Transcript Chapter 14 & 13- Respiration and Immunity

Respiration & Immunity
Chs 14 & 13
Announcements
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Tentative outline:
Nov 23- (Today)- Respiration and Immunity
Nov 30- Digestion & Nutrition
Dec 2- Reproduction & Genetics
Dec 7- DNA and Biotechnology
Dec 9- Evolution
Dec 14- Ecology & Review
Dec 16- Final
Outline
• Respiration
– The Lungs & gas exchange
– The throat
• Immunity
– Innate immunity vs. adaptive immunity
– T lymphocytes and B lymphocytes
– Primary vs. secondary adaptive immunity
– Lab: Finish old labs & STD activity
Respiration
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Gas exchange & Circulation
Structures of the respiratory system
Other structures of the respiratory system
Disorders of the respiratory system
The Respiratory System
• In the respiratory system, oxygen and carbon
dioxide are exchanged across a moist body
surface
• Pressure changes within the lungs cause
breathing
• Blood transports gases between the lungs and
the cells
• Breathing is controlled primarily by respiratory
centers in the brain
• Respiratory disorders have many causes
The Respiratory System
• The function of the respiratory system is to
provide the body with essential oxygen and
dispose of carbon dioxide
The Respiratory System
Breathing moves air
in and out of the lungs.
External respiration
is the exchange of
oxygen and carbon
dioxide between the
lungs and the blood.
Gas transport
moves oxygen and
carbon dioxide
between the lungs
and the body tissues.
Internal respiration is
the exchange of oxygen
and carbon dioxide
between blood and the
body tissues.
Oxygen
transport
Lungs
Gas diffusion
Carbon
dioxide
transport
Gas diffusion
Tissue
Figure 14.1
The Respiratory System
UPPER RESPIRATORY
SYSTEM
• Filters, warms, and
moistens air
Sinuses
• Cavities in skull
• Lighten head
• Warm and moisten
air
Nasal cavity
• Produces mucus
• Filters, warms, and
moistens air
• Olfaction
Pharynx
• Passageway for
air and food
RESPIRATORY
MUSCLES
• Cause breathing
Intercostal
muscles
• Move ribs during
breathing
Diaphragm
• Muscle sheet between
chest and abdominal
cavities with a role in
breathing
Figure 14.2 (1 of 2)
The Respiratory System
LOWER RESPIRATORY
SYSTEM
• Exchanges gases
Larynx
• Air passageway
• Prevents food and drink
from entering lower
respiratory system
• Produces voice
Bronchi
• Two branches of
trachea that conduct
air from trachea to
each lung
Bronchioles
• Narrow passageways
to conduct air from
bronchi to alveoli
Epiglottis
• Covers larynx during
swallowing
Lungs
• Structures that contain
alveoli and air
passageways
• Allow exchange of
oxygen and carbon
dioxide between
atmosphere and blood
Trachea
• Connects larynx with
bronchi leading to
each lung
• Conducts air to and
from bronchi
Alveoli
• Microscopic chambers
for gas exchange
Figure 14.2 (2 of 2)
The Respiratory System
• The nose
– Cleans incoming air
– Warms and moistens the air
– Provides for the sense of smell
The Respiratory System
Figure 14.4a
The Respiratory System
• The sinuses
– Lighten the head
– Adjust air quality
• The pharynx
– The space behind the nose and mouth
– Provides a passageway for food and air
The Respiratory System
• The larynx
– An adjustable entrance to the respiratory system
– Controls the position of the epiglottis to prevent
materials from entering the lower respiratory
system
– The source of the voice
The Respiratory System
Epiglottis
Larynx
Upper
trachea
Front view
(a) The epiglottis is open during breathing but covers the
opening to the larynx during swallowing to prevent
food or drink from entering the trachea.
Figure 14.5a
The Respiratory System
Vocal cords
Glottis
Top view of larynx
During quiet breathing, the
vocal cords are near the
sides of the larynx, and the
glottis is open.
Top view of larynx
During speech, the vocal
cords are stretched over the
glottis and vibrate as air
passes through them,
producing the voice.
(b) The vocal cords are the folds of connective tissue above the
opening of the larynx (the glottis) that produce the voice.
Figure 14.5b
The Respiratory System
• The trachea
– Tube that conducts air between the environment
and the lungs
• Heimlich maneuver
– Can be used to dislodge food from the trachea
The Heimlich maneuver is only a last resort
A person who is choking cannot speak
or breathe and needs immediate help.
The Heimlich maneuver is a
procedure intended to force a large
burst of air out of the lungs and
dislodge the object blocking air flow.
Step 1: Stand behind the choking
person with arms around the waist.
Step 2: Make a fist and place the
thumb of the fist beneath the
victim’s rib cage about midway
between the navel (belly button) and
the breastbone.
Figure 14.6 (1 of 2)
The Respiratory System
Step 3: Grasp the fist with your
other hand and deliver a rapid “bear
hug” up and under the rib cage with
the clenched fist. Be careful not to
press on the ribs or the breastbone
because doing so could cause
serious injury.
Blocking
object
Step 4: Repeat until the object
is dislodged.
Figure 14.6 (2 of 2)
The Respiratory System
• The trachea divides into the bronchial tree
which conducts air to each lung
The Respiratory System
Figure 14.7
The Respiratory System
• The alveoli
– Functional units of the respiratory system
– Minute sacs where oxygen diffuses from the air
into the blood
• For alveoli to function properly they are
coated with phospholipid molecules called
surfactant that keep them open
The Respiratory System
Figure 14.8
The Respiratory System
• Carbon dioxide produced by the cells diffuses
from the blood into the alveolar air to be
exhaled
Pressure Changes within the Lungs Cause
Breathing
• Pressure changes within the lungs cause
breathing
Pressure Changes within the Lungs
Cause Breathing
• When the diaphragm
and intercostal muscles
contract, the volume of
the thoracic cavity
increases, causing the
pressure in the lungs to
decrease
Pressure Changes within the Lungs Cause
Breathing
• Inspiration
– Occurs when the pressure in the lungs decreases
Pressure Changes within the Lungs Cause
Breathing
Inhalation
Rib cage
moves up
and out
Air flow
Intercostal
muscles
contract
Diaphragm
contracts
and flattens
The chest cavity increases
in size, and pressure within
the lungs decreases.
Diaphragm
contracts
The lungs expand, and
air moves in.
(a)
Figure 14.9a
Pressure Changes within the Lungs Cause
Breathing
• Expiration
– When the same muscles relax, pressure in the
lungs increase
Pressure Changes within the Lungs Cause
Breathing
Exhalation
Air flow
Rib cage
moves down
and inward
Intercostal
muscles relax
Diaphragm
relaxes and
moves upward
The chest cavity decreases
in size, and pressure
within the lungs increases.
Diaphragm
relaxes
The lungs recoil,
and air moves out.
(b)
Figure 14.9b
Pressure Changes within the Lungs Cause
Breathing
• The volume of air inhaled or exhaled during a
normal breath is called the tidal volume
• The volume of air moved into and out of the
lungs is an indication of health
Pressure Changes within the Lungs Cause
Breathing
6000
Lung Volume (ml)
5000
Inspiratory
reserve
(forced
inhalation)
volume
4000
Total
lung
capacity
Vital
capacity
Tidal volume
3000
2000
Expiratory reserve
(forced exhalation)
volume
1000
Residual
volume
0
Figure 14.10 (1 of 2)
Pressure Changes within the Lungs Cause
Breathing
Tidal volume
(~500 ml)
Amount of air inhaled or exhaled
during an ordinary breath
Inspiratory reserve volume
(~1900–3300 ml)
Amount of air that can be inhaled
in addition to a normal breath
Expiratory reserve volume
(~1000 ml)
Amount of air that can be exhaled
in addition to a normal breath
Vital capacity
(~3400–4800 ml)
Maximum amount of air that can
be inhaled or exhaled in a single
forced breath
Residual volume
(~1100–1200 ml)
Amount of air remaining in the
lungs after maximum exhalation
Total lung capacity
(4500–6000 ml)
Total amount of air in the lungs
after maximal inhalation (vital
capacity + residual volume)
Figure 14.10 (2 of 2)
Blood Transports Gasses between the
Lungs and the Cells
• Most oxygen is carried by the blood where it is
bound to hemoglobin in a molecule called
oxyhemoglobin
Blood Transports Gasses between the
Lungs and the Cells
• The carbon dioxide produced as the cells use
oxygen is removed by the blood in one of
three ways
1. Dissolved in the blood
2. Carried by hemoglobin
3. As a bicarbonate ion
Blood Transports Gasses between the
Lungs and the Cells
Figure 14.11 (1 of 2)
Blood Transports Gasses between the
Lungs and the Cells
Figure 14.11 (2 of 2)
Disorders of the respiratory system
Respiratory Disorders Have Many
Causes
Figure 14.14
Lung Cancer
• Lung Cancer
– Changes in the cells of
the airway linings
• Eventual uncontrolled cell
division forms a tumor
– Often caused by inhaled
carcinogens, including
those found in tobacco
smoke
Cigarette smoke
Figure 14.4b
The Immune System
• Overview
• Innate vs. Adaptive
The Immune system is the body’s
defense system
• Against:
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–
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–
–
–
–
Bacteria
Viruses
Protists
Other living invaders
Toxins
Foreign debris
Cancerous cells
• The immune system is
complex
• Defends against threats
known and unknown
Elements of the Immune system
• Many lines of defense, for
many kinds of threats
• Skin
• Blood
• Thymus
• Spleen
• Lymphatic system
• Mucous membranes
• Bone marrow
Innate vs. Adaptive immunity
Innate Immunity
• Non-specific
• Defends against known
invaders
• Skin, lysozyme
• Pre-existing
• Cannot adapt to changing
threats
Adaptive Immunity
• Mechanisms which fight
specific invaders
• For unknown threats
• Responsive
• Requires time to build
defense (days)
• Cannot anticipate threats
• Remembers previous
threats
Humoral vs. Cell-mediated Immunity
Cell- Mediated Immunity
• Live cells kill invaders
• Innate: Phagocytic cells
(e.g. macrophages,
neutrophils)
• Adaptive: B lymphocytes
and T lymphocytes create
specific responses to unique
invaders
Humoral immunity
• Proteins in blood
(“humors”)
• Innate- complement
system, clotting factors,
cytokines, etc.
• Adaptive: Antibodies
Blood is a mixture of cells and plasma
Human Blood after centrifugation
• ~55% Plasma
• ~45% Red blood cells
• <1% White blood cells and
platelets (“buffy coat”)
Blood plasma
• Water
• Nutrients
• Solutes- Na+, Cl-,
wastes, CO2, etc.
• Contains humoral
immune elements
• Some innate immunity
Hematopoetic stem cells differentiate
into all blood cells
• Pluripotent- able to
become any one of
many cell types
• Includes T cells, B
cells, macrophages,
etc.
Red blood cells carry oxygen and CO2
• Lose nucleus in
development
• Short-lived, no repair
• Packed solid with
hemoglobin
• Membranes designed to
maximize surface area
• Facilitate gas transfer
Platelets assist with blood clotting
• Recruit plasma protein
fibrinogen to a cut
• They release clotting
factors
• Clotting factors convert
fibrinogen to fibrin
• Fibrin net prevents
blood loss
White blood cells come in a great
variety of types
Elements of Innate Immunity
Nonspecific (Innate) Immunity
• First line
– Surface barriers
• Second line
– Cell-mediated immunity- defensive cells
– Humoral Immunity- Defensive proteins
– Inflammation & fever
Nonspecific Surface Barriers work
against multiple threats
Figure 13.2 (1 of 2)
Nonspecific Surface Barriers
Figure 13.2 (2 of 2)
Lysozyme- an innate enzymatic
defense
• Enzyme that cuts
bacterial cell walls
• Also cuts chitin, a
constituent of fungal
cell walls and arthropod
exoskeleton
• Found in mucous, tears,
egg whites
Nonspecific Internal Defenses
• The second line of defense
– Defensive cells
– Defensive proteins
– Inflammation
– Fever
Nonspecific Internal Defenses
• Defensive cells include neutrophils and
macrophages
– They engulf pathogens, damaged tissue, or dead
cells by the process of phagocytosis
Phagocytic white blood cells devour
bacteria
Nonspecific Internal Defenses
Figure 13.3
Nonspecific Internal Defenses
• The body’s non-specific cellular defenses use
two types of defensive proteins
– Complement system
– Interferons
Interferons are nonspecific anti-viral
signalling molecules
Nonspecific Internal Defenses
• Before a virally–infected cell dies, it secretes
small proteins called interferons that
– Attract macrophages and natural killer cells
– Stimulate neighboring cells to make proteins that
prevent the viruses from replicating
Nonspecific Internal Defenses
• The complement system
– A group of proteins that enhance both nonspecific
and specific defense mechanisms by
• Destroying pathogens
• Enhancing phagocytosis
• Stimulating the inflammatory response
Nonspecific Internal Defenses
Figure 13.5 (1 of 3)
Nonspecific Internal Defenses
Figure 13.5 (2 of 3)
Nonspecific Internal Defenses
Figure 13.5 (3 of 3)
Nonspecific Internal Defenses
• Inflammatory response destroys invaders and
helps repair and restore damaged tissue
– Redness
– Heat
– Swelling
– Pain
Nonspecific Internal Defenses
Figure 13.6 (1 of 2)
Nonspecific Internal Defenses
Figure 13.6 (2 of 2)
Nonspecific Internal Defenses
• Fluid leaks from the capillaries
– Causes swelling
• Blood flow increases
– Causes redness and warmth
Nonspecific Internal Defenses
Figure 13.7
The Inflammatory response
Keeping the body safe comes at a cost
• Inflammation
implicated in heart
disease, etc.
• Gum inflammation
linked to heart attacks
The adaptive immune system
The lymphatic system collects lymph
and houses white blood cells in nodes
Adaptive Immunity contains humoral
and cell-mediated components
Adaptive Immunity is learned, and has
memory
Which of the following mobilizes nonspecific
defense system?
• A) active immunity
• B) inflammation
• C) passive immunity
• D) cell-mediated immunity
• E) none of these
Antibodies- the Key component of
humoral adaptive immunity
• Two light chains, two
heavy chains
• Each contains a variable
region and a constant
region
Antigen- anything which can be bound
by an antibody
B Cells- the
source of
antibodies
Clonal
selection
musters
B-cell
defense
forces
against
specific
antigens
Immune cells are the only cells with
different DNA
• VDJ recombination of light
and heavy chains generate
antibody diversity
• Change is permanent
• A form of Russian Roulette
for the cell
• Successful recombination
creates a binding antibodycell survives
• Unsuccessful- cell is
destroyed
• Finding a good cell takes time
Bound antibodies are the mark of
death for invaders
Breast milk contains maternal
antibodies
• Infants have no
acquired immunity
• Mother’s acquired
immunity is transferred
to the baby through
nursing
• Passive immunity
• Is not retained by the
baby
Vaccination gives the body active
immunity
• An antigen sample is
given to a person
• Person’s immune system
mounts a response to the
antigen
• Antigen can be
deactivated/destroyed
virus particles, etc.
• No waiting time for body
to develop 2o immune
response
Antibodies can be used as therapy
• Some growth factors
are overactive in certain
cancers
• Antibody binds to
growth factors, or their
receptors
Polyclonal Antibodies can determine
blood type
• From multiple B cells
• Bind to different
epitopes of an antigen
Monoclonal antibodies
• Obtained from a
single B cell
• Bind to a single
epitope
• A single B cell is
fused to a myeloma
cell
• Myeloma cells are
immortal
Mouse antibodies can be humanized
• Constant regions of
mouse antibody are
gradually replaced with
human sequences
Fluorescent antibodies can be used in
scientific experiments
• Fluorescent molecules
can be linked to
antibodies
• Antibodies show us
where proteins exist in
vivo
Home pregnancy tests utilize
antibodies
• The transfer of antibodies from breast milk to
an infant is an example of __________
immunity.
• A) nonspecific
• B) passive
• C) humoral
• D) active
• E) cell-mediated
T cells are the primary cell-mediated
adaptive immune response
Major Histocompatibility Complex
(MHC or HLA)
• MHCI
Found on all cells, recognized by TC cells
• MHCII
Found on B cells and Macrophages
recognized by TH cells
When presented with antigen, Helper T
cells recruit other immune cells
• The basic function of T cells is to identify and
destroy invaders in our
• A) blood or lymph.
• B) interstitial fluid.
• C) cells.
• D) immune system.
• E) brain.
CD4 on the surface of TH cells is the
site of HIV binding
Any known stage of the HIV life cycle is
a potential point for therapy
Protease inhibitors prevent formation
of HIV capsids
AZT is a nucleoside analog reverse
transcriptase inhibitor
AZT
Thymine
Cytotoxic T cells destroy infected body
cells
In Autoimmune disease, the immune
system attacks the self
Allergies are immune responses to
harmless antigens
• A substance that can elicit an immune
response is called a(n)
• A) complement.
• B) interferon.
• C) histamine.
• D) antibody.
• E) antigen.