Answer:
a) withheld information from test subjects about their condition
Explanation:
The Tuskegee syphilis study which was carried between 1932-1972 in the Macon County, Alabama on the African-Americans infected from syphilis.
The U.S. Public Health Service started the study promising the infected persons that they will receive the benefits from the studies like a healthy meal, proper antibiotic medication and other benefits.
But the U.S Public Health Service failed to provide the services mainly the medication in which antibiotic penicillin which could treat the disease was not provided to the patient. As a result of this, syphilis continued in their generations also and people and about 100 subjects died.
They were told that they had bad blood which cannot be treated and thus in 1972, this raised a question over this issue related to ethics as to why the penicillin was not provided as well why the person was kept away from the reality.
Thus, Option-A is the correct answer.
DNA is the genetic material, in a double helix shape, used to make proteins. RNA is the single helix molecule that actually turnd DNA instructions into proteins. ATP is the main storage unit of chemical energy in the cell. All this is a basic comparison you should have learned in 9th grade Biology.
Hope I helped!!!!
Answer:
Microglial cells
Explanation:
Microglial cells are one of the various types of neuroglial cells in the central nervous system. Microglial cells are the small cells and have thin slender processes. Many spine-shaped outgrowths come out of these processes. Microglial cells serve as phagocytes of the central nervous system. These cells clean the cellular debris that is generated during the normal development of the nervous system. Microglial cells also perform phagocytosis of microbes and damaged nervous tissue.
Answer: Diffusion, Osmosis and Active Transport
Explanation:
The processes of transport between the cell and the external environment can be grouped into groups: Passive Processes - occur through the plasma membrane, without energy expenditure to the cell, to equalize cell concentration with the external medium. Examples of such processes are diffusion, facilitated diffusion and osmosis. Active processes - occur through the plasma membrane, with energy expenditure, maintaining the concentration difference between the cell and the external environment. For example, sodium-potassium pump. Diffusion In diffusion, particles move from the highest concentration medium to the lowest concentration medium, so that it can be distributed throughout the medium. Therefore diffusion is a process called passive transport. Facilitated Diffusion is the passive transport of substances across the plasma membrane, without wasting cell metabolic energy, allowing the passage of substrates (molecules or ions) from a more concentrated to a less concentrated medium through specific mediation of carrier proteins, enzymes carriers or permeases along the plasma membrane. This process is mainly used to transport carbohydrates, amino acids, vitamins and some ions: sodium, potassium, calcium. Osmosis is the name given to the movement of water between media with different concentrations of solutes separated by a semipermeable membrane. It is an important physicochemical process in cell survival.
The sodium-potassium pump is an example of active transport. Sodium concentration is higher in the extracellular environment while potassium is higher in the intracellular environment. Importantly, the energy required for this change comes from the breakdown of the ATP (adenosine triphosphate) molecule into ADP (adenosine diphosphate) and phosphate. The sodium (Na +) ion in the cytoplasm is pumped out of the cell. In the extracellular medium, the potassium ion (K +) is pumped into the internal medium. If there was no efficient active transport, the concentration of these ions would equal. Thus, the sodium and potassium pump is important as it establishes the difference in electrical charge between the two sides of the membrane that is critical for muscle and nerve cells and facilitates the penetration of amino acids and sugars.
Answer:
The southern hemisphere is tilted towards the Sun at the point of the year.
