Anti Bodies Flashcards
What are the sections of DNA that don’t code for amino acids called?
Introns
Introns are non-coding sections of genes.
What are the coding sections of DNA that code for amino acids called?
Exons
Exons are the parts of a gene that are expressed.
What is pre-mRNA?
mRNA strands containing both introns and exons
Pre-mRNA is the initial transcript before splicing occurs.
What process removes introns from pre-mRNA?
Splicing
Splicing is a post-transcriptional modification that occurs in the nucleus.
What is alternative splicing?
The removal of certain exons along with introns to form different mRNA strands
This allows for the production of multiple proteins from a single gene.
What is the significance of alternative splicing?
More than one amino acid sequence and more than one protein can be produced from one gene
This increases the diversity of proteins that can be generated.
Fill in the blank: During transcription, both _______ and exons are copied into mRNA.
introns
Both types of sequences are included in the initial mRNA transcript.
In the context of antibody production, what happens to exons that code for anchoring the antibody to the B cell membrane?
They are removed from the pre-mRNA to produce the heavy chain for the secreted antibody
This selective removal enables the production of different forms of antibodies.
True or False: Exons are always included in the final mRNA after splicing.
False
Some exons may also be removed during alternative splicing.
What are plasma cells?
Clones of B cells that secrete antibodies specific to an antigen
Plasma cells are also called B effector cells.
What do plasma cells secrete into the blood?
Loads of antibodies specific to the antigen
What forms when antibodies bind to antigens on pathogens?
Antigen-antibody complexes
What are antibodies made of?
Four polypeptide chains: two heavy chains and two light chains
What is the function of the variable regions of antibodies?
Form the antigen binding sites with a shape complementary to a particular antigen
What is the role of the hinge region in antibodies?
Allows flexibility when the antibody binds to the antigen
How do constant regions function in antibodies?
Allow binding to receptors on immune system cells like phagocytes
What type of bond holds the polypeptide chains of antibodies together?
Disulfide bridges
How do antibodies help to clear infections? List one method.
Agglutinating pathogens
Antibodies bind to two pathogens at the same time, clumping them together for phagocytosis.
What is one way antibodies neutralize toxins?
By binding to toxins produced by pathogens, preventing them from affecting human cells
How do antibodies prevent pathogens from binding to human cells?
By binding to the antigens on pathogens and blocking cell surface receptors
What are the two forms of antibodies?
Membrane-bound and secreted
What is a key difference between membrane-bound and secreted antibodies?
Membrane-bound antibodies have an extra section of protein to anchor them to the B cell membrane
What is the process of copying a gene into mRNA called?
Transcription
Where does transcription take place?
In the nucleus
What can happen to mRNA before it is translated into protein?
It can be modified to create more than one protein from the heavy chain gene
