Answer:
CD40L
Explanation:
The CD40 ligand (CD40L) protein is a transmembrane glycoprotein which is expressed on activated T cells and belongs to the tumor necrosis factor (TNF) superfamily. The hyper IgM syndrome is caused by mutations in the CD40L gene, where the defective protein can no longer bind CD40 on antigen-presenting cells. The X-linked Hyper IgM syndrome is characterized by abnormal levels of immunoglobulins, i.e., low levels of IgG and IgA, and increased/normal levels of IgM. Because CD40L gene is located on the X chromosome, this disorder is observed much more frequently in males than in females.
Answer:
A.The hole in the ozone layer
Explanation:
• Montreal protocol is an international treaty that was signed to control the use of substances that are resulting in the depletion of the ozone hole.
This treaty was signed in the year 1987 and became effective form 1989.
• Since the time that this treaty has come into force, there has been a significant improvement in the ozone hole that was observed over Antarctic as it's size has decreased.
• This improvement has been possible because the treaty helped to phase out chemicals such as chlorofluorocarbons, carbon tetrachloride, etc. that are responsible for ozone hole depletion.
Answer:
yes
Explanation:
that is the answer I think so.
Answer: A Microtubules
Explanation: The cytoskeleton is composed of at last three different types of fibers: microtubules, microfilaments, and intermediate filaments. These fibers are distinguished by their size with microtubules being the thickest and microfilaments being the thinnest.
