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.
A pairs with T
C pairs with G
and vice versa so
TTTTTAACG
CCGAAATGT
So Mendel got roughly 75% yellow and 25% green in f2. This means that f1 contains all heterozygous genes, as shown below
Y y
Y YY Yy
y Yy yy
Summary: 75% YY or Yy, 25% yy
Which means that green (y) is a recessive phenotype, while yellow (Y) is a dominant phenotype, since plants with heterozygous genotype Yy express the yellow trait.
The data has to be verifiable by the scientific community.
Mice that are injected with the living R strain survive.
