Explanation:
Pituitary gland: The main endocrine gland. It is a small structure in the head. It is called the master gland because it produces hormones that control other glands and many body functions including growth. The pituitary consists of the anterior and posterior pituitary.
Ans.
Gene regulation or regulation of gene expression involves mechanisms, used by the cells to enhance or reduce the expression of specific genes to make proteins or RNA. Gene regulation occurs at transcriptional level and post-transcriptional level, which involves regulation at translational level or protein level.
Regulation at translational level or protein level is also important as regulation at transcriptional level. Translational regulation controls formation of proteins from mRNA molecules and includes non-coding mRNAs and repressor proteins. It is important for cell growth, differentiation and cellular response to stress and provides an immediate adjustment of gene expression by directly regulating the protein concentration.
Regulation at protein level involves regulation of active protein. It includes regulation by various small molecules, post-translational modifications (such as phosphorylation), and proteolysis. Regulation only at transcriptional level is not sufficient to provide proper gene regulation and leads to various drawbacks, such as Fragile X Syndrome (due to defect in a protein).
Thus, 'gene regulation is important both at transcriptional level and at post-transcriptional level (during translation or protein level).'
For question 3, it would not leak through the whole sandwich because the cell membrane is thick
That is called A. <span>Circular distribution.</span>
