two Barr bodies
A Barr body is the inactivated X chromosome when in a case like this, there is more than one X chromosome for only one place. In this case, because there are two more X chromosomes than it would be normal, it will result in two Barr bodies. So, the number of Barr bodies will be <span>is always the total number of X chromosomes minus one.</span>
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.
Vectorborne transmission of an infectious organism occurs via <u>animals or insects. </u>
Vectors are living organisms that can transfer an infectious disease from infected animals to humans. These species are known as arthropods. It includes mosquitoes, ticks, triatomine bugs, sandflies, etc.
There are two types of vectors; Biological and mechanical.
Biological vectors such as mosquitos transmit the disease by biting the host body. Mechanical vectors on the other hand cause infectious disease just by physical contact.
Arthropod vectors are cold-blooded. The diseases that are transmitted by them are known as vector-borne diseases. Malaria and Dengue are examples of vector-borne diseases.
If you need to learn more about vector-borne diseases, click here
brainly.com/question/1621516?referrer=searchResults
#SPJ4
Lamarck called his theory, the theory of Acquired Characteristics. Lamarck's Theory of Inheritance of Acquired Characteristics has been disproved. This was done in two major ways. The first is by experiment. We have seen through many real examples and observations that changes that occur in an animal during life are not passed on to the animal's offspring.
