The statement that best describes the difference between a gene and an allele is that a section of DNA that usually contains the code for a specific protein that determines a specific trait is a gene, while an allele is a section of a gene. The correct option among all the options that are given in the question is the last option or option "D".
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.
D. Focusing
Sound waves reflected in flat surfaces like walls, floors and ceilings results to uneven dispersion of sounds by creating locations with high intensity and another with low intensity. This process is called Focusing and can be undesirable in auditoriums.
<span>The question says,'decomposition of plants and animal matter present in the soil is largely due to soil micro organism. The statement is true. The soil microbes function by decomposing the organic matter in the soil to the forms usable to plants. The humus produce by these microbes is largely responsible for soil fertility. </span>
Human reproduction<span> takes place as internal fertilisation by sexual intercourse. During this </span>process<span>, the male inserts his penis, which needs to be erect, into the female's vagina, and then either partner initiates rhythmic pelvic thrusts until the male ejaculates semen, which contains sperm, into the vaginal canal.</span>