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Topic 11 Animal Physiology
11.1 Antibody production and
vaccination
• Immune system attempts to eradicate pathogens.
• Pathogen is any agent of disease.
• Most are viruses and bacteria, but some ar
protists, fungi and worms.
• Immune system id’s cells as not self bases on
membrane proteins.
• Antigen is used for any protein ideentified as
• Not self.
• Example:
• Blood proteins determine your blood type.
• ABO blood type is based on 2 proteins called the
A protein and the B protein.
• Rh type bases on a protein called the Rh protein.
• Type A blood has the A protein, type B has the B
protein, type AB has both proteins and type O
doesn’t have either protein.
• If you have the Rh protein, you are Rh +, if you
don’t have it you are Rh –
Steps of Immune response
• Leucocytes are white blood cells.
• One type of leucocyte is the B lymphocyte
(plasma cell).
• There are many different types of B
lymphocytes.
• Each type of B lymphocyte can produce a
specific antibody against a specific antigen.
• We don’t have enough of each kind to be
effective.
• Only 1% of blood cells are leucocytes so each
type of lymphocyte is found in small numbers.
• There is a method of communicating which B
lymphocyte is needed and making copies or
clones to attack an invading pathogen.
• Step one – (Non-specific) First type of
leucocyte to encounter pathogen is a
macrophage (phagocyte).
• Step 2- if it identifies it as non self, it engulfs it
by phagocytosis and starts to digest it.
• Step 3 – pieces of the pathogen are displayed
on the cell membrane of the macrophage,
called antigen presentation.
• Step 4 – (Specific) lymphocytes called helper T
cells recognize the antigen being presented
and become activated.
• Step 5 – Activated helper T cells activate
specific B cell to make antibodies.
• Macrophage presents antigen…helper T
lymphocytes become activated…B
lymphocytes become activated.
• Activated b cell begins mitosis (cloning) and
make two types of cells, plasma cells that
make antibodies, and memory cells.
True Immunity
• Everything mentioned so far is part of a
primary infection. This takes time to get high
levels of the specific b cells needed so you get
sick, then hopefully the immune response
wins.
• A second infection of the same pathogen
causes the memory cells to respond quickly,
preventing you from getting sick.
Antibodies
• Antibodies are proteins produced by (plasma cell)
b lymphocytes.
• Very similar to each other.
• Y shaped molecules with the ends of the forks
different, and called the binding sites.
• Antibodies work in different ways.
• Bind to pathogen, marking it for destruction by
cells.
• Use their two binding sites to bind two antigens
together, creating clumps of pathogens.
Vaccines
• A vaccine can expose your immune system to
a pathogen so you get a primary response,
without you getting sick.
• Usually it’s the actual pathogen but killed first.
• Following this primary response, it the live
pathogen enters your body, the secondary
response is so quick, you have few or no
symptoms.
Active vs Passive Immunity
• Active immunity is when an organism
produces antibodies that gives it immunity.
• Passive immunity is when one organism
produces antibodies that benefits another
organism. Ex: Newborns have passive
immunity from antibodies in mothers milk
(colostrum), antivenom given after snake
bites.
Diseases in more than 1 species.
• The viruses HIV/AIDS, Ebola, SARS, and H1N1
have all originated in one species, then
transitioned to another, specifically humans.
• Does not happen often.
• More common for Bacteria and fungi to do
this. Ex: TB, salmonella, ring worm
Monoclonal Antibodies
• The primary immune response by an organism
is called a polyclonal response because the
pathogen has many proteins on its surface
that cause responses by several different bcells.
• Researchers can create a specific antibody in
the lab called a monoclonal antibody.
Procedure for Monoclonal Antibody
Production
• Inject a specific antigen into a mouse.
• Wait while mouse has primary response.
• Remove spleen (ouch) to get blood cells including
the b-cells that are producing the antibodies.
• Keep the b-cells alive by fusing them with
cancerous myeloma cells, when they are grown
together, some will fuse and become hybridoma
cells that have characteristics of both cells. They
make the antibody and live a long time
• Put all the cells into an environment that will kill
all the b-cells and all the myeloma cells and only
allow the hybridoma cells to live.
• Individual hybridoma cells are grown and their
particular antibody is tested. (Called an ELISA
test).
• Test identifies which cells are making the
antibody you are looking for, and these cells live
so long they are referred to as being immortal.
Use of Monoclonal Antibodies
• Pregnancy test. If pregnant, embryo makes
hormone called human chorionic
gonadotropin (HCG)
• Hybridoma cells can be created to make
antibodies against this protein.
• Antibodies are chemically bonded to an
enzyme that causes a color change if antibody
encounters HCG
Allergies and histamine
• Non-pathogenic substance (allergen) cause a
particular b cell to make antibodies called IgE.
• The IgE antibodies attach to another white
blood cell called a mast cell.
• When the allergen is encountered a second
time, The antibody attaches to the allergen
which causes the mast cell to release
histamine.
11.2 Movement
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Endoskeletons and Exoskeletons
Provide support
Provide attachment points for muscles.
Endoskeletons are made out of bones.
Exoskeletons are made of chitin
Both can act as levers to increase ability of
movement.
• Asian weaver ants can lift 100x their own weight.
• Fleas can jump 150x their own body length.
Muscles in antagonistic pairs
• One end of a muscle is attached to something
that doesn’t move, the other end to
something that can move.
• One muscle moves something in one
direction, a different muscle moves it the
other way.
• Bicep/tricep example
• Bicep attached to radius, tricep to ulna
Synovial joint
• Bone to bone joint with a capsule filled with
synovial fluid.
• Hinge so limited direction of movement.
• The ends of the bones are covered with
cartilage for cushioning.
• Ex: elbow, knee
• Shoulder and hip are ball-and socket, which
have more directional movement.
Vocabulary from elbow
• Cartilage – reduces friction and cushions
• Synovial fluid – lubricates to reduce friction
and provides nutrients to cartilage cells
• Joint capsule – surrounds joint, forms synovial
cavity, unites connecting bones.
• Tendon – attach muscle to bone
• Ligament – attach bone to bone
• Bicep – contracts to bend arm
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Tricep – contracts to straighten arm
Humerus – lever that anchors bicep and tricep
Radius – lever for bicep
Ulna – lever
Muscle fiber
• A muscle fiber is a muscle cell.
• There are 3 types of muscle, smooth, cardiac
and skeletal.
• Skeletal muscle cells are highly modified for
contraction, so their cell structure is different
than most cells.
• Muscle cells are called muscle fibers because
of their elongated shape.
• Muscle cells are multi nucleated and there cell
membranes are called sarcolemma.
• The sarcolemma has projections that
penetrate into the cell called T tubules.
• The cytoplasm is called sarcoplasm and has
many vacuoles to store glycogen.
• It also has a hemoglobin type molecule called
myoglobin to store oxygen for emergencies.
Myofibrils
• Made of many contracting units called
sarcomeres.
• Each sarcomere extends from Z line to Z line.
• Sarcomeres give skeletal muscle its other
name, striated muscle.
• Muscle tissue can contract because each
sarcomere cam shorten.
• Made from actin and myosin fibers.
• Actin and myosin are proteins, with myosin
being thicker than actin.
• Myosin cant get shorter but the two actin
protein fibers on each end of the myosin move
towards each other. The Z lines get closer to
each other.
Sliding filament theory
• Motor neuron carries action potential to final
synapse between neuron and muscle,
neuromuscular junction.
• Neurotransmitter acetylcholine released into
synapse between terminal end buttons and
sarcolemma.
• Acetylcholine binds to receptors on
sarcolemma.
• Sarcolemma ion channels open and N+ ions
move through the membrane.
• Action potential moves through t tubules
causing release of Ca2+ ions into the
sarcoplasm.
• Myosin heads attach to actin
• Myosin heads flex toward center of
sarcomere.
• Sarcomere shortens, ATP binds to myosin
heads causing them to detach from actin.
Troponin & Tropomyosin
• When a muscle is not contracting, the binding
sites on the actin are covered by the protein
tropomyosin.
• Tropomyosin has the protein troponin attached
to it at regular intervals.
• Troponin has the binding sites for the Ca2+ ions.
• When the ions show up, they bind to the
troponin causing the tropomyosins to uncover
the myosin binding sites.