Answer:paracrine
Explanation:glands are specialized tissues that secrete specific chemicals substances.these substances may be enzymes,hormones or lubricating fluid.glands secretes their their products through several mechanisms.some involve the use of ducts ,while others do not.
In paracrine secretion,the secretory products reach their target cells by diffusion through the extracellular space or adjacent connective tissue.
Paracrine secretion do not use ducts.
Similar to paracrine is the endocrine ,in which the secretory products goes through the basal lamina ,into the underlying connective tissue and into the vascular syatem.they too do not use ducts
This is easy, the answer is: <span>Ø</span>
Answer:
Please find the detailed explanation of this statement below
Explanation:
Firstly, a repressed gene is a gene whose expression has been inhibited or repressed. The lac operon in E.coli bacteria is a regulatory unit containing structural genes, a single promoter and operator regions. The promoter is the region where the transcription enzyme (RNA polymerase) binds to in order to transcribe the genes in the lac operon. The structural genes in the lac operon can only be expressed in the presence of lactose sugar.
However, in the absence of lactose, LAC REPRESSOR, which is a transcription factor (protein), prevents the binding of RNA polymerase to the PROMOTER region by binding to the OPERATOR region of the lac operon. This inhibits the expression of the lactose genes in the operon.
Note that, the structural genes in the lac operon (lacZ, lacY, lacA) code for proteins that help break down lactose sugar for energy in the E.coli bacteria. Therefore, a bacteria cell with a repressed lac operon will be unable to degrade lactose sugar.
