1. Topic 11 Animal Physiology

2. 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.

3. 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 –

4. 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.

5. 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).

6. 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.

7. 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.

8. 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.

9. 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.

10. 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.

11. 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.

12. 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

13. 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 b-cells.
Researchers can create a specific antibody in the lab called a monoclonal antibody.

14. 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

15. 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.

16. 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

17. 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.

18. 11.2 Movement 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.

19. 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

20. 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.

21. 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

22. Tricep – contracts to straighten arm
Humerus – lever that anchors bicep and tricep
Radius – lever for bicep
Ulna – lever

23. 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.

24. 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.

25. 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.

26. 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.

27. 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.

28. 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.

30. 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.