An important part of topsoil is decayed organic matter. <span> It has the highest concentration of </span>organic matter<span> and </span>microorganisms<span> and is where most of the </span>Earth<span>'s </span>biological<span> soil activity occurs. Hope this answers the question. Have a nice day.</span>
Answer: B. Alleles.
A variant form of any given gene is an allele. One of the two alternative forms of any particular gene which is present at the same locus of the chromosome is an allele.
Different forms of an allele determine the phenotypic traits. Most of the multicellular organisms are diploid having two sets of chromosomes, each inherited from one parent. If both the alleles of any gene are same on the particular position of chromosome then it is termed as homozygous and if the alleles of the gene are different, it is called heterozygous.
Answer:
B. Estrogen binds to specific receptors inside many kinds of cells, each of which have different responses to its binding.
Explanation:
Estrogen is a lipid-soluble steroid hormone and binds to its receptors present inside the target cells. Estrogen binds to specific receptors in different types of cells. Binding of estrogen to a specific receptor in a cell would initiate the specific cellular response. Likewise, binding of estrogen to its receptors in some other cell type would generate a different cellular response. For example, binding of estrogen to transcription factors in the cells of mammary glands may stimulate cell division and differentiation to trigger the development of mammary glands at puberty in females.
Explanation:
A varicocele is when veins become enlarged inside your scrotum (the pouch of skin that holds your testicles). These veins are called the pampiniform plexus. Out of one hundred males, ten to fifteen have varicocele. It is like getting a varicose vein in your leg.
Varicoceles are when the pampiniform plexus veins in the scrotum become enlarged. These veins are like varicose veins (twisted, swollen veins, found in the leg.) Varicoceles form during puberty. They can grow larger and you may notice them more over time. Varicoceles are more common on the left side of the scrotum. This is because the male anatomy is not the same on both sides. Varicoceles can exist on both sides at the same time, but this is rare. About 10 to 15 boys out of 100 have a varicocele.