MOD 3-4 Flashcards
A group of cells with similar structure and function, along with extracellular substances located
between cells.
Tissue
the microscopic study of tissue structure.
histology
what are the 4 basic types of tissues?
epithelium, connective, muscular, nervous
This type of tissue covers and protects surfaces, both outside and inside the body.
epithelium tissue
a diverse primary tissue type that makes up part of every organ in the body.
connective
Type of tissue that makes movement possible by contracting or shortening.
muscle
This type of tissue is responsible for coordinating and controlling many body activities
nervous
what are the cell surfaces?
free/apical surface, lateral surface, basal surface
general characteristics of epithelial tissue
composed of cell with very little extra cellular matrix, covers body surfaces,
major functions of epithelia
protecting underlying structures, acting as a barrier, permitting the passage of substances, secreting substances, absorbing substances
classification of epithelium
simple, stratified, pseudostratified, transitional
single layer of cells
simple
more than one layer of cells
stratified
special type of simple epithelium; appears to be stratified but is not
pseudostratified
modification of stratified epithelium that can be greatly stretched
transitional
what are the types of epithelium
squamous, cubodial, columnar
these are cells that are flat or scale-like
squamous
cells are cube shaped; about as wide as they are tall
cubodial
cells tend to be taller than they are wide
columnar
increase cell’s surface area
microvilli
move materials across cell’s surface
cilia
produces mucus
goblet cells
structures that secrete substances onto a surface, into a cavity, or into blood; primarily composed of epithelium, with a supporting network of connective tissue.
glands
two types of glands
endocrine and exocrine
glands with ducts
exocrine
glands with no ducts (directly into the bloodstream)
endocrine
distinguished by its extracellular matrix which results from the activity of specialized connective tissue cells,
connective tissues
major components of extracellular matrix
protein fibers, reticular fibers, elastic fibers
functions of connective tissue
enclosing and separating other tissues, connecting tissue to one another, supporting and moving parts, storing compound, cushioning and insulating, transporting, protecting
consists of relatively few protein fibers that form a lacy network, with numerous spaces filed with ground substance & fluid.
Loose Connective Tissue -
has relatively large number of protein fibers that form thick bundles & fill nearly all of the extracellular space
Dense Connective Tissue -
is composed of chondrocytes; resilient, relatively rigid & enables to spring back after being compressed; not penetrated by blood vessels; therefore, heals slowly after an injury.
cartilage
hard connective tissue that consists of living cells & mineralized matrix;
composed of osteocytes which are located within lacunae; the matrix is organized into layers called lamellae.
bone
examples of connective tissue proper
loose connective tissue, dense connective tissue
examples of supporting connective tissue
cartilage, bone
examples of fluid connective tissue
blood, hemopoietic tissue,
composed of formed elements & fluid matrix
blood
composed of red and yellow marrow
hemopoietic tissue
main function is to contract, or shorten, making movernent possible; length is greater than its diameter
muscle tissue
specialized to conduct action potentials (electrical signals); located in the brain, spinal cord & ganglia
nervous tissue
transmit information in form of action potentials, store information, & integrate
& evaluate data
neurons (nerve cell)
major parts of neurons
cell body, dendrites, axon
site of general cell functions; contains nucleus
cell body
receive stimuli leading to electrical changes
dendrites
send action potential to another neuron
axon
surround the neurons; function to protect, nourish & form specialized sheaths around axons
glia
a thin sheet or layer of tissue that covers a structure or lines a cavity. The body is
composed of four membranes, one external and 3 internal.
tissue membrane
external tissue membrane; compose of stratified squamous epithelium & dense connective tissue.
cutaneous membrane/skin
occurs when tissues are damaged,can result from the immediate & painful events that follow trauma and mobilizes the body’s defenses & isolates and destroys microorganisms, foreign materials, and damaged cells.
inflammation
results when the agent responsible for an injury is not removed or something else DORA interferes with the healing process.
chronic inflammation
is an unpleasant but beneficial occurrence in the human body when tissues are damaged.
inflammatory response
are substances that are released or activated in the injured tissues and adjacent blood vessels.
chemical mediators
a type of phagocytic white blood cell that enters the tissues and fights infections by ingesting bacteria, It dies after ingesting a small number of bacteria
neutrophil
the mixture of dead neutrophils, other cells, & fluid that can accumulate
pus
is the substitution of viable cells for dead cells.
tissue repair
two types of tissue repair
regeneration & fibrosis/replacement
the new cells are the same type as those that were destroyed, and normal function is usually restored; no scar formation.
regeneration
primarily used in this type; self-renewing, undifferentiated cells that continue to divide throughout life.
stem cells
a new type of tissue develops that eventually causes scar production:
and the loss of some tissue function. (ex: brain, heart, skeletal muscles)
fibrosis/replacement
how does the tissue repair process work?
In the process that repairs tissue damage, a clot is first formed. Next, new epithelial cells grow into the wound, followed by the formation of granulation tissue. Finally, granulation tissue is replaced with new connective tissue.
contains the threadlike protein fibrin, Which binds the edges of the wound together and stops the bleeding.
clot
dried clot; seals the wound and helps prevent infection,
scab
a second type of phagocytic cells that removes the dead neutrophils, cellular debris, & the decomposing clot.
macrophage
produces collagen and other extracellular matrix components.
fibroblast
a delicate, granular-appearing connective tissue that consists of fibroblasts, collagen, and capillaries.
granulation tissue
a result of contraction of fibroblasts in granulation tissue; pulls the edges of wound closer together.
wound contracture
consists of the skin and its accessory structures (hair, nails, and glands); of the more familiar systems of the body because it covers the outside of the body and is easily observed
integumentary system
this means covering
integument
major functions of integumentary system
protection, sensation, vitamin d production, temperature regulation, excretion
what process will occurr to heat the body
Blood vessels constrict to reduce blood flow to skin and heat is retained.
what process will occur to heat the body?
Blood vessels constrict to reduce blood flow to skin and heat is retained.
what process will occur to cool down the body?
Blood vessels in dermis dilate and heat is transferred from deep in tissues to an skin and sweat is produced.
Skin glands can remove large amounts of sweat, but only a small amount of waste products (urea, uric acid, and ammonia). They do not play a significant role in the excretion of waste products
excretion
the most superficial layer of the skin; made up of stratified squamous epithelium.
epidermis
distinct layer of epidermis
strata
what are the five epidermal strata
stratum basale/germinativum, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum
deepest layer; consists of cuboidal or columnar cells that undergo mitotic divisions about every 19 days. This stratum is a single layer of cells and firmly attached to dermis.
stratum basale/ stratum germinativum
spiny in appearance due to the protruding cell processing that join the cells; composed of 8 to 10 layers of keratinocytes (cells that manufacture & store the protein keratin)
stratum spinosum
has grainy appearance due to further changes to the keratinocytes as they are pushed from the spinosum; generate large amounts of keratin, which is fibrous
stratum granulosum
a smooth, seemingly translucent layer that is found only on thick skin of palms, soles, & digits
stratum lucidum
outermost layer of epidermis; 20 to 30 layers of dead squamous cells filled with keratin & accounts for 75% of epidermal thickness; joined by desmosomes. This layer is also coated and surrounded by lipid, which acts as waterproofing material.
stratum corneum
excessive sloughing of corneum from the surface of the scalp,
dandruff
hard skin; forms when the skin has been exposed to frequent friction resulting in increased layers of corneum and thickened areas
callus
occurs when the corneum thickens to form a cone-shaped structure over a bony prominence.
corn
a process in which new cells (with keratin) is pushing old cells to the surface. It takes 40 to 56 days for the new cells to reach the surface,
keratinization
the 2nd major skin region; composed of dense collagenous connective tissue containing fibroblasts, adipocytes, macrophages, nerves, hair follicles, smooth muscles, glands, and lymphatic
vessels.
dermis
these are areas where skin is most resistant to stretching; caused by orientation of collagen fibers; vital in scarring.
cleavage lines/tension lines
visible lines through the epidermis that result, from overstretched skin, for any reason, damaging the dermis; usually common when a person increases in size quite rapidly.
stretch marks
layers of dermis
papillary layer, reticular layer
thin connective tissue layer that contains blood vessels.
papillary layer
deepest layer of dermis; accounts for 80% of dermis.
reticular layer
factors affecting skin color
pigments in skin, blood circulating through the skin, thickness of stratum corneum, genetics
irregularly shaped cells with many long processes that extend between the epithelial cells of the deep part of epidermis; responsible for production of melanin,
melanocytes
these are melanin-containing vesicles which move into the cell processes of melanocytes
melanosomes
the group of pigments primarily responsible for skin, hair, and eye color and provides protection against ultraviolet light from sunlight
melanin
determinants of melanin production
genetic factors, exposure to uv light, hormones
responsible for the amounts of melanin produced in different races.
genetic factors
a recessive genetic trait that causes a deficiency or an absence of melanin
albinism
stimulates melanocytes to increase melanin production to help protect the
skin resulting in a suntan.
exposure to uv light
It is the skin reacting to UV exposure.
sunburn
certain hormones, such as estrogen & melanocyte-stimulating hormone (MSH), increase the melanin production during pregnancy.
hormones
It is attaches the skin to underlying bone and muscle; below the dermis, not part of the skin; made up of loose connective tissue, including adipose tissue; contains about 1/4 of the body’s stored lipids
Subcutaneous Tissue / Hypodermis
is found everywhere on the skin, except on the palms, the soles, lips, nipples, parts of genitalia, and the distal segments of fingers and toes,
hair
what are the different hair components
hair shaft, hair root, hair bulb, hair follicle, hair cortex, hair medulla, hair papilla, arrector pili
flexible strands of keratinized cells; protrudes above the surface of the skin,
hair shaft
part of the hair that protrudes below the surface.
hair root
base of hair root; where the hair is produced
hair bulb
an invagination of the epidermis that extends deep into the dermis; a group of
cells that surround the root and bulb and responsible for giving different shapes to the hair.
hair follicle
a hard covering of hair that is surrounded by the cuticle, a single layer of overlapping cells that holds the hair in the hair follicle.
hair cortex
the softer center that is surrounded by the cortex
hair medulla
an extension of the dermis that protrudes into the hair bulb; the blood vessels within supply the hair bulb with the nourishment needed to produce hair.
hair papilla
made up of smooth muscle that surrounds each hair follicle; its contraction causes the hair to become more perpendicular to the skin’s surface called “goose bumps”
arrector pili
are simple, branched acinar glands; most are connected by a duct to the hair
follicle.
sebaceous glands
release sweat by merocrine secretion that is made mostly of water, with a few salts, located in almost every part of the skin but most numerous in palms and soles; open into the sweat pores
eccrine sweat glands
- produce a thick secretion rich in organic substances by merocrine
secretion, though some glands demonstrate holocrine secretion; located only in armpits and genitalia; open into the hair follicles and become active during puberty, causing body odor.
apocrine sweat glands
a thin plate with layers of dead stratum corneum cells with a very hard type of keratin.
nail
what are the parts of the nail? (nail structure)
nail body, nail root, cuticle/eponychium, nail matrix, nail bed, lunula
the visible part of the nail
nail body
the covered part by the skin.
nail root
a stratum corneum that extends onto the nail body.
cuticle/eponychium
made up of epithelial cells with a stratum, basale that gives rises to most of the nail continuation of nail roots and is thicker than nail bed.
nail matrix
located distally to the nail matrix & attaches to nail; made up of epithelial cells with a stratum basale
nail bed
a small part of the nail matrix that can be seen through the nail body as a whitish, crescent-shaped area at the base of the nail.
lunula
caused by increased blood flowing through the skin.
redness/blushing
bacterial infection that causes reddish rash on the skin.
scarlet fever
caused by decreased blood flow.
pallor/paleness
a bluish color of skin caused by a decrease in the blood oxygen content. Associated with impaired circulation or respiratory functions.
cyanosis
a yellowish discoloration of the skin. Associated with liver disorder, too much consumption of carotene
jaundice
a yellow pigment found in plants (squash & carrots); normally used as a source sist
of vitamin A and accumulates in lipids of stratum corneum & in the adipocytes of dermis and subcutaneous.
carotene
a darkened skin piamentation usually caused by stimulant effect of excess
adrenocorticotropic hormone (ACTH) on the melanocytes.
bronzing
a blue to purple discoloration caused by broken blood vessels.
bruising
is an injury to a tissue caused by heat, cold, friction, chemicals, electricity, or radiation.
burn
classifications of burns
partial-thickness burn, full-thickness burn
the part of the stratum basale remains viable, and regeneration of the anglist
epidermis occurs from within the burn area, as well as from the edges of the burn
partial thickness burn
a burn that only involves the epidermis
first-degree burn
a burn that involves both the epidermis and dermis
second-degree burn
the epidermis and dermis are completely destroyed, and a painless kind of burn because the sensory receptors have been destroyed
third-degree burn
Most common type of cancer and mainly caused by UV light exposure from the sun.
skin cancer
can cause tanning of the skin; associated with malignant melanomas.
UVA rays
can cause burning of the skin associated with basal cell & squamous cell carnicomas
UVB rays
most frequent type that affects the cells in stratum basale and extends
into dermis to produce an open wound; readily treatable with surgery.
Basal Cell Carcinoma
develops from cells immediately superficial to the stratum basale;
if untreated, can metastasize and lead to death.
squamous cell carcinoma
a rare form that arises from melanoeytes, usually in pre-existing mole appear as a large, flat, spreading lesion or as a deeply pigmented nodule, metastasis is common and often fatal.
malignant melanoma
