Isotonic solution should be your answerrrr
Answer:
Antibiotic resistance can evolved in bacterial population in the following ways:
Explanation:
- In response to constant exposure to antibiotics some members of a bacterial population develop some beneficial mutations in some essential genes that gives them survival advantage in terms of food and space over the sensitive bacterial strains and hence they are capable of out-competing the sensitive bacteria.
- This happens due to the process of Natural Selection.
- These genes are called antibiotic resistance genes and bacteria usually carry them on plasmids in form of cassettes where genes resistant to multiple drugs are incorporated. These plasmids are called the MDR or Multi-Drug Resistance Plasmids.
- These resistant plasmids can be easily transferred among bacterial populations by conjugation, transformation or transduction or direct plasmid transfer.
- The resistant genes encode for proteins that render the drug ineffective by promoting their efflux from the cells, preventing their entry into the cell, chemically modifying them such that they become non-functional or altering the target site of the drug.
Answer:
Instable behavior.
Explanation:
The checkpoints currently behaving instable in sally cancer cells because mutants show genetic instability so this instability is the cause of cancer disease. Two checkpoints are sensitive to DNA damage, one occur before mitosis cell division and the other occur before replication of DNA. So damage occur in these two check points leads to instable behavior of cancer cells.
Answer:
The correct answer will be option-B.
Explanation:
Sertoli cells are the large somatic cells present in the testis which helps in the formation of spermatozoa. The Sertoli cells create a suitable environment for the production and maturation of the sperms as they produce certain molecules which nourishes the sperms.
The Sertoli cells act as a barrier between the testis and blood and secrete enzymes like inhibin. They eliminate the apoptotic germ cells and also produce seminiferous fluid to nourish the sperm. They do not play any role in primary spermatocytes.
Thus, Option-B is the correct answer.
Answer:
Animal cells and plant cells