Endocrine gland - a group of cells that secretes substances into the blood or directly into an organ.
Differ from exocrine glands, endocrine glands have no ducts and secrete products (hormones) directly into blood.
Hormone - a substance produced by cells that helps specific groups of cells to perform specific functions. It is a product of endocrine gland which functions as chemical messengers to stimulate other cells.
Duct – a channel or tube that conveys a substance. It is part of the exocrine glands (such as salivary glands) which makes contact with surface .
Answer:
cellular membranes
Explanation:
Cellular membranes are selectively permeable because they allow only certain molecules to cross into and out of the cell. The phospholipid bilayer is a selectively permeable membrane that surrounds all biological cells. The movement of molecules across the cell membrane bilayer can occur by passive transport (does not require energy) or active transport (requires energy). For example, water molecules pass passively through the cell membrane (passive transport), while other molecules pass through transmembrane proteins against a concentration gradient (active transport).
Answer:
See the answer below.
Explanation:
Antibiotic-producing bacteria are generally known to have a mechanism that enables them to be resistant to their own antibiotics. The mechanism that enables them to be resistant to their own antibiotic depends largely on the mode of action of the antibiotic substance.
Some of the popular mechanisms used by bacteria to counter their own antibiotic substance include a mutation in the target gene, production of enzymes that inactivate the antibiotic compounds, or efflux of the compounds.
<u>In the case of </u><u><em>Streptomyces griseus</em></u><u>, the inactivity of streptomycin has been linked with the production of a phosphatase inhibitor that prevents streptomycin from getting access to the target site. Hence, the organism is not harmed by its own antibiotic.</u>
There are
50 protons in tin
50 electrons in tin
And 69 neutrons
Hope this helps
