The immunoglobulin light chain does not have a D segment. In humans, there are two different possible light chain proteins, termed kappa and lambda. Assume that there are 35 V segments and 5 J segments in the human kappa light chain region, and there are 30 V segments and 4 J segments in the human lambda light chain region. How many possible light chain genes can be created from these different segments, simply due to combinatorial diversity

295  

Explanation:

Antibodies (also known as immunoglobulins) are immune system-related proteins that circulate in the bloodstream in order to recognize pathogenic harmful substances (antigens) and neutralize them. An antibody consists of two immunoglobulin heavy chains and two immunoglobulin light chains. There are two types of immunoglobulin light chains: 1-the kappa (κ) light chain, which is encoded by the immunoglobulin κ locus; and 2-the lambda (λ) light chain, which is encoded by the immunoglobulin λ locus. The immunoglobulin light chain is a multidomain protein composed of two domains: 1- the N-terminal variable (V) domain and 2-the C-terminal constant (C) domain. V(D)J recombination is a type of somatic rearrangement process by which T and B cells can assemble different gene segments, which are referred to as variable (V), diversity (D) and joining (J) gene segments. In the question above the number of possible genomic recombination events between immunoglobulin gene segments can be calculated as >> (5 x 35) + (4 x 30) = 295.

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.