LEARNING OBJECTIVES
- Read the Class Notes, using the Textbook
illustrations to help understand the concepts. Read the chapter using the
Class Notes as your guide. There are many questions included
to help tie the systems and concepts together into an integrated,
holistic understanding of anatomy and physiology.
- Take the
Ch.
4 self test in the online textbook.
DO NOT EMAIL THIS TEST TO YOUR INSTRUCTOR. It is a learning tool
only. These tests will also include
questions that are NOT covered in this course.
- Use any resources on the
Online Textbook,
to integrate your learning.
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Chapter 4: Tissues
Use the diagrams in the book to enhance
comprehension of these concepts.
ALL of the human body is made up of just 4 (four!) types
of tissues. In this section, the student will learn the basic
characteristics and functions of each tissue type and how it relates to
maintaining homeostasis.
What are the levels of organization?
Review Chapter 1
Cell Theory says that:
Cells are the building block of all living things and tissues. Just like
bricks are the building blocks of walls, and four walls and a roof create
a room – cells are the building block of tissues and several tissues
create an organ.
Cells are the lowest level of organization at which the
characteristics of life occur.
Cells come from preexisting cells. You cannot buy a box
of organelles, take it home and ‘mix up some cells’ - a living cell has
to produce another living cell.
Review Chapter 3, Cell Theory
A tissue is a group of cells that have the same
shape and function.
What are the building blocks of all tissues?
How are the cells that make up a tissue similar?
Glands - a cell or group of cells (tissue) that make a
product or substance and secrete that
product/substance.
Glandular cells, because they secrete
substances, often have villi or microvilli to increase
the
surface area of the cell membrane.
Two types of glands in the body (depends on where the product goes once
it is secreted)
Exocrine - secretes its product through a duct onto
an epithelial surface.
Endocrine - secretes its product into the extracellular fluid.
What are the two types of glands in
the body?
Where does each secrete it's product?
How is a gland classified as either 'endocrine' or 'exocrine'?
How do villi support secretion of a substance?
Describe the four major categories of tissues and give
general characteristics of each
List the 4 types of tissues
Epithelial Tissue - ALWAYS has a free surface.
Found where ever there is a SURFACE.
Connective Tissue - found all over the body.
Always has extracellular proteins and specialized cells in a 'Matrix'.
Muscular Tissue - the cells can contract.
Nervous Tissue - the cells can conduct an
electrical charge (an ACTION POTENTIAL).
Epithelial tissue - Describe the function of each,
depending on the location
Describe the construction of an epithelium.
What two characteristics distinguish
and epithelium from the other types of tissues?
Free surface and Basement membrane. Describe the structure of an
epithelium – draw it!
What is
simple vs stratified?
Two types:
Simple - the surface is a
SINGLE layer of cells
Stratified - the surface is MANY layers of cells
List the three cell shapes and the general function of
each.
squamous cells - protection
cuboidal cells - secretion (glands)
columnar cells - absorption (nutrients)
Because cuboidal cells usually are secretory, and
columnar cells usually are absorptive, these epithelia are usually simple,
and have microvilli and or cilia.
Where in the body do you find epithelia with each cell
type?
What is the function of that body structure?
What is the function of villi (microvilli)?
Review Chapter 3, Cells.
List the type of cells on which you
would expect to find villi.
Where in the body would you expect to find epithelia with cells
that have villi?
Digestive System - absorption of nutrients.
Glandular cells - secretion
Exocrine
Endocrine
List the three common epithelium types and the general
function of each.
simple squamous vs
stratified squamous
simple cuboidal vs
stratified cuboidal
simple columnar vs
stratified columnar
What are the characteristics of each?
The function of the integumentary system is to protect against water
loss, abrasion, infectious diseases, etc. Therefore, it is made of
a stratified squamous epithelium.
The function of glands is to secrete, therefore it has a simple cuboidal
epithelium.
The function of the digestive tract is to absorb nutrients, therefore it
is a simple columnar epithelium.
The function of capillaries is exchange of nutrients between blood and
the tissues, therefore the walls of
capillaries are simple squamous epithelium.
The function of the alveoli is to exchange oxygen and carbon dioxide
between air and blood, therefore
the wall of the aveoli is simple squamous epithelium.
Simple squamous epithelia are found:
wall of capillaries
wall of alveoli
lining the blood vessels and heart
the membranes lining the internal body cavities (peritoneum,
pleura, pericardium, etc)
Simple cuboidal epithelia are found:
Glands
Simple columnar epithelia are found:
small and large intestines
Stratified squamous epithelia are found:
where the chance of physical and chemical abrasion, etc is high -
such as the
skin - integumentary system,
cutaneous membrane
lining of the mouth
pharynx
esophagus
vagina
glans penis, etc.
Describe a psuedostratified, columnar, ciliated
epithelium.
Where is it found?
What is its function?
Describe a transitional epithelium.
Where is it found?
What is its function?
What are Goblet cells?
Where are they found and what is their function?
What are the two main types of glands in the body?
What happens to the secretions from an exocrine gland?
What happens to the secretions from an endocrine gland?
Give some examples of each type gland.
The alveoli are the structures in the lungs where O2
diffuses from the air into the blood, and CO2 diffuses from blood into the
air.
Capillaries are the tiniest blood vessels where exchange of nutrients
(sugars, proteins, lipids, CO2, O2, etc) between blood and the cells that
make up the tissues.
The wall of the Alveoli and the Capillaries is a simple squamous
epithelium. The WALL of the Alveoli and Capillaries must be very
thin, to support the exchange of nutrients and gas molecules. This
anatomy means that the nutrients only have to pass through a single layer
of cells when diffusing. The FUNCTION of the alveoli and capillaries
is 'exchange of materials between blood and other tissues/air' - and the
structure of the wall supports this function.
Describe the structure of the wall
of the capillary.
Describe the structure of the wall of the alveoli.
List the types of cell junctions.
What is the structure and function of each junction
type?
tight junction - holds cells together, the
outermost lipid portions of the adjacent cell membranes
are fused
desmosomes -
gap junction or intercalated disc - allows the cytoplasm
of one cell to directly contact the cytoplasm of an adjacent cell.
Connective tissue (CT) - Describe the functions of each
type of CT and relate each CT type to the function of the body or an organ
system
Connective Tissue is made up of specialized cells, extracellular proteins
and ground substance. You need to know the general characteristics of each
CT type. In general, CT has MANY functions – but each type has only one
major function.
Connective Tissue connects all the parts of the body to one another. All
the cells are connected by CT; all the organs are connected by CT; all the
organ systems are connected by CT.
The specific function of a CT type depends on the MATRIX
of that CT. The matrix is the most common component of a system.
A grassland is called a GRASSland because the main
component is grass – the matrix is ‘grass’. A Forest is a forest – why?
What is the matrix of a forest?
Blood is a liquid because it has LOTS of water and cells
and relatively fewer extracellular proteins – in addition, the
extracellular proteins are NOT attached to other structures.
What is the matrix of blood?
Bone on the other hand is a solid because there is lots of
Ca and P bonded together with collagen fibers and relatively few cells and
water.
What is the matrix of bone?
These are examples of the two extremes of CT matrix. The
other CT types have shape and MATRIX characteristics in between these two.
Why is the shape of the matrix
important?
The ground substance of the CT includes the Matrix,
matrix molecules, extracellular proteins and specialized cells.
The Matrix molecules are
Hyaluronic acid - Hard, SLIPPERY -
reduces
friction and creates a tough durable surface.
Proteoglycan - hydrophilic. This is a 'tree branched' molecule
with lots of
water stuck in between the branches.
The SHOCK
ABSORBER molecule.
Specialized cells - create or break down the CT.
Each type of CT has its own
specialized cells: blood has blood cells, bone
has osteocytes, etc.
Extracellular Protein Fibers - each type of protein
gives CT a particular 'ability'
Collagen fibers - VERY strong. will not stretch.
Gives CT a great deal of strength.
Reticular fibers - thin collagen fibers, found in areolar loose
connective tissues in the interstitial spaces (between each individual
cell)
Elastin fibers - ELASTIC - stretchable. Give CT and
tissues the ability to Stretch and return to it's normal size.
List the major types of connective
tissue, the function, the matrix characteristics and where each CT is
located.
Connective Tissue Proper
Loose CT - contains reticular and collagen fibers in a
WATERY ground substance (hence the term 'loose').
Two types
areolar loose CT - the most common CT in the body,
found in between and surrounding most cells. Structural support,
holds the cells/tissues together.
adipose tissue - adipocytes; store fat (lipids) for energy, found
in most membranes. Energy storage.
Dense CT - very little water. Mostly collagen
fibers. Fibrocytes.
Two types.
regular dense CT - found in tendons (attaches
muscles to bones) and ligaments (attaches one bone to the next). Lots of
collagen fibers all running in 1 (one) direction - very strong in one
direction.
Irregular dense CT - found in the Sheaths and Capsules around
hollow organs. Lots of collagen fibers running in ALL directions -
strong in all directions. Gives structure to the hollow organs,
keeps the organ from rupturing.
Fluid CT - matrix is Water - with NO collagen, elastin or reticular
fibers. Instead
contains the 'blood proteins.
Two types
Blood - RBCs and WBCs. Found in blood
vessels. Transports nutrients around the body.
Lymph - lymphocytes Found in lymph vessels. Transports
hormones and other extracellular substances to the vascular system.
Lymphocytes defend the body against pathogens.
Structural CT - Mostly collagen with matrix molecules
Two types
Bone - Collagen embedded in bone salts (hydroxyapatite,
Ca and P)
highly vascularized
- therefore, it heals quickly
Cartilage - Collagen embedded in hyaluronic acid and proteoglycans
very little
vascularization - Heals slowly, poorly.
Three types
Fibrocartilage - LOTS of collagen - REAL strong and
durable.
Found in the pubic symphysis and intervertebral discs.
Elastic cartilage - LOTS of elastin fibers - found in the external
ear, nose, etc.
Hyaline cartilage or Articular Cartilage- THE most common
cartilage in the body. LOTS of hyaluronic acid - REAL
durable,
glasslike and SLIPPERY. Found at the ends of long
bones - where the
bones articulate with each other.
Bone is highly vascularized with capillaries embedded
within the bone
tissue and heals more rapidly than cartilage, which gets its
nutrients from
capillaries on the surface of the cartilage. The
nutrients must diffuse into
the cartilage - a process that is SLOW and inefficient.
This is why it is better to 'break a bone, than strain, sprain, or tear a
tendon,
ligament, or cartilage.
What is the matrix of each?
Which has the most water in the ground substance?
What is the function of blood and the cardiovascular system?
Which characteristics of water supports these
functions?
Which has the least water in the ground substance?
Which has the most collagen? the least collagen?
Which has the most elastin?
How does the amount of water and collagen/elastin and hyaluronic acid/proteoglycan
determine the function of each CT?
What is the function of hyaluronic acid? of proteoglycan?
What is the most common CARTILAGE in the body?
Why does bone heal more quickly than cartilage?
List the specialized cells for each type of Connective
Tissue.
Fibrocyte, fibroblast, fibroclast - these cells are
found in CT with lots of fibers
Red blood cells, RBC, erythrocyte - found in blood
White blood cells. WBC, leucocyte:
Neutrophil, Eosinophil, Monocyte - PHAGOCYTES
What is the function of
phagocytes?
Basophil - (mast cells) secrete histamine and heparin
Mast cell - this is a BASOPHIL that is located in
CT attached to collagen/reticular
fibers. Secretes histamine and heparine when
collagen/reticular fiber is damaged.
Adipocyte - energy (fat) storage
Phagocyte, macrophage, microphage - immune system cells - WBCs and
Lymphocytes; remove dead cells, foreign cells
(Pathogens), and cellular wastes and
debris from interstitial fluids
Osteocyte, osteoblast, osteoclast - cells found in bones. Construct
the hydroxyapatite
crystalline structure with Ca and P, the bone
salts.
Chondrocyte, chondroblast, chondroclast -
What does 'chondro' mean?
Cartilage
Reticulocyte
-blast - a cell that BUILDS a CT. A fibroBLAST creates
fibers. What does an osteoblast do?
-clast - a cell that BREAKS DOWN a CT. A fibroCLAST breaks
down fibers. What does an osteoclast do?
-cyte - This is a MATURE cell - that maintains a CT. A fibrocyte
maintains fibers. A '-cyte' can have both anabolic and catabolic
functions. What does an osteocyte do?
What does a chondrocyte do?
What does a reticulocyte do?
List the extracellular proteins found in each
CT type.
What is a mast cell?
What is its function?
Hyaluronic acid and proteoglycan are matrix molecules.
What is the function of each?
Each matrix molecule gives the CT matrix a unique characteristic and
therefore a specific function.
Make a TABLE of the major types of CT for compare and
contrast.
Why is bone ‘easy’ to repair, but cartilage is difficult
to repair?
Define vascular and avascular.
Is bone vascular or avascular?
Is cartilage vascular or avascular?
How does this affect repair of a broken bone, and of a torn cartliage?
Why?
What is the function of 'blood'?
IF there is no vascular system, then no blood reaches that tissue.
What is the function of Adipose
tissue?
What are the cells that form adipose tissue called?
Describe
Membranes
Epithelial and Connective tissues make up Membranes.
What is a ‘membrane’?
Plastic wrap such as ‘saran wrap’ is
a membrane. When you stretch it over a bowl, there is a free surface
toward the stuff in the bowl , the environment inside the bowl. There is a
free surface toward the conditions (or environment) outside the bowl. The
‘membrane’ separates the two environments from each other.
How is the cell membrane a ‘membrane’?
Membranes have a free surface - Epithelium!
List the four types of membranes in the body:
What is the cutaneous membrane?
What is a mucous membrane?
What is a serous membrane?
What is a synovial membrane?
Which membranes are normally ‘dry’ and which are normally
‘wet’.
Which two membranes are exposed to conditions OUTSIDE the
body?
Which are normally exposed to conditions INSIDE the body?
What is in contact with the ‘free border’ of each?
What is the primary characteristic(s) of each?
How does the membrane’s location in the body affect the
structure of the membrane?
Make a TABLE so that you easily compare and contrast
membrane characteristics and functions.
| cutaneous |
dry |
OUTside of body |
integumentary system |
| mucous |
wet |
OUTside |
mouth, digestive tract, nasal, oral, vagina |
| serous |
wet |
INside |
peritonium, pleura, pericardium |
| synovial |
wet |
INside |
joint cavities |
Which membranes are exposed to
conditions OUTSIDE the body?
Which membranes are exposed to conditions INSIDE the body?
How does this affect the STRUCTURE of the surface?
Which is stratified and which is simple?
Why?
Describe the structures on cell membranes that support secretion and
absorption in the
digestive system.
Describe the location of pleural membranes, pericardial
membranes, the meninges, and the perineum-mesentery
Remember chapter 1, the body
cavities and the membranes that line them?
These are SEROUS membranes! The function is to
reduce the friction between the organs inside the body cavity and the wall
of the body cavity. This allows the organ to move without damage.
These membranes produce serous fluid which lubricates the
membrane and allows each to slide passed each other.
How is 'visceral membrane' vs
'parietal membrane' related to reducing friction?
List the serous membranes.
State the location of mucous membranes and state the
function of mucus
What do mucous membranes produce?
What are the components of mucous?
What is the function of mucous?
Name some membranes made of connective tissue
Hint 1: review the membranes that line the body cavities.
Hint 2: review the characteristics of ‘epithelial tissues’
and their construction.
Muscle tissue - Explain the basic differences between
smooth, skeletal and cardiac muscle
What is the function of muscle tissue?
What characteristic of the muscle cell produces this
function?
What type molecule is it?
Hint - it is one of the organic molecules.
What is an organic molecule?
Why is an organic molecule called ‘organic’?
Again - make a TABLE to compare the 3 types of muscle
tissue!
4 columns titled: characteristic, smooth muscle, skeletal muscle, cardiac
Characteristics for comparison:
striated vs unstriated;
length;
location in body;
number of nuclei,
Innervation - voluntary vs involuntary,
NOTE: cardiac muscle has intercalated discs, and the muscle cells branch.
Intercalated discs are GAP junctions between cells.
These allow the cytoplasm of one cell to directly contact the cytoplasm of
the adjacent cell. Review
Cell Junctions.
Which type of muscle tissue is NOT
striated?
Which type of muscle tissue is multinucleate?
Which type of muscle tissue has intercalated discs and branched cells?
Which type of muscle is located in the wall of hollow organs?
Nervous tissue - Describe in brief nervous tissue
What is the function of Nervous tissue?
Nervous tissue conducts an electrical charge called an ACTION POTENTIAL.
This means that nerve cells communicate with each other and control other
cells. Your body uses this ability to send a 'signal' from one cell
to the next as a means of sensing and responding to it's environment.
Nervous tissue is made up of two types
of cells:
Neurons - the functional unit of nervous tissue - the cell that
actually transmits the action potential.
Dendritic nerve
endings
Dendrite
Soma
Axon hillock
Axon
Presynaptic knob or
terminal
Neuroglia - the
cells that support, maintain, and nourish Neurons.
Astrocytes
Microglia
Ependymal cells
Oligodendrocytes
Satellite cells
Schwann cells
Describe a neuron and its function. Draw and label the
parts of the neuron.
What is a neuroglia?
List the different types of neuroglia and the
function of each.
Name the organs made of nervous tissue
Brain
Spinal cord
Nerves
Describe the Action Potential, Na/K pump, Resting Membrane Potential
You will have to look in the chapters on the muscular
system and nervous system for the following – read over it and get a
‘feel’ for what is going on.
How does the nerve ‘transmit’ a signal?
Start with a RESTING cell. The cell is resting – i.e. not stimulated,
not excited, just waiting just 'resting'.
The CM of the cell has a resting membrane potential (RMP). This refers to
the electrical charge difference across the CM.
What does this mean?
Measure the electrical charge in the extracellular
fluid, then measure the electrical charge in the intracellular fluid. At
RMP, the intracellular electrical charge will be about 70 mV less than the
electrical charge of the extracellular fluid. I.e. there is different
electrical charge on each side of the CM – when the cell is not excited
(responding) the CM is at RMP. The system is
NOT at equilibrium – there is a POTENTIAL for movement of charges.
Think about it this way:
on a number line starting with 0 ...
0--1--2--3--4--5--...... --
20--21--...68--69--70--71--72--...--88--89--90--91 --->infiniti
How far is 0 from
70? 70 units, yes?
How far is 20 from 90? 90 - 20 = 70
units, yes?
The units in RMP is milli Volts - mV.
The difference (extracellular electrical charge - intracellular electrical
charge) in electrical charge is 70 mV apart!
By convention, the standarized method for calculating the difference
produces the negative sign. So do not worry about that.
Just know that the RMP is -70mV. And
that when you measure the electrcal charge of the extracellular fluid and
compare it with the electrical charge of the intracellular fluid - the
intracellular fluid is 70 mV different from the extracellular fluid.
NOW - WHAT
maintains this RMP, this -70 mV potential difference??
The Sodium / Potassium pump! the
Na/K pump
What is the sodium/potassium pump? (Na/K pump)
What is its function?
This is an ACTIVE transport
process- what does that mean?
In a ‘resting’ cell which ion is inside the cell?
Which ion is in the extracellular fluid?
What does this create?
Remember the RMP from just above?
Hint- high concentration of Na+ outside vs. low concentration
of Na+
inside –
what does Na+ try to do?
Where is the highest concentration of K+?
What does K+ want to do?
The Na/K pump is an active transport process that uses
energy to move 3 Na OUT of the cell and 2 K INTO the cell. Because
it is moving both Na and P against their respective concentration
gradients, this creates a steep, POTENTIAL gradient for the movement of
Na into the cell, and K out of the cell. Remember, when a gradient
exists, the solute with a gradient WANTS to DIFFUSE! The CM
prevents that movement.
What is the function of the CM?
What is the characteristic of
ions, that allows the CM to form a permeability
barrier to their movement?
Both Na and K are cations, they have + electrical charges. The
Na/K pump moves 3 + OUT but only 2 + in! This means that there are
more + in the extracellular fluid --> an electrical gradient --> there
is the POTENTIAL for movement of the electrical charge, too (in addition
to the potential for movement of the Na and K ions).
Because both Na and K are ions, they have a charge and
are therefore hydrophilic - can dissolve in water. The CM, made of
a phospholipid bilayer, is a permeability barrier to water and other
polar atoms and molecules. The only way that Na and K can pass
through the CM is to move through channel proteins.
What is an action potential (AP)?
Remember the number line from above?
An AP is -35mV. The intracellular and extracellular electrical
charges are ONLY 35 units (mV) apart!
They are closer to equiilbrium! I.e. the charge difference is closer to
'zero' - or, in other words - the electrical charge on each side of the CM
is close to being equal!
-35 mV is the Threshold at which an AP
is produced - The Cell is STIMULATED - it is EXCITED. It RESPONDS to some
'condition'.
What is a ‘threshold’? Define it.
When the Potential is -35 or less - the cell is
stimulated. When the Potential is greater than 35 mV, the cell is NOT
stimulated.
What happens when the membrane potential (electrical
charge difference between the inside and outside of the CM) drops to –35
mV?
What is the AP?
It is that ELECTRICAL signal that neurons conduct. It is that
electrical signal that your body uses to transmit information and
commands. When a 'sensor' neuron is stimulated, it produces an AP that
tells your body that a particular 'condition' exists. When a
'motor' neuron is stimulated, that signal produces a RESPONSE to some
condition.
When the RMP drops from -70 mV to -35 mV, the cell is stimulated or
excited, and 'responds' to it's environment (remember those
characteristics of life?)
What is acetylcholine (ACh)?
What is a neurotransmitter?
Acetylcholine is the neurotransmitter for the neuromuscular junction.
The neuromuscular junction is the junction between a neuron and a muscle -
the neuron 'stimulates' a muscle to contract.
What is it’s function?
Where is it stored in the presynaptic knob?
List the parts of the neuromuscular junction.
What is acetylcholinesterase (ACh-ase, or ACh-esterase)?
NOTE - this word ends in '-ase'. this indicates that it is an
ENZYME.
What is an enzyme?
What is the function of an Enzyme?
What is the sum of all chemical reactions in the body?
What is the function of acetylcholinesterase?
What is the post synaptic membrane?
What are the 6 types of proteins in the membrane (from
chapter 3).
What are the two basic types of channels?
Of the ‘gated’ channels – what are ligand gated and
voltage gated channels?
What is ‘gate’?
When a 'gated channel' is stimulated (excited), the gate
opens, and an ion or molecule can pass through the channel. Each channel
is SPECIFIC for a specific atom or molecule. A K channel will ONLY
allow (fit) K ions. A Ca channel will only allow Ca to pass
through. A GATED channel will only allow it's atom to pass
through, when the gate is 'open'.
So... what opens the gate?
What stimulates ligand gated channels?
What stimulates voltage gated channels?
A ligand gated channel responds (is stimulated by)
a specific chemical (atom or molecule). Each ligand gated channel is specific to one type of molecule or atom.
Only that particular atom of molecule can pass through, attach to, or be
transported by that specific ligand gated channel.
There are ligand gated Na+ channels; ligand gated Ca++ channels; ligand
gated K+ channels, etc.
A voltage gated channel responds to a particular
voltage, or electrical charge.
What is the electrical charge that excites a voltage
gated channel?
What passes through voltage gated K+ channels?
There are voltage gated Na+ channels; voltage gated Ca++ channels,
and so on.
Make a TABLE to compare the different types of Channels.
Describe the Inflammatory
Response
Inflammation
the immune response to tissue damage.
5 signs: redness, swelling, heat, pain, and loss of
function.
Redness – caused by lots of red blood cells (RBC) in area, with
dilated vessels/capillaries
Heat – caused by blood transporting heat to the area, along with a
high metabolic reaction
rate as energy is used to fight the infection
Swelling – caused by excess interstitial fluid when the capillaries
become ‘leaky’ at the
infection site.
Pain – caused by pressure of swelling and heat on the sensory nerve
endings.
Loss of function – caused by the swelling which stiffens the area and
the pain which makes
the individual resist moving the area.
The goals of Inflammatory Response are:
1) to isolate the area and prevent further damage or
infection;
2) perform a temporary repair; and
3) initiate permanent repair.
What is a MAST cell?
Where are mast cells located?
Review Connective Tissues -
specialized cells.
What is their function?
Histamine promotes inflammation - it CAUSES the
inflammatory response. When the collagen/reticular fibers in a tissue
are damaged - the attached mast cells secrete histamine and heparin.
The histamine promotes the inflammatory response, while heparin helps
keep any RBCs and blood that might be in the interstitial spaces from
clotting.
Inflammation can be caused by:
abrasion
scratching
toxins/chemicals (wasp sting, mosquito saliva, etc)
Pathogens - in this case the inflammation is called an
INFECTION
These conditions cause 'damage' to the
collagen/reticular fibers - which is 'sensed' by the mast cells. The
mast cells release Histamine, which promotes the inflammatory response.
A mosquito bites you, and injects saliva containing a
digestive enzymes and anti-coagulant into the bite. The digestive
enzymes and anti-coagulant (and bite) damage the collagen that connects
your skin cells together. A mast cell senses the damage and releases
histamine --> inflammation. The goal of this LOCAL inflammatory
response is to 'denature' the foreign enzymes and anti-coagulant and
prevent the mosquito from using you as a grocery store. BUT -
You 'scratch' the bite with causes more damage to the collagen in the
area - more histamine is released, more inflammation, and you scratch
more - which causes more tissue damage/stimulation and more histamine
release - which results in MORE damage... and so on.....
Why do you take anti-histamines?
To STOP the inflammatory response!
So, if you can avoid 'scratching' that mosquito/ chigger bite, or that
rash, poison ivy, etc, you can help stop the inflammatory response. This
will allow the inflammatory response to DISAPPEAR, and your tissues will
return to normal, more quickly.
DescribeTissue Repair:
the replacement of dead cells with live, functional cells -
cells that have the same function as the original cell/tissue.
The goal of tissue repair is to MAINTAIN FUNCTIONAL
tissues!
Mitosis is the cellular reproduction process (review
Chap 3, cell reproduction) by which an existing cell (with a specific
function) reproduces itself to form 2 (two) cells that are genetically
identical and have the same function. I.e. the existing cell
produces two cells that are anatomically and physiologically identical!
What is the cellular reproduction process that performs
tissue repair?
What is the other cellular reproduction process that creates the sex cells
Describe Tissue Repair – it
is the replacement of dead cells with live cells that have the same shape
and function as the original cell
How do Tissues change with age?
- Less efficient tissue repair
Cancer is a common problem.
75% of cancers exposure to chemical and other environmental
factors.
- decreased ability to repair more fragile connective tissue
- have altered chemical composition
- are less efficient - remember, each tissue has a specific function - as
we age, the tissues
are less efficient at performing that function
Changes can be caused by:
hormonal changes
changes in lifestyle
inadequate levels of activity (sedentary or bedridden
lifestyle)
improper nutrition
What is a common problem with aging
and tissue repair?
What causes 75% of cancers?
How does aging affect repair of connective tissues?
How does aging affect the ability of a tissue to perform its specific
function?
How does this affect the ability to maintain homeostasis?
List some causes of tissue changes.
LAB
Use the illustrations in your book to study these.
Know them in a GENERAL way.
Primary Tissue Types
What is the unique characteristic of
each of these that allows you to classify a tissue as one
or the other?
Epithelial Tissue
Connective Tissue
Muscle Tissue
Neural Tissue
Epithelial Cell Shapes
Squamous
Cuboidal
ColumnurBe able to draw the different shapes
Epithelial Types
Be able to recognize these types of epithelial tissues.
Simple Epithelium - single layer of cells
Simple Squamous Epithelia - flat, plate-like cells
Simple Cuboidal Epithelia - cube shape
Simple Columnar Epithelia - columnar
Stratified Epithelium - multiple layers of cells
Pseudostratified Epithelia - all cells are attached to the basement
membrane and
to the surface.
Stratified Squamous Epithelia - multiple layers of flat plate-like cells.
Mucus membranes
and integumentary system. Be able to draw an epithelium and label the components.
Connective Tissues
Connective Tissue Proper
Loose Connective Tissue
Areolar Loose CT
Adipose Tissue
Dense Connective Tissue
Tendons
Ligaments
Fluid Connective Tissues
Blood
Lymph
Supporting Connective Tissues
Cartilage
Hyaline Cartilage
Elastic Cartilage
Fibrocartilage
Bone
Compact bone
Spongy bone (cancellous bone)
Make a table of the different CT’s. List the:
matrix,
specialized cells,
extracellular proteins, and
major functions of each type.
Connective Tissue Fibers
Collagen Fibers
Elastic Fibers
Reticular Fibers
Know the major function of each extracellular protein
fiber.
Know an example of the CT in which each fiber is found and
the function of that CT.
What is regular dense connective tissue?
What is irregular dense connective tissue?
Give an example of where each is found and the function of
the CT in that location.
Muscle Tissue
Skeletal Muscle Tissue
Cardiac Muscle Tissue
Smooth Muscle Tissue
Be able to compare and contrast the three muscle types (make
a table!).
Neural Tissue
Draw and label a neuron.
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