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.
D is the answer because the rest ate observations
Bottom of chain going up....
Deer Mouse, western toad, woodpecker, gray squirrel, Gopher snake, Mule deer, Cooper’s hawk, Cougar
Answer:
The proportions of nucleotides in the newly formed complimentary strand will be:
14% Thymine (T), 33% Adenine (A), 21% Guanine (G), 32% Cytosine (C).
Explanation:
In a double stranded DNA, the nucleotides of one strand binds with nucleotides of another strand through hydrogen bonds.
Adenine binds with thymine by two hydrogen bonds (A=T) and guanine binds with cytosine by three hydrogen bonds (G≡C).
So, the complimentary strand must have
- thymine equal to the amount of adenine in template strand.
- adenine equal to the amount of thymine in template strand.
- guanine equal to the amount of cytosine in template strand.
- cytosine equal to the amount of guanine in template strand.
Answer:
c. False
This statement is incorrect because the DNA of bacteria is circular without histones.
Explanation:
a. True
Some archaea have very specific lipids in their membrane. Differently of the bacterias that have usual lipids in their membranes.
b. True
Archaebacteria do not have peptidoglycans in their cell wall
d. True
Methanogenic archaeobacteria are those that use carbon dioxide and hydrogen to produce methane. They are found in the digestive system of ruminants, sewers and swamps.
