
Forms forehead, superior part of orbits (eye holes), and most of the anterior cranial fossa (A shallow depression in the bone surface); contains sinuses
Parietal (2)
Form most of the superior and lateral aspects of the skull
Occipital (1)
Forms posterior aspect
and most of the base
of the skull
Temporal (2)
Form inferolateral aspects of the skull and contribute to the middle cranial fossa;
have squamous, tympanic, and petrous parts
Sphenoid (1)
Keystone of the cranium; contributes to the middle cranial fossa and orbits; main parts are the body,
greater wings, lesser
wings, and pterygoid
processes
Ethmoid (1)
Small contribution to the anterior cranial fossa; forms part of the nasal septum and the lateral walls and roof of the nasal cavity; contributes to the
medial wall of the orbit
Facial bones
Nasal (2)
Form the bridge of the
nose
- Lacrimal (2)
Form part of the medial
orbit wall - Zygomatic (2)
Form the cheek and
part of the orbit - Inferior nasal concha (2)
Form part of the lateral
walls of the nasal cavity - Mandible (1)
The lower jaw
Maxilla (2)
Keystone bones of the
face; form the upper
jaw and parts of the
hard palate, orbits, and
nasal cavity walls
- Palatine (2)
Form posterior part of
the hard palate and
a small part of nasal
cavity and orbit walls - Vomer (1)
Inferior part of the nasal
septum
Vertebral column
Superior to inferior:
-Cervical curvature (concave)
7 vertebrae, C1 - C7
-Thoracic curvature
(convex)
12 vertebrae, T1 - T12
- Lumbar curvature
(concave)
5 vertebrae, L1 - L5
-Sacral curvature
(convex)
5 fused vertebrae
sacrum
-Coccyx
4 fused vertebrae
Upper Limb
Pectoral girdle:
-clavicle
Clavicle is in superoanterior thorax; articulates medially with sternum and laterally with scapula
-scapula
Scapula is in posterior
thorax; forms part of the
shoulder; articulates with
humerus and clavicle
upper limb (arm):
-humerus
Humerus is sole bone of
arm; between scapula and elbow
-ulna (forearm)
Ulna is the medial bone
of forearm between
elbow and wrist; with
the humerus (and radius)
forms elbow joint
-radius (forearm)
Radius is the lateral bone
of forearm; articulates
with carpals to form part
of the wrist joint
-carpals (hand onwards)
Carpals form a bony
crescent at the wrist ;
arranged in two rows of
four bones each
-metacarpals
Metacarpals form the palm; one in line with each digit
-phalanges
Phalanges form the fingers;
three in digits 11-V; two in
digit I (the thumb)
Projections That Are Sites of Muscle and Ligament Attachment (pg 211)
Tuberosity: Large rounded projection; may be roughened
Crest: Narrow ridge of bone; usually prominent
Trochanter: Very large, blunt, irregularly shaped
process (the only examples are on the femur)
Line: Narrow ridge of bone; less prominent
than a crest
Tubercle Small rounded projection or process
Epicondyle Raised area on or above a condyle
Spine Sharp, slender, often pointed projection
Burn is critical when…
Over 25% of the body has second-degree burns
- Over I0% of the body has third-degree burns
- There are third-degree burns of the face, hands, or feet (facial burns introduce the possibility of burned respiratory passageways, which can swell and cause suffocation)
Rule of nines
Anterior and posterior
head and neck, 9%
Anterior and posterior
upper limbs, 18%
Anterior and posterior
trunk, 36%
Perineum, 1%
Anterior and posterior
lower limbs, 36%
ECCRINE SWEAT GLANDS:
ECCRINE SWEAT GLANDS:
functions - temperature control some antibacterial properties
Type of Secretion
Hypotonic filtrate of blood plasma
Secretion Exits Duct At Skin surface
Body Location Everywhere, but especially palms,
soles, forehead
APOCRINE SWEAT GLANDS
May act as sexual scent glands
Filtrate of blood plasma with added proteins and fatty substances
Usually upper part of hair follicle; rarely, skin surface
Mostly axillary and anogenital regions
SEBACEOUS Sweat GLANDS
lubricate skin and hair
Help prevent water loss
- Antibacterial properties
Sebum (an oily secretion)
Usually upper part of hair follicle; sometimes, skin surface
Everywhere except palms and soles
