(Anatomy and Physiology) Immune System Flashcards
Substances that are _______ to the body must be identified by the ______ ______. It also has to consider what is _______ to the body to achieve this
Foreign
Immune system
Natural
Define:
Antigen
Any foreign molecule that can induce a response to the immune system
What does the expression antigen refer to? What is not considered antigens?
The body’s own molecules
Large molecules within the intestinal tract
True or False:
Small molecules induce an immune response
False, small molecules DO NOT induce an immune response (such as glucose)
What are the bulk of antigens?
Large proteins or polysaccharides
An antigen should not be…
A molecule in the body that occurs naturally (i.e. it must be foreign)
Antigens are also _______, as well as being _____. This __________ gives a specific _____ to the molecule that the ______ ______ can recognize
Complex
Large
Complexity
Shape
Immune system
Why do antigens have complexity that is recognizable by the immune system and don’t occur naturally in the body?
Prevents the immune system of an animal from destroying itself (also why a transplanted organ will be damaged by the immune system)
Large _________ on the cell surface give them a distinct characteristic that the ______ ______ can identify
Molecules
Immune system
True or False:
Closely related individuals on the surface of the cells have identical antigens
True, this makes them ideal donors of organs
What is the determinant of the antigen?
The identification site of the antigen, a small part of the molecule that allows use to recognize the antigen
Describe the determinant of the antigen (2)
Has a particular shape that the body’s immune system may identify
Large and complex molecules may have several
True or False:
The identification for each antigen is not precise
False, the identification for each antigen is VERY precise
Why are large and complex molecules considered to be quite antigenic?
The immune system is greatly stimulated as the molecule may have several antigenic determinants
The body has distributed collections of _____ tissue to quickly detect ________
Lymph
Antigens
Describe:
Tonsils (2)
Collections of lymph tissue within the framework of connective tissue
Located at the back of the pharynx
Lymph vessels originate in the tissues as small ___________ and form larger _____ that discharge fluid back to _____ _____ that are spread throughout the body and eventually back to the ___________
Capillaries
Veins
Lymph nodes
Bloodstream
What is lymph? What does lymph start as?
The fluid that lymph vessels bring
Lymph starts as the cell-forming interstitial fluid
What happens as blood enters the capillaries?
A portion of the water and small molecules are squeezed out of the vessels, the cells are nourished by this fluid
What tends to preserve much of the bloodstream fluid? How?
The blood protein
The protein’s osmotic pressure keeps the water pulled into the body
What will happen in animals that experience conditions in which protein falls to very low levels?
They will produce more tissue fluid
True or False:
Not all the tissue/bloodstream fluid in the body is reabsorbed
True, this blood (then called lymph) is picked up by the lymph vessels
Define:
Lacteals
Lymphs that absorb lipids from the intestinal tract
Every lacteal begins in the small intestine _____. Such lacteals come together in a larger ________ duct that empties into the ______‘_ ___________ ______
Villi
Thoracic
Thorax’s circulatory system