Chapter 3: Compartmentation: Cells and Tissues
pluripotent
Cells that are capable of developing into most, but not all, of the body's cell types
melanocytes
Contain the pigment melanin Scattered throughout stratum basale
______ contribute to mechanical strength of tissue
anchoring junctions (have been compared to zippers or buttons)
carbohydrates bound to lipids or proteins are exclusively found on which side of the membrane
externally
extracellular matrix
extracellular material that is synthesized and secreted by the cells of a tissue
lungs, blood vessels, and skin need what combination of fibers for elasticity?
fibrillin + elastin
filaments and sheets of elastic fibers
fibrillin + elastin coming together
the segment of the transmembrane that passes through the bilayer is (polar/nonpolar)
nonpolar
most common form of adipocyte in adult human is
white fat adipocytes
can a cell be both fixed and mobile
yes
do adults have brown fat? how was this proved?
yes, CT and PET scans
Osteocystes
bone cells
peripheral proteins attach to other membrane proteins through __________ interactions and can be removed how? examples?
*noncovalent interactions* and can be separated from membrane by chemical methods without destroying membrane ex: enzymes, structural binding proteins that anchor the cytoskelteron
epithelial are classified on the basis of
*number* of cell *layers* and *shape* of *cells* at the apical surface
tight junctions proteins? function?
*restrict/block movement of material between the cells they link* claudins and occludins help partly fuse membrane of adjacent cells together varying degrees of leakiness
clast suffix in connective tissue type cells means
cells that are actively breaking down matrix
chondrocytes
cells that synthesize the extracellular matrix of cartilage
if detected early ______ is one of the most treatable forms of cancer
cervical caner
cartilage matrix is formed by
chondrocytes produce firm but flexible matrix
Elastin
coiled, wavy protein that returns to its original length after being stretched (elastance)
protein that dominates in dense connective tissue is
collagen
matrix fibers include
collagen elastin fibrillin fibronection
secretory vesicles
contain protein that will be released by cell
tissues range in complexity, how
contain single type of tissues (lining of blood vessels) or multiple (connective tissue)
adipocyte of white fat
contains a single enormous lipid droplet that occupies most of the cell volume
other epithelial such as kidney and intestinal tract,
control the movement of materials between the external environment and the extracellular fluid
cilia in upper airways and part of female reproductive system do what
create current that sweep fluids or secretions across the cell surface
centrioles
cylindrical bundle of 27 microtubules, arranged in 9 triblets
Cells that are neither growing, secreting matrix components, nor breaking down matrix may be given the suffix
cyte
microvilli are supported by
cytoskeleton fibers
cytoplasm is made out of
cytosol, insoluble particles called inclusions, insoluble proteins fibers, and membrane bound structures (organelles).
examples of things epithelial secrete into blood are
hormones
where is the diaphragm
in between thoracic and abdominopelvic cavity, remember it forms the floor of thoracic cavity
suffix blast on connective tissue means
indicates a cell that is either growing or actively secreting extracellular matrix
SER
lacks attachment of ribosomes synthesis of fatty acids, steroids, and lipids occurs here also phospholipids cholesterol is modified into steroid hormones (ex: estrogen and testosterone)
cancer cells can usually be recognized by a ...
large nucleus surrounded by a relatively small amount of cytoplasm
liposomes structure
larger spheres with bilayer phospholipid walls. hollow center with an aqueous core
microtubules size composition protein function
largest of all three (25nm) tubulin (globular) cytoskeleton; movement of cilia, flagella, and chromosome (centrioles); intracellular transport of organelles
nuclear envelope
layer of two membranes that surrounds the nucleus of a cell contain pores
stem cells
less specialized cells that retain the ability to divide
adherens junctions
link actin fibers in adjacent cells together
gland
secretory epithelial cells clumped exocrine and endocrine
transporting epithelial
selective about what can cross them and are found primarily in the intestinal tract and the kidney - exchange of nongaseous materials (ions and nutrients) b/w internal and external environment
primary cilia in the kidney
sense fluid flow
exocrine glands produce two types of secretion:
serous secretions mucous secretions
cytoskeleton: intracellular transport
serves as railtrack to move organelles
how do histologists describe tissue
shape and size of cells arrangement of cells in tissue the way cells are connected to one another amount of extracellular material present in tissue
Cilia
short, hairlike structures projecting from the cell surface
basolateral membrane
side of epithelial cell facing the extracellular fluid can have folds that increase surface area
two types of epithelial layering
simple stratified
gap junction protein? function?
simplest *allow direct and rapid cell-to-cell communication* through cytoplasmic bridges between adjoining cells connexins interlock to create passageways are able to open and close for regulation allow both chemical and electrical signals to pass rapidly
goblet cells
single exocrine cells that produce mucus
sperm has ____ flagella
1
centrioles direct the movement of
DNA
proteoglycans
are glycoproteins
resistance from stretching and twisting in skin is promoted by
*strong* linkage of anchoring cell junctions
(T/F) Cilia is a continuation of the cell membrane
true
answer percent protein, lipid, and carbohydrate for red blood cell membrane myelin membrane around nerve cells inner mitochondrial membrane
*NOTE* how inner mitochondrial membrane has 0% carbs
two main fluid compartments in body
(1) Extracellular fluid (2) intracellular fluid
body is divided into three major body cavities: by.... lined....
(1) cranial cavity-- skull (2) thoracic cavity -- thorax (3) abdominopelvic cavity tissue and bones with tissue membranes
transporting epithelia: cell shape
*thicker* than cells of exchange epithelia, and they act as a barrier as well as an entry point *cuboidal or columnar* *simple epithelial*
how is it that lysosomes become acidic?
- 7.0-7.3 pH while leaving Golgi (for safety) - accumulates H+ while in cytoplasm and enzymes activate
cytoskeleton: Assembly of cells into tissues.
- Protein fibers of the cytoskeleton connect with protein fibers in the extracellular space, linking cells to one another and to supporting material outside the cells - allow transfer of info between cells
muscle tissue characteristics
- contract produce force and movement
mucus
- acts as a lubricant for food to swallow - trap for foreign particles and microorganisms inhaled or ingested - protective barrier between epithelium and enviornment
types of muscle tissue
- cardiac (heart) smooth (make up organs) skeletal (attach to bones)
which cells have a lot of cilia?
- cells lining upper airways - and part of the female reproductive tract
Tay Sachs disease
- imperfection in lysosomes - in kinds - can't break down glycolipids
neural and muscle tissue characteristics
- minimal extracellular matrix - limited to supportive layer called the external lamina - gap junctions
best known endocrine glands
- pancreas - thyroid - gonads - pituitary glands all of which are in kidney tubules, lining of digestive tract, in walls of heart
cytoskeleton: internal organization
- stabilize position of organelles
primary cilia
-- most cells of the body contain a single, stationary, or non-motile, cilium - lack central pair of microtubules - sensors of external environment, passing information into the cell
cranial cavity contains... thoracic cavity contains... abnominopelvic cavity contains....
--brain --heart & lungs --(abdomen)-- stomach, spleen, pancreas, intestines, liver, gallbladder......(pelvis) -- reproductive organs, urinary bladder, terminal portion of large intestine
fibronectin
-An extracellular glycoprotein secreted by animal cells -Helps attach cells to extracellular matrix through actin filaments and integrins (focal adhesions) - wound healing and blood clotting
(T/F) ground substance == matrix
1 = True
5 important functions of cytoskeleton
1 cell shape 2 internal organization 3 intracellular transport 4 assembly of cells into tissue 5 movement
two general types of epithelial tissues
1) lie on surface of body or line inside of tubes or hollow organs 2) secretory epithelia that synthesize and release substances into extracellular space
general functions of the cell membrane include
1) physical isolation 2) regulation of exchange with the environment 3) communication between the cell and its environment 4) structural support
functionally, the body has ____ fluid compartments
3
Many physiologically important membrane proteins have ____ transmembrane segments,. Others cross the membrane _____ and up to _____
7; 1; 12
relative thickness of cell membrane
8 nm
flagella composition longer or shorter than cilia? microtubules?
9 microtubules surrounding a central pair, they terminate inside the cell at basal body considerably longer than cilia
cilia composition
9 pairs of microtubules surrounding a central pair they terminate just inside the cell at basal body
*NOTE* (1/3) of all proteins are membrane proteins 10 to 50 different types of proteins inserted into membranes
:P
*NOTE* The lumens of some organs are outside the body
:P
*note* lipid anchored proteins were previously thought to be peripheral proteins, but are actually integral proteins
:P
TISSUES YAY :)
:P
ground substance varies depending on type of connective tissue, for example blood (watery) and bone (very hard)
:P
*FACT:* Heart muscle has gap junctions that allow chemical and electrical signals to pass rapidly from one cell to the next
:[
Golgi Apparatus
A system of membranes that modifies and packages proteins for export by the cell
Glycolipids play a key role in body's immune response example?
ABO blood groups are determined by the number and composition of sugars attached to membrane sphingolipids.
osteoclast
Bone-destroying cells
cell-cell anchoring junction in vertebras are accomplished through
CAMs called cadherins, which connect with one another across the intercellular space
cell-matrix anchoring junction in vertebras are accomplished through
CAMs called integrins
Integrins
CAMs that create cell-matrix anchoring junctions also bind to signal molecules in the cell's environment
chromatin
Clusters of DNA, RNA, and proteins in the nucleus of a cell
the ruler in a cell is
DNA
endocrine glands
Ductless glands that empty their hormonal products directly into the blood
polyribosomes
Free ribosomes forming groups of 10 to 20
lipid anchored proteins found extracellularly are held by
GPI anchor
organs
Groups of tissues that carry out related functions may form structures
transmembrane proteins
Integral proteins that span the membrane.
ways in which cell adhesion molecules work in body
NCAMs, help nerve cells creep across extracellular matrix its what allows white blood cells escape from circulation and move to infected tissues platelets to cling to damaged blood vessels
cervix consists of secretory and protective epithelial. they come together at the opening of cervix. HPV (human pap. virus) cause the cervical cells to develop dysplasia
NOTES
intracellular transport of cytoskeleton is especially important for which system of body
This function is particularly important in cells of the nervous system, where material must be transported over intracellular distances as long as a meter.
How can urine, stomach acid, and saliva have pH values outside the pH range that is compatible with life and yet be part of the living body?
Urine, stomach acid, and saliva are all inside the lumens of hollow organs, where they are not part of the body's internal environment
rheumatoid arthritis
a chronic autoimmune disorder in which the joints and some organs of other body systems are attacked by lysosomes
basal lamina (basement membrane)
a layer of filaments and fibers that attach an epithelium to the underlying connective tissue acellular matrix layer that is secreted by epithelial cells
neurofilament
a neural fiber
unusual thing about mitochondria other than that it has DNA
ability to replicate themselves even when the cell to which they belong is not undergoing cell division.
plasticity
ability to specialize into a cell of a type different from the type for which they were destined
dysplasia
abnormal growth or cell multiplication a change in size and shape of cells that is suggestive of cancer
A large number of ________ are associated with the cell's protein fibers
accessory proteins
phospholipid matrix on skin
acts as skins waterproofing agent
Cell-cell anchoring junctions take the form of
adherens junctions desmosomes
adipose tissue composition
adipocytes (fat cells)
advantage and disadvantage of compartmentation?
advantage: allow different environments to have different physical properties without disrupting each other's functions ex: lysosomes acidic environment could kill cell if it breaks disadvantage: harder to transport thins from one part of the cell to the other
lumen is filled with
air or fluid
nuclear pore complexes
allow communcation between nucleus and cytosol ions and small molecules more freely across but transport of proteins and RNA requires energy
how does the cytoskeleton restricting movement of integral proteins affect the cell?
allows cells to develop polarity, in which different faces of the cell have different proteins and therefore different properties. which is important in the cells of the *transporting epithelial*
why is nuclear pore complex so specific?
allows the cell to re- strict DNA to the nucleus and various enzymes to either the cytoplasm or the nucleus.
mechanical properties of tissue (elasticity and flexibility) depend on
amount and consistency of the tissues matrix
lipid anchored proteins
an amino acid of the protein is covalently attached to a lipid
leaky epithelium
anchoring junctions allow molecules to cross the epithelium by passing through the gap be- tween two adjacent epithelial cells ex: wall of capillaries
improper _______ junctions can lead to ..... why?
anchoring; metasis Cancer cells lose their anchoring junctions because they have fewer cadherin molecules and are not bound as tightly to neigh- boring cells secretes protein-digesting enzymes known as proteases (matrix metalloproteinases (MMPs)) that attack extracellular environment
basal body
anchors the cilium or flagellum
transporting epithelia: membrane modifications
apical vs basolateral side
neurons
are a lot of nerve cells that carry information in the form of chemical and electrical signals from one part of body to another
protective epithelia are found where
are found on the surface of the body and just inside the openings of body cavities epidermis linings of: mouth pharynx esophagus urethra vagina
Ciliated epithelia
are located primarily in the airways of the respiratory system and in the female reproductive tract nontransporting tissues surface of tissue facing lumen is covered with cilia
cell adhesion molecules (CAMS)
are membrane-spanning proteins responsible both for cell junctions and for transient cell adhesions
kinesins
assist the movement of vesicles along microtubules.
dynein
assist the movement of vesicles along microtubules. associate with the microtubule bundles of cilia and flagella to help create their whiplike motion
anchoring junctions
attach cells to each other or to the extracellular matrix
tendon
attach skeletal muscles to bones
desmosomes
attach to intermediate filaments of the cytoskeleton - spot desmosomes (Small contacts between cells) - belt desmosomes (bands that encircle the whole cell)
fixed ribosomes
attached to the cytosolic surface of organelles
retrograde
backward movement of vesicles in golgi
acellular layer between epidermis and dermis
basal lamina
most epithelial attach to an underlying matrix layer called=....... through.....
basal lamina cell adhesion molecules
separate epithelial tissues are held together through
basal lamina proteoglycans
how is movement of cilia accomplished?
beat rhythmically back and forth when the microtubule pairs in their core slide past each other with the help of the motor protein dynein
flagella movement
beat rythmically wavelike movement when the microtubule pairs in their core slide past each other with the help of the motor protein dynein
why don't lysosomes destroy cells
because their enzymes only work in acidic conditions
where kidneys at
behind abdominal cavity, between peritoneum and bones and muscles of the back, just above waist level
myosins
bind to actin fibers and are best known for their role in muscle contraction
supporting connective tissue
bone + cartilage dense ground substance that contains closely packed fibers
osteoblast
bone-forming cell
where are neurons concentrated?
brain and spinal cord but include network of cells that extend to every part of the body
catalases
break down hydrogen peroxide into water and oxygen inside peroxisomes
temperature regulation in infants is linked to what type of fat
brown fat
fibrous extracellular matrix of bone is said to be .... because... in turn giving bone
calcified, it contains mineral deposits, calcium salts (calcium phosphate) rigidity
smallest blood vessels are
capillaries allow molecules smaller than proteins to pass between two adjacent epithelial cells
for transmemebrane proteins _____ may attach to the extracellular loops and _____ may attach to the intracellular loops
carbohydrates phosphate groups
cell adhesions are weak
cell junction
transporting epithelia can be identified by what characteristics
cell shape membrane modifications cell junctions cell organelles
multipotent
cell with limited potential to develop into many types of differentiated cells Undifferentiated stem cells in a tissue that retain the ability to divide and develop into the cell types of that tissue are said to be ex: bone marrow and give rise to blood cells
cell-_____ and cell-_____ junctions stabilize the structure of tissues
cell-cell cell-matrix
tight epithelium
cells are bound to each other by tight junctions that create a barrier, preventing substances from traveling between adjacent cells. ex: kidney
necrosis
cells die from physical trauma, toxins, or lack of oxygen when blood supply is cut off - swell - organelles deterioriate - rupture digestive enzymes released damaged adjacent cells and cause inflammation - redness surrounding a scab
stronger cell junctions include
communicating junctions occluding junctions anchoring junctions
basal lamina
composed of a network of collagen and laminin filaments embedded in proteoglycans
brown fat
composed of adipose cells that contain multiple lipid droplets rather than a single large droplet
pemphigus
condition where cell starts attacking its junctions blisteing skin
ligament
connect one bone to another
primary tissue types in body
connective epithelial muscle neural
second major tissue type
connective tissue
Fibroblasts
connective tissue cells that secrete collagen rich matrix
GPI anchor
consists of a membrane lipid + a sugar phosphate chain
desmosomes can be recognized by the
dense glycoprotein bodies or plaques that lie inside cell membrane where two cells connect
strongest cell cell junction is
desmosome
______ anchor epithelial cell to each other
desmosomes (anchoring junctions)
smooth ER of liver and kidney
detoxify or inactivates drugs
3 families of protein fibers are classified by
diameter and protein composition
role of micelles
digestion and absorption of fats in the digestive tract
list of organ systems with lumen connected to external environment
digestive tract respiratory system reproductive system urinary system
plasma
dilute solution of ions and dissolved organic molecules, and soluble proteins basically ions organic molecules soluble proteins
gap junctions in nerve and muscle tissue allow for
direct and rapid conduction of electrical signals from cell to cell
why are capillaries considered leaky epithelium
dissolved molecules except for large proteins can pass from the blood to the interstitial fluid by traveling through gaps between adjacent epithelial cells.
mitochondria composition
double wall that creates two separate compartments within the mitochondrion mitochondrial matrix mitochondrial DNA inter-membrane space
tretinoin (Retin A)
drug derived from vitamin A speeds up cell division and surface shedding so treated skin develops a more youthful appearance
Most exocrine glands release their products through open tubes known as
ducts
motor proteins
dynein, kinesin
pleural sacs
each surround a lung
totipotent
earliest cells in human life are said to be this becuase they have the *ability to develop into any and all types of specialized cells *
loose connective tissue
elastic tissue that underlie skin and provide support for small glands
_____ microscopy allowed scientists to see the cell membrane for the first time
electron
epithelium lining lungs, blood vessels, and heart is also called
endothelium
mitochondrial matrix contains
enzymes, ribosomes, granules, unique DNA
the following defines what type of tissue: cover exposed surface (skin) line internal passageways (digestive tract) "Any substance that enters or leaves the internal environment of the body must cross _______"
epithelium
mucous secretions
ex: mucous sticky solutions containing glycoproteins and proteoglycans
insoluble protein fibers
ex; collagen, fibronectin, and laminin provide strength and anchor cells to the matrix
pap test
examination of cells taken from the cervix to detect early signs of cervical cancer
five functional types of epithelial
exchange transported ciliated protective secretory
epithelial origin of endocrine and exocrine glands
exocrine: epithelial tissue divides into connective tissue, forming a gland with ducts through which secretory substances pass through to get to external environment endocrine: epithelial divides into connective tissue, but loses neck region connection to parent epithelial, thus making secretions go straight into blood
chronic heart failure and metasis usually occurs because of
extracellular matrix disruptions
structure of connective tissue
extracellular matrix is a ground substance of proteoglycans and water that contain insoluble protein fibers
(T/F) mitochondrial DNA has the same nucleotide sequences as found in nucleus
false; different
(T/F) lysosome enzymes are always within the lysosome
false; sometimes they'll release enzymes outside cell to break down extracellular support material (ex: calcium carbonate portion of bone) cells allow their lysosomal enzymes to come in contact with the cytoplasm, leading to self-digestion of all or part of the cell. q
(T/F) All membranes have the same ratio of lipids to proteins
false; the ratio varies across cells
(T/F) Fixed ribosomes are always fixed
false; they can release and become free ribosomes
(T/F) Each cell in the body inherits identical genetic information in its DNA and therefore exhibit same function
false; they do inherit identical genetic information in its DNA, but no one cell uses all that information, which is why they have different functions
(T/F) Peripheral proteins disrupt membrane organization upon removal
false; they don't
(T/F) Cell adhesion are permanent, therefore bond between CAMs and matrix is strong
false; they're not permanent, weak bonds
fibrillin
fiber in connective tissue extracellular matrix (contain straight fibers)
protein fibers in matrix are.... what do they do?
fibronectin : connects cells to matrix elastin : stretch and recoil fibrillin : forms filaments and sheets collaged : stiff but flexible
keratin
fibrous protein found in hair and nails
macrophages
fight invaders like white blood cells
microvilli
finger-like extensions of cell membrane that increase the surface area of a cell for absorption of materials
cartilage composition
flexible lack of blood supply
collagen fibers
flexible but inelastic fibers whose strength per unit weight exceeds that of steel
flagella are found on
free-floating single cells - and in humans only male sperm is flagellated
a ____________ had revealed the actual three dimensional arrangement of lipids and proteins within the cell membranes
freeze-fracture electron micrograph
fluid mosaic model was a result of
freeze-fracture electron micrograph
Communicating junctions in animals are
gap junctions
nutrients in cytosol are stored as
glycogen granules and lipid droplets
extracellular surface of cell membranes has what type of carbs: ________ & ______
glycoproteins and glycolipids
matrix can be divided into
ground substance protein fibers
how to get through a tight epithelium?
have to go through cells, not in between the,
hollow organs include
heart, lungs, blood vessels, intestines
primary cilia in photoreceptors of the eye
help with light sensing
cytoskeleton: movement
helps cells move ex: cytoskeleton helps white blood cells squeeze out of blood vessels and growing nerve cells send out long extensions as they elongate. ex: Cilia and flagella on the cell membrane are able to move because of their microtubule cytoskeleton.
_______ tie epidermal cells to fibers of the basal lamina.
hemidesmosomes
cell-matrix anchoring junctions
hemidesmosomes focal adhesions
cell junctions
hold cells together in tissues
where can cholesterol be found in the membrane? what is their role?
inserted between phospholipids helps keep membrane *impermeable to small water-soluble* molecules and keeps *membranes flexible over a wide range of temperatures*
cytoplasm: protein fibers
insoluble form the cell's internal support system (cytoskeleton)
cytoplasm: inclusions
insoluble particles stored nutrients or materials responsible for specific cell function (non membraneous organelles)
inclusions
insoluble particles in cytoplasm
membrane proteins include
integral peripheral
ER composition function
interconnected membrane tubes with three major functions: synthesis, storage, and transport of biomolecules rough smooth
lumen
interior of any hollow organ
give an example of epithelial tissue (on an organ) that can alter tightness of their junctions according to body needs
intestine
where can lipid anchored proteins be found in the membrane
intra and extracellularly
focal adhesions
intracellular actin fibers to different matrix proteins, such as fibronectin.
why is blood such an unusual connective tissue
it's watery and doesn't have insoluble protein fibers present in other connective tissues
epithelial of skin and mucous membranes of the mouth act as barrier to
keep water in body invaders out (bacteria)
keratin and protective epithelial
keratin toughens protective epithelial
lipid rafts
lipids assembled in a defined patch in the cell membrane made of sphingolipids
biologists think that a _______ like structure was the precursor of the first living cell
liposome
______ are being used as a medium to deliver drugs and cosmetics through the skin
liposomes
gene therapy uses
liposomes to carry fragments of genes
nerve and muscle tissue have (little/lots) of extracellular matrix
little
cytoplasm: organelles
little organs membrane bounded
what organs do gap junctions appear in
liver, pancreas, ovary, thyroid gland
sphingolipids
longer fatty acid tail than phospholipids, have phospholipid or glycolipid head
types of connective tissue
loose dense adipose blood cartilage bone
connective tissue (cartilage, bone, and blood) has (lots/little) cellular matrix
lots
white blood cells include
lymphocyte neutrophil eosinophil
When muscles atrophy (shrink) from lack of use or the uterus diminishes in size after pregnancy, the shrinkage or disappearance is due to
lysosomes
lysosomal storage disease
lysosomes are ineffective because they lack specific enzymes ex: Tay Sachs disease
RER
main site of protein synthesis (on ribosome outside RER) then inserted into ER lumen where they undergo chemical modification
cells that have lost their ability to undergo cell division, such as....., don't have what?
mature nerve cells centrioles
intermediate filaments: size composition protein function
medium of all three (10nm) keratin and neurofilament (filament) cytoskeleton; hair and nails, protective barrier of skin
cytoplasmic vesicles
membrane bound 2 kinds: secretory and storage
what other structures exhibit hydrophobic and hydrophilic membranes
micelle liposome phospholipid bilayer
cell membrane
microscopic double layers (bilayers) of phospholipids with protein molecules inserted in them, separating ICF from ECF.
centrosome
microtubule organizing center assemble tubulin monomers into microtubule polymers contains 2 centrioles
cytoplasmic fiber types
mifrofilaments microtubles intermediate filamens
in ground substance we have
mineralized - bone gelatinous + syrupy - dense/ loose connective tissue, cartilage, adipose tissue watery - blood
four major groups of organelles:
mitochondria, the Golgi apparatus, the endoplasmic reticulum, and membrane-bound spheres called vesicles
transporting epithelia: cell junctions
moderately tight to very tight junctions. This means that to cross the epithelium, material must move into an epithelial cell on one side of the tissue and out of the cell on the other side.
collagen
most abundant protein in the body (1/3 of bodys *dry weight*) - most diverse of matrix fibers (12 variations) - found almost everywhere connective tissue is found - aggregate to form collagen fibers
paracellular pathway
movement of materials between cells
stratified epithelial
multiple cell layers
motor protein composition
multiple protein chains arranged into three parts - two heads that bind to the cytoskeleton fiber, a neck, and a tail region that is able to bind "cargo,
excitable tissues include... because
muscle and nerve their ability to generate and propagate electrical signals called action potentials
which has more mitochondria muscle or adipose tissue?
muscle; requires more energy
ciliopathies
mutation to ciliary proteins causes disorder ex: polycystic kidney disease loss of vision to cancer
where does the centrosome appear and what does it look like
near nucleus as a region of darkly staining material
what does accumulation of glyco lipids in nerve cells do
nervous system dysfunction, including blindness and loss of coordination
neural tissue cell types
neurons (nerve cells) glial cells (neuroglia)
storage vesicles
never leave cytoplasm
can an isolated pluripotent cell develop into an organism? what about totipotent?
no yes
Peroxisomal disorder disrupt....
normal processing of lipids and can severely disrupt neural function by altering the structure of nerve cell membranes.
cartilage is found in
nose, ears, knee, and windpipe
According to the original fluid mosaic model of the cell membrane, membrane proteins could move laterally from location to location, directed by protein fibers that run just under the membrane surface. However, researchers found that....
not all proteins behave this way some integral proteins have restricted movement due to proteins from cytoskeleton anchoring them down making them immobile.
the castle in a cell is
nucleus
internally the cell can be divided into
nucleus and cytoplasm
melanoma
occurs when melanocytes become malignant, often following repeated exposure to UV light. One study found that people who used tanning beds were 24% more likely to develop melanoma.
simple epithelial
one cell thick
Structure of Epithelia
one or more layers of cells connected to one another, with a thin layer of extracellular matrix lying between the epithelial cells and their underlying tissues
hard bone forms when....
osteoblasts deposit calcium phosphate in the matrix
exchange epithelial
permit rapid exchange of materials, especially gases
lipids of biological membrane are mostly ____, but also contain
phospholipids sphingolipids cholesterol
which lipid anchored enzyme is almost always associated with a lipid raft
placental alkaline phosphatase
extracellular fluid is further divided into
plasma (fluid portion of blood) interstitial fluid (surrounds most cells of the body)
dividing wall between ECF and ICF
plasma membrane
synonyms for cell membrane
plasma membrane, plasmalemma
intermembrane space of mitochondria
plays an impor- tant role in mitochondrial ATP production,
distinguishing characteristic of connective tissue is....
presence of extensive extracellular matrix containing scattered cells that secrete and modify the matrix
Protective epithelia
prevent ex- change between the internal and external environments and protect areas subject to mechanical or chemical stresses
tight junctions in intestines and kidney
prevent most substances from moving freely between the external and internal environments
secretion
process by which a cell releases a substance into the extracellular space
Differentiation
process in which cells become specialized in structure and function by only turning on specific genes
Surface keratinocytes
produce keratin fibers
apoptosis
programmed cell death don't disrupt neighbors when die chromatin in nucleus condenses shrink breaks and digested by neighboring cells or immune cells
transporting epithelia: cell organelles
properties differ depending on where in the body the epithelia are located. ex: glucose can cross the epithelium of the small intestine and enter the extracellular fluid but cannot cross the epithelium of the large intestine.
matrix metalloproteinases (MMPs)
protease secreted by cancer cells to dissolve ectracellular matrix this provokes metasis, scientists are investigating how to stop it
epithelial tissues (epithelial)
protect the internal environment of the body and regulate the exchange of materials between the internal and external environments
Epithelial tissues provide.....
protection and regulate exchange
glycocalyx
protective layer including carbohydrates, found on external surface of a plasma membrane that is important for cell-to-cell communication
nucleoli
protein contain the genes and proteins that control the synthesis of RNA for ribosomes
movement in the body happens through
protein fibers and motor proteins
cytoskeleton: cell shape
protein scaffolding of cytoskeleton provides *mechanical strength* and gives cell shape
a great example of how compartmentation allows seperation of function is seen in:
protein synthesis, modification, and packaging
would the inner membrane of the mitochondria which contains enzyme for ATP production have more protein or lipid?
protein, a third is proteins
in general, the more metabolically active a membrane is, the more _____ the membrane contains
proteins
most inclusions with functions (other than those used for nutrient storage) are made from
proteins or combination of protein and RNA
motor proteins definition types
proteins that are able to convert stored energy into directed movement. myosins kinesins dynein
basic components of matrix
proteoglycans and insoluble protein fibers
dense connective tissue
provide strength or flexibility ex: tendons, ligaments, sheaths that surround muscles and nerves
connective tissue
provides structural support and physical barrier that help defend body ex: blood, support tissue for skin and internal organs, cartilage and bone
phosphorylation is used to do what in proteins
regulate/alter protein function
exocrine glands
release their secretions to the body's external environment can be to surface of skin or epithelium lining one of the internal passageways (airway of lungs or lumen of intestine) ex: sweat glands, mammary glands in the breast, salivary glands, the liver, and the pancrease
Connective tissue cells can be fixed or mobile in the ECM, where fixed cells are responsible for.... and mobile cells are responsible for....
responsible for local maintenance, tissue repair, and energy storage responsible mainly for defense
free ribosomes
ribosomes suspended in the cytosol
example of exocrine gland that secretes both serous and mucous secretions
salivary gland
cytoplasm: cytosol
same as ICF semi-gelatinous fluid dissolved nutrients proteins ions waste products
The ______ is an excellent example of an organ that incorporates all four types of tissue into an integrated whole.
skin
how do nutrients and oxygen reach cartilage if there's no blood supply?
slow diffusion, which is why damaged cartilage heals slowly
micelles structure
small droplets with a single layer of phospholipids arranged so that the interior of the micelle is filled with hydrophobic fatty acid tails.
lysosomes
small storage vesicles that appear as membrane bound granules in cytoplasm *digestive system of cell* use powerful enzymes to break down bacteria or old organelles if any material can be reused, it'll be dumped back into the cell, else it'll be dumped outside of it
RIbosomes
small, dense granules of RNA and protein that manufacture proteins under the direction of cell DNA
all fibers are polymers of
smaller proteins
how can cilia be damaged
smoking paralyzes the ciliated epithelium lining the respiratory tract higher incidence of respiratory infection in smokers, when the mucus that traps bacteria can no longer be swept out of the lungs by the cilia.
lipid anchored proteins are found to be associated with
sphingolipids
thoracic is bound by
spine and ribs on top and sides, with the muscular diaphragm forming the floor
metasis
spread of cancer cells through circulatory system and lymph vessels
types of epithelial cell shape
squamous (flattened) cuboidal columnar
peroxisomes
storage vesicles that are even smaller than lysosomes degrade long- chain fatty acids and potentially toxic foreign molecules process within generate hydrogen peroxide (Toxic molecule), but broken down with catalase within peroxisome
adipocytes
store energy in fat
SER in skeletal muscles
stores calcium ions to be used for muscle contraction
protective epithelia structure
stratified
hemidesmosomes
strong junctions that anchor intermediate fibers to fibrous matrix protein (laminin)
glycolipids and glycoprotein functions include
structural stability cell recognition immune response
purpose of protein fibers (microfilaments, intermediate filaments, and microtubules) ?
structural support (cytoskeleton) and movement
histology
study of tissue structure and function
apical membrane
the surface of an epithelial cell that faces a lumen, such as that of the intestines has microvilli that increase surface area
cells in protective epithelium have a short life span because
subject to bacteria and chemicals
glial cells (neuroglia)
support cells for neurons
pericardial sac
surrounds the heart and helps prevent overfilling.
examples of things epithelial transfers to environment are
sweat and saliva
Secretory epithelia
synthesize and release secretory products into the external environment or into the blood.
fibroblasts
synthesize extracellular fibers
mitochondrial replication
takes place by budding small daughter mitochondria pinch off from an enlarged parent ex: exercising muscle cells that experience increased energy demands over a period of time may meet the demand for more ATP by increasing the number of mitochondria in their cytoplasm.
which has more restricted movement, ligament or tendon? why?
tendon because they lack elastic fibers, while ligaments have elastic fibers and collagen
epidermis
the skin surface is a mat of linked keratin fibers left behind when old epithelial cells die.
Why do mitochondria contain DNA when other organelles do not?
theory: mitochon- dria are the descendants of bacteria that invaded cells millions of years ago. The bacteria developed a mutually beneficial re- lationship with their hosts and soon became an integral part of the host cells. Supporting evidence for this theory is the fact that our mitochondrial DNA, RNA, and enzymes are similar to those in bacteria but unlike those in our own cell nuclei.
exchange epithelial structure lines..... why? categorized as (simple/stratified) with cell shape of (Squameous/cuboidal/columnar)
thin flattened cells lines blood vessels, heart and lungs; because two major sites of gas exhcnage in the body simple squamous
membranes such as peritoneum, pericardial, and pleural are made of what
thin, translucent layers of cells.
microfilaments: size composition protein function
thinnest of all three (7nm) actin (globular) cytoskeleton; associated with myosin for muscle contraction
what type of cells have more ribosomes than normal?
those that synthesize proteins for *export* out of the cell.
Occluding junctions in vertebrates
tight junctions
blood brain barrier
tight junctions that prevent harmful substances in blood from reaching extracellular fluid of the brain
integral proteins
tightly bound to the membrane and can only be removed through detergents or other harsh methods that destroy membrane integrity ex: transmembrane, lipid-anchored
how are membrane proteins bound to the membrane?
tightly, but not covalently (strong noncovlaent interactions with the tails of the phospholipids
peritoneum
tissue lining (membrane) that lines the abdominal cavity and the organs within it (stomach, intestines, liver, pancreas, gallbladder, and spleen)
(T/F) A cell with microvilli has at least 20 times the surface area of a cell without them.
true
(T/F) Anchoring and tight junctions both allow movement of solutes from one side to other, tight junctions is just more restrictive
true
(T/F) Connective tissue cells can produce proteoglycans or fibers
true
(T/F) Inclusions are in direct contact with the cytosol
true
(T/F) Most cells that transport materials have numerous mitochondria to provide energy for transport processes
true
(T/F) Some cytoskeleton protein fibers are permanent, but most are synthesized or disassembled according to the cell's needs.
true
(T/F) an individual cell can carry out all the processes of life.
true
(T/F) extracellular material varies from tissue to tissue
true
(T/F) most cells have a single short cilium
true
(T/F) primary cilia play a role during embryonic development
true
(T/F) proteins in the cell membrane hold the cytoskeleton in place to maintain cell shape
true
(T/F) All cells in the body are derived from the single cell formed at conception.
true :O
(T/F) material in the lumen is not truly part of the body's internal environment until it crosses the wall of the organ
true :o
(T/F) mitochondria manufactures own proteins
true; has its own DNA
(T/F) E. coli doesn't harm the body when in large intestine
true; it doesn't affect the body unless a disease causes a puncture in the large intestine and e.coli goes into internal of body
(T/F)vesicles bud off golgi to become lysosomes
true; sometimes
(T/F) the number of mitochondria in a cell is directly related to the cell's energy needs.
trye
Immunoliposomes
use antibodies to recognize specific types of cancer cells and deliver drugs to cells sceintists are treating
serous secretions
watery solutions with enzymes ex: tears, sweat and digestive enzyme solutions