A-I Evolution of immunity Flashcards
Where in evolution did Ig, TCR and lymphocytes show up?
Jawed vertebrates
Does bacteria have adaptive immune system?
While they do not antibodies, TCR and such, they do have the CRISPR/Cas system, which integrates viral genome in its CRISPR locus, making it possible for Cas endonuclease to find and cleave if the virus enters again. This could be seen as a form of adaptive immune systen
Where does IgE and IgG come from evolutionary?
IgY
What does intervertebrates have instead of antibodies?
DSCAM
Superinfection exclusion system
Prophages prevent new phages to enter cell.
Phage defense mechanisms (mediated by phage proteins)
Block receptors, prevent phage DNA translocation, block lysozyme.
True or False: Bacteria can achieve immunity against phages by mutating their receptors
True
True or False: Restriction modification systems in bacteria recognize self-DNA.
False; they recognize viral DNA
True or False: CRISPR/Cas9 is described as a type of innate immunity.
Both true and false
True or False: The term “lymphocyte based adaptive immunity” is proposed as a more inclusive term encompassing adaptive immunity in all organisms.
True
True or False: The innate immune system is a relatively recent evolutionary development found only in vertebrates.
False; this is the adaptive immune system
True or False: Pattern recognition receptors (PRRs) on immune cells respond to specific antigens on the surface of pathogens.
True; but there are intercellular PRRs too
True or False: Toll-like receptors (TLR) in invertebrates are significantly different from those found in mammals.
False
True or False: Only jawed vertebrates possess immunoglobulins (Ig), T cell receptors (TCR), and lymphocytes.
True
True or False: IgE and IgG are thought to have evolved from an ancestral immunoglobulin called IgM.
False; it probably evolved from IgY
True or False: Dscam in invertebrates is a molecule with Ig domains that is involved in a specific immune response.
True
True or False: It is definitively known that Dscam represents a form of adaptive immunity in invertebrates with evidence of later selection.
False; there is no selection for it later on
True or False: Variable lymphocyte receptors (VLRs) are found in vertebrates and are similar to immunoglobulins.
False; it is found in invertibrates
