week 5 (skin and body movements, body flora, cartilage and skeletal system) Flashcards
integumentary system
The integumentary system helps maintain a constant body
temperature, protects the body, and provides sensory information
about the surrounding environment
Functions of the Integumentary System 1. Regulates body temperature. 2. Stores blood. 3. Protects body from external environment. 4. Detects cutaneous sensations. 5. Excretes and absorbs substances. 6. Synthesizes vitamin D.
what is the tissue of the epidermal layer like
the epidermis is the most superficial layer of the skin (what you touch)
it consists of keratinized straified squamous epithelium which means theres many layers of cells
generally the cells in the deepest layer are cubiodal and are continually dividing to produce cells that move to become part of the layer of cells above them
the most superficial celllayer consists of dead cells full of kertain
epidermis is avasular
stratum gerinativum (strutum basale)
The deepest layer of the epidermis is the stratum basale, composed of a single row of cuboidal or columnar keratinocytes. Some cells in this layer
are stem cells that undergo cell division to continually produce new kertaincytes
A distinctive feature of cells in this layer is the presence
of darkly staining granules of a protein called keratohyalin (ker′-
a-toˉ-HI
-
-a-lin), which assembles keratin intermediate filaments into
keratin. Also present in the keratinocytes are membrane-enclosed
lamellar granules (la-MEL-ar), which fuse with the plasma membrane
and release a lipid-rich secretion. This secretion is deposited in the
spaces between cells of the stratum granulosum, stratum lucidum, and
stratum corneum. The lipid-rich secretion acts as a water-repellent
sealant, retarding loss and entry of water and entry of foreign materials
stratum corneum
The stratum corneum consists on average of 25 to 30 layers of flattened
dead keratinocytes, but can range in thickness from a few cells in thin
skin to 50 or more cell layers in thick skin.
They are the final
product of the dif erentiation process of the keratinocytes. The cells
within each layer overlap one another like the scales on the skin of a
snake.
Its multiple layers of dead cells help the stratum corneum to protect
deeper layers from injury and microbial invasion
stratum lucidum
The stratum lucidum is present only in the thick skin of areas such as the
fingertips, palms, and soles.
It consists of four to six layers of flattened
clear, dead keratinocytes that contain large amounts of keratin and
thickened plasma membranes.
This probably provides an additional
level of toughness in this region of thick skin
stratum spinosum
Superficial to the stratum basale is the
stratum spinosum. This stratum
mainly consists of numerous keratinocytes arranged in 8–10 layers
This arrangement provides both strength and flexibility to the skin because of the bundle of kertain interfilaments and demosomes
kertainocytes
keratinocytes, which are arranged
in four or five layers and produce the protein keratin.
keratin is a tough, fibrous protein that helps protect the skin and underlying tissues from abrasions,
heat, microbes, and chemical
melanocytes
which develop from the ectoderm of a developing embryo and produce the pigment melanin
suboriferous gland
Throughout skin of most
regions of body, especially
skin of forehead, palms,
and soles.
Mostly in deep dermis
(sometimes in upper
subcutaneous layer).
secretion: Perspiration, which consists of water, ions (Na+ , Cl− ), urea, uric acid, ammonia, amino acids, glucose, and lactic acid
Regulation of body
temperature, waste removal,
stimulated during emotional
stress.
sebaceous gland (oil)
Prevent hairs from drying
out, prevent water loss from
skin, keep skin soft, inhibit
growth of some bacteria.
Largely in lips, glans penis, labia minora, and tarsal glands; small in trunk and limbs; absent in palms and soles.
Secretion Sebum
hair follicle
A hair follicle is a tunnel-shaped structure in the epidermis (outer layer) of the skin. Hair starts growing at the bottom of a hair follicle
stratum granulsom
At about the middle of the epidermis,
the stratum granulosum
consists of three to five layers of flattened keratinocytes that are
undergoing apoptosis.
apoptosis
apoptosis is an
orderly, genetically programmed cell death in which the nucleus
fragments before the cells die
dermis
connective tissue layer just below the epidermis
second major layer of skin, consists of two areas in the connective tissue
the layer adjacent to the basement membrane of the spidermal layer is called the papillary region. it consists of areolar connective tissue with a lot of elastic fibres
the reticular region is the deeper connective tissue layer which consisits of dense, irregular connective tissue (lots of collagen and elastic fibres)
fibroblasts
large, flat cells with
branching processes. They are present in all the general connective
tissues, and usually are the most numerous.
secrete fibers and
ground substance
elastic fibres
which are smaller in diameter than collagen fibers,
branch and join together to form a fibrous network within a connective
tissue. An elastic fiber consists of molecules of the protein elastin surrounded by a glycoprotein named fibrillin, which adds strength and
stability. Because of their unique molecular structure, elastic fibers are
strong but can be stretched up to 150% of their relaxed length without
breaking.
collagen fibres
are very strong and resist pulling or stretching, but they are not stif , which allows tissue
flexibility. The properties of dif erent types of collagen fibers vary
from tissue to tissue. For example, the collagen fibers found in cartilage and bone form dif erent associations with surrounding molecules
reticular region
Deeper portion of dermis consists
of dense irregular connective tissue with bundles ofthick collagen and some coarse elastic fibers.
Spaces between fibers contain some adipose cells, hair follicles, nerves, sebaceous glands, and sudoriferous
glands.
blood vessel (arteriole)
small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries
blood vessel (venule)
venule is a small blood vessel in the microcirculation that allows deoxygenated blood to return from capillary beds to larger blood vessels called veins. Venules range from 8 to 100μm in diameter and are formed when capillaries come together. Many venules unite to form a vein
sensory receptors
sensory receptors can be found throughout the skin. they will receive stimulis from internal and external environment
subcutaneous layer
this layer consists of areolar and adipose tissues. Fibers that extend from the dermis anchor the skin to the subcutaneous layer, which in turn attaches to underlying fascia, the connective tissue around muscles and
bones. The subcutaneous layer serves as a storage depot for fat and contains large blood vessels that supply the skin
amino acids in relation to the skin
Amino acids are important nutrients required for wound healing promotion and repair of the damaged skin
glucose in relation to the skin
cause hormonal changes and other biologic dysfunction that lead to acne. Optimizing our metabolic fitness with a glucose monitoring program like Levels can help us make choices to minimize our body’s exposure to excess glucose (sugar), which may help prevent premature skin aging and acne
oxygen in relation to the skin
Oxygenation has to do with breathing and blood flow. On and in the skin, as for other tissues in the body, oxygen is essential to the health and maintenance of the cells
feedback loop for body temp
by
liberating sweat at its surface and by adjusting the flow of blood in the
dermis. In response to high environmental temperature or heat produced
by exercise, sweat production from eccrine sweat glands increases; the
evaporation of sweat from the skin surface helps lower body temperature. In addition, blood vessels in the dermis of the skin dilate (become
wider); consequently, more blood flows through the dermis, which
increases the amount of heat loss from the body. In
response to low environmental temperature, production of sweat from
eccrine sweat glands is decreased, which helps conserve heat. Also, the
blood vessels in the dermis of the skin constrict (become narrow), which
decreases blood flow through the skin and reduces heat loss from the
body. And, skeletal muscle contractions generate body heat.
membrane
selective barrier; it allows some things to pass through but stops others
membrane
selective barrier; it allows some things to pass through but stops others
serous membrane
A serous membrane or serosa lines a body cavity that does not open directly to the exterior and it covers the organs that are within the cavity. Serous membranes consist of areolar connective tissue covered by mesothelium
A mucous membrane or mucosa lines a body cavity that opens directly to the exterior. Mucous membranes line the entire digestive, respiratory, and reproductive tracts, and much of the urinary tract. They consist of a lining layer of epithelium and an underlying layer of connective tissue
The cutaneous membrane or skin covers the entire surface of the body and consists
of a superficial portion called the epidermis and a deeper portion
called the dermis. The epidermis consists of keratinized stratified squamous epithelium, which protects underlying tissues
synovial membranes
Synovial membranes line the cavities of freely movable joints (joint cavities). Like serous membranes,
synovial membranes line structures that do not open to the exterior.
Unlike mucous, serous, and cutaneous membranes, they lack an
epithelium and are therefore not epithelial membranes. Synovial
membranes are composed of a discontinuous layer of cells called
synoviocytes, which are closer to the synovial cavity
(space between the bones), and a layer of connective tissue
mucous membrane
a body cavity that opens directly to the exterior. Mucous membranes line the entire digestive, respiratory, and reproductive tracts, and much of the urinary tract. They consist of a lining layer of epithelium and an underlying layer of connective tissue
cutaenous membrane
The cutaneous membrane or skin covers the entire surface of the body and consists
of a superficial portion called the epidermis and a deeper portion
called the dermis. The epidermis consists of keratinized stratified squamous epithelium, which protects underlying tissues
cartilage
consists of a dense network of
collagen fibers and elastic fibers firmly embedded in chondroitin
sulfate, a gel-like component of the ground substance. Cartilage can
endure considerably more stress than loose and dense connective
tissues. The strength of cartilage is due to its collagen fibers, and its
resilience (ability to assume its original shape af er deformation) is
due to chondroitin sulfate.
connective tissue vs cartilage
cartilage does not have nerves or blood in its extracellular matrix
chondrocytes
Chondrocytes are the cells responsible for cartilage formation, and they are crucial for the process of endochondral ossification, which is useful for bone development.
lacuane
a cavity or depression, especially in bone
perichondrium
s a layer of dense irregular connective tissue that surrounds the cartilage of developing bone. It consists of two separate layers: an outer fibrous layer and inner chondrogenic layer.
body flora
flora is the term used to describe the microorganisms that exist on or within the human body, such as the gut flora or the skin flora
host/parasite realtionship
demostarted when the bacteria causes a mild to sereve infection. the bacterical species gains a foothold in the body, repilcates and initates a defensive response by the host.
bacterica causes the disease which is called a pathogen
OR
bacteria that have gained a foothold on a membrane surface nut do not intatie defensibe response are normal body flora.
lactobacilli (protection)
live on the mucous membrane lining in the vagina. their presence maintains an acid pH i the vagina during reproductive year. This high pH has an affect on pathogens
staphyococci and streotococci (protection)
present on the skin and the mucous membranes area adherent to these surfaces. They suppress the adherence of other more pathogenic species since they completely carpet the surface
escherichia coli
present in the large intenstine and produces excess viatmin K. essential source of vitamin k for us.
probiotics
dietary supplements which contain potentially benefitcal bacteria or yeast. these bacterias cultures are given to ensure the re-established/ and or maintaenance of normal body flora
darkness in relation to bacteria growth
absence of light promotes bacterial growth. sunlight kills most bacteria within hours
the UVradiation light will damage the genetic material
temp in relation to bacteria growth
for each specices there is an optimum temperture - dependent on bacterial habitat. above or below inhibits growth
pH in relation to bacteria growth
optimum pH range for most bacteria is 6-8
outside the optimum range, hydrogen ions interfere with the metabolic processes.
prebiotics
dietary supplements which contain food items which will stimulate growth or actviity of normal body flora
hyaline cartilage
Hyaline cartilage contains a resilient gel as ground substance and appears in the body as a bluish-white, shiny
substance (fine collagen fibers are not visible with ordinary staining
techniques) prominent chondrocytes are found in lacunae surrounded by perichondrium (exceptions: articular cartilage in joints and
cartilage of epiphyseal plates, where bones lengthen during growth).
Most abundant cartilage in body; at ends of long bones, anterior ends of ribs, nose, parts of larynx, trachea, bronchi, bronchial tubes,
embryonic and fetal skeleton.
Provides smooth surfaces for movement at joints, flexibility, and support; weakest type of cartilage and can be fractured.
fribrocartilage
Fibrocartilage has chondrocytes among clearly visible thick bundles of collagen fibers within extracellular matrix; lacks perichondrium.
Pubic symphysis (where hip bones join anteriorly), intervertebral discs, menisci (cartilage pads) of knee, portions of tendons that insert into cartilage.
Support and joining structures together. Strength and rigidity make it the strongest type of cartilage.
elastic cartilage
Elastic cartilage has chondrocytes in threadlike network of elastic fibers within extracellular matrix; perichondrium present.
Lid on top of larynx (epiglottis), part of external ear (auricle), auditory (eustachian) tubes.
Provides strength and elasticity; maintains shape of certain structures.
skeletal system
It gives the body its shape, allows movement, makes blood cells, provides protection for organs and stores minerals
two type of connective tissue that make up the skeletal system
Two major forms of supportive connective tissue, cartilage and bone, allow the body to maintain its posture and protect internal organs
diaphysis
is the bone’s shaf
or body—the long, cylindrical, main portion of the bone
epiphysis
are the proximal and distal ends of the bone
articular cartilage
a thin layer of hyaline cartilage covering
the part of the epiphysis where the bone forms an articulation (joint)
with another bone. Articular cartilage reduces friction and absorbs
shock at freely movable joints. Because articular cartilage lacks a
perichondrium and lacks blood vessels, repair of damage is limited
metaphyses
are the regions between the diaphysis and the epiphyses. In a growing bone, each metaphysis contains an epiphyseal (growth) plate, a layer of hyaline cartilage that allows the diaphysis of the bone to grow in length
When a bone ceases to grow in length at about ages 14–24, the cartilage in the epiphyseal plate is replaced by
bone; the resulting bony structure is known as the epiphyseal line.
periosteum
is a tough connective tissue sheath and its associated blood supply that surrounds the bone surface wherever it is not covered by articular cartilage
Some of the
cells enable bone to grow in thickness, but not in length. The periosteum also protects the bone, assists in fracture repair, helps nourish bone tissue, and serves as an attachment point for ligaments and tendons.
The periosteum is attached to the underlying bone by perforating fibers or Sharpey’s fibers, thick bundles of collagen that extend from the periosteum into the bone extracellular matrix
endosteum
A membrane lining the inner surface of the bony wall also identified as the lining membrane of the Bone marrow cavity is endosteum; The endosteum lines the Haversian canal and all the internal cavities of the bone.
medullary cavity
or
marrow cavity, is a hollow, cylindrical space within the diaphysis that
contains fatty yellow bone marrow and numerous blood vessels in
adults. This cavity minimizes the weight of the bone by reducing the
dense bony material where it is least needed. The long bones’ tubular design provides maximum strength with minimum weight.
red marrow
Within certain bones, a connective tissue called red bone marrow produces red blood cells, white blood
cells, and platelets, a process called hemopoiesis.
Red bone marrow consists of developing blood cells, adipocytes, fibroblasts, and macrophages
within a network of reticular fibers
yellow marrow
consists mainly of adipose cells, which store triglycerides. The stored triglycerides are a
potential chemical energy reserve.
matirx
refers to the “stuff” in the cell
osteoprogenitor (osteogenic cell)
develops into a osteoblast
osteoblast
forms bone extraextracellular matrix
osteoclast
functions in the reorsptioin, the breakdown of bones
make spongy bone
spongy bone
also called trabecullar and cnacellous bone tissue
exclusisvely found interior to the compact bone
lamellae are arranged in long and irregualar shpaed columns called trabeculae
many spaces between trabeculae are filled with red or yellow bone marrow depending on bone type
compact bone
very few spcases
osteon/haversian systems - concentric rings of osteocytes and mineralized ECM surronding a central canal with blood vessels, etc.
flat bones
these bones are expanded into broad, flat plates, as the cranium(skull), the ilium(pelvis), stenrim and the rib cage
bones: occcupital parietal frontal nasal lacrimal vomer hip bone (coxal) sternum ribs scapulae
long bones
a bone that has a shaft and 2 ends and is longer than it is wide
bones in upper limbs: humerous radius ulua metacarpals phalanges
bones in lower: tibia fibula femur metatarsals phalanges
irregular bones
are bones which from their perculiar form, cannot be grouped as long, short, flat or sesamoid bones. protection of nervous system and multiple achor points for skeletal muscle attachment
boens: vetrebae sacrum coccyx temporal manible facial bones
short bones
Short bones include the carpal bones of the hands that allow movement of the wrist, and the tarsal bones of the feet that allow movement of the ankle. Short bones are shaped roughly as a cube and contain mostly spongy bone. The outside surface is comprised of a thin layer of compact bone.
bone: carpus
tarsus
seasmoid bone
A sesamoid bone is a small round bone that is imbedded within a tendon, whose purpose is to reinforce and decrease stress on that tendon
kneecap
joint
a joint is the point at which two bones articulate. for two types of joint there is NO space and cavity between the two bones.
if the space between the two bones are filled with cartilage the joint is known as a catilgagenous joint. one example would be the costa cartilage between the first rib and the sternum
if the space between the two bones filled with dense fibrous connective tissue, it is called a fibrous joint an example of this would be the fibrous joint between flat bones of the skull
vertebral body
Vertebral body is the thick oval segment of bone forming the front of the vertebra also called the centrum. The cavity of the vertebral body consists of cancellous bone tissue and is encircled by a protective layer of compact bone.
vertebral arch
A circle of bone around the canal through which the spinal cord passes. A vertebral arch is composed of a floor at the back of the vertebra, walls (the pedicles), and a roof where two laminae join
The vertebral arch surrounds and protects the spinal cord
vertebral foramen
In a typical vertebra, the vertebral foramen is the foramen (opening) formed by the anterior segment (the body), and the posterior part, the vertebral arc
Within this foramen the spinal cord and associated meninges are housed
intervertebral discs
The intervertebral disc (IVD) is important in the normal functioning of the spine. It is a cushion of fibrocartilage and the principal joint between two vertebrae in the spinal column.
They also provide a shock-absorbing effect within the spine and prevent the vertebrae from grinding together.
ossification
Bone formation, also called ossification, process by which new bone is produced. Ossification begins about the third month of fetal life in humans and is completed by late adolescence
intramembranous ossification
- menschyme is the connective tissue of the embryo that froms the flat bones and the clavicle (menschyme is a loose misture of cells filled in with collagen fibre in the ECM)
- menchumal cells reieve a signal to differentiate into osteogenic cells, and then forming a cluster of osteoblasts that becomes the ossification centre
- cells from the ossification centre start secreting ECM - this is known as osteoid- mainly collagen fibres and some chondroition sulfate
- cells are now surronded by their secretions and become osteocytes
- canaliculi are formed
- calcium and mineral salts are now released and the ECM begins to harden
- bone ECM begins to form ande develops into trabeculae that fuse together to form spongy bone
- blood vessels get trapped in the newly forming tissue
- connective tissue assoiated with the blood vessels turns into bone marrow
- the menchyme at the periphery of the bone begin to condense and form an intiially fibrous periosteum
- a thin layer of compact bone begins to replace the surface layers of the spongy bone based on the osteoblasts at the inner sirface of the new periosteum
endochondral ossification
- hyaline cartilage is formed (mesenchymal cells crowd and differentiate into chrondroblasts)
- chondroblasts secrete ECM that is eventually covered by a membrane called the perichondrium
- growth of cartilage continues and buried chondroblasts become chondrocytes, which then. divide repeatly (also called intersitial growth)
- new chrondroblasts also emerge from the perichondrium and deposit more ECM on the surface increasing thickness
- chonrocytes in the middle region of the mass enlargen and their surronding material starts to calcify
- cells withini this region are now in tough material, no longer receiving nutrient supply (no blood vessels in model), and die, leacing an empty space which eventually become lacuane
- nutrient artery penetrates the perichondrium through nutrient foramen in the middle of the cartilage model
- osteogenic cells in the perichondrium become activiated by this and turn into soteoblasts (perichrium now called periosteum)
- near middle of model, periosteal arties grow into disintegreting calcified cartilage inducing grwoth of primary ossification centre
- osteoblasts deposit bone over the remnants of calcified cartilage, first forming trabeculae of spongy or cacellous bone - this will spread toards both ends of the model
- as growth of the primary ossification centre continues to expand to the ends of the model, osteoclasts break down some of the newly formed trabeculae, creating a cavity
- epiphyseal arties enter into the epiphyses, allowing for the fromation of secondary ossification centres
- chondrocytes die and are replacede by osteoblasts that form trabeculae and spongy bone
- the hyaline cartilage remaining at the edges become articular cartilage
- small amounts of hyaline cartilage remain in the metaphysis where the nutrient and epiphsyeal arties fail to reach
- thie becomes the epiphyseal playe, and will remian cartilage until you are about 20, then replaced with compact bone
bone resorption
the removal of minerals and collagen fibers from bone by osteoclasts
bone deposition
the addition of minerals and collagen fibers to bone by osteoblasts
human growth hormone
HGH, produced by the pituitary gland, spurs growth in children and adolescents. It also helps to regulate body composition, body fluids, muscle and bone growth, sugar and fat metabolism, and possibly heart function
thyroid hormone
thyroid is located in front of the neck and is responsible for the production of thyroid hormones. The thyroid gland releases triiodothyronine (T3) and thyroxine (T4). These hormones play an important role in regulation of your weight, energy levels, internal temperature, skin, hair, nail growth, and more
estrogen
Estrogens are a group of hormones that play an important role in the normal sexual and reproductive development in women. They are also sex hormones. The woman’s ovaries make most estrogen hormones, although the adrenal glands and fat cells also make small amounts of the hormones
testosterone
Testosterone is the male sex hormone that is made in the testicles. Testosterone hormone levels are important to normal male sexual development and functions. During puberty (in the teen years), testosterone helps boys develop male features like body and facial hair, deeper voice, and muscle strength
parathryoid hormone vs calcitonin
Parathyroid hormone works in concert with another hormone, calcitonin, that is produced by the thyroid to maintain blood calcium levels. Parathyroid hormone acts to increase blood calcium levels, while calcitonin acts to decrease blood calcium levels
perforating (volkmann’s) canals
Volkmann’s canals are any of the small channels in the bone that transmit blood vessels from the periosteum into the bone and that communicate with the haversian canals
they are the horizontal while the haversian canals will be going up and down
central (haversain) canals
Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix.
The osteonic canals contain blood vessels that are parallel to the long axis of the bone
lacunae
a cavity or depression, especially in bone
canaliculi
canaliculus is a small canal or duct or passageway in the body
Bone canaliculus. It is a small channel in ossified bone, particularly between the lacunae of ossified bone
lamallae
lamellae refers to a thin layer, membrane or plate of tissue
concentric lamallae
The concentric lamellae are like tubes of different size fitting inside each other to make an osteon
tree rings
intersitial lamallae
the interstitial lamellae fill the spaces between osteons
circumferential lamellae
the circumferential lamellae run around the circumference of the bone
ostoens
Osteons are formations characteristic of mature bone and take shape during the process of bone remodeling, or renewal
trabeculae
trabecula is a small, often microscopic, tissue element in the form of a small beam, strut or rod that supports or anchors a framework of parts within a body or organ
sterilization
destruction of all microbes (including viruses and endospores) from an object
Aseptic
An environment or procedure that is free of contamination.
Disinfection
Use of physical or chemical agents (disinfectants) to destroy
microorganisms on inanimate objects
Antisepsis
disinfection of living tissue (skin) with antiseptics
Degerming
The removal of microbes from a surface by scrubbing. Soap and
alcohol are common degerming agents
