If one amino acid in a protein sequence is changed what could happen

Match each of the four barriers of innate immunity with its mode of action.

serg [7]

The matches are

A. anatomical barrier is matched with 1. secretion of sweat, saliva, and tears.

The epithelium is a physical barrier constituting one of the first defenses against infectious agents. The desquamation of the epidermis thus eliminates bacteria or other infectious agents that have adhered to the surface of the epithelium. In the digestive tract and the respiratory tract, the movement operated by the peristalsis or the eyelashes contribute to the elimination of the infectious agents. The intestinal flora prevents colonization by pathogenic bacteria acting in particular by competition for nutrients. Tears and saliva also help prevent infection of the eyes and mouth, respectively.

B. physiological barrier is matched with 4. changes in pH and temperature.

In addition to this physical (or anatomical) barrier, the acidic pH and low moisture content of the stratum corneum, and the skin temperature below 37 ° C, are detrimental to bacterial growth. Finally, the presence of antimicrobial peptides and lipids make the epidermis a true defender against infection.

C. phagocytic barrier is matched with 3. signaling to macrophages.

Macrophages are cells belonging to white blood cells (leucocytes), which infiltrate tissues. They come from the differentiation of circulating blood leukocytes, monocytes. Monocytes and macrophages are phagocytes and are therefore capable of phagocytosis.

They participate in innate immunity as a non-specific defense, but are able to participate in adaptive immunity via opsonization.

D. inflammatory barrier is matched with 2. secretion of chemicals.

In an inflammatory reaction, blood flow increases at the lesion area. The blood vessels become more permeable thanks to vasodilator chemical substances, which allows the migration of cells from the blood to the tissues (the call is made using chemokines). The first cells arriving at the site of inflammation are often neutrophils, then macrophages arrive and then lymphocytes if there is immune stimulation.

3 0

4 years ago

Please please helppppp!!!!!!

inn [45]

C is the answer to the question

7 0

3 years ago

Read 2 more answers

As part of a long-term elephant study, biologists counted individuals in a population of elephants each spring. In one year, the

Annette [7]

Answer:

I'm not sure about the answer but the answer that I got is 6.14%, I hope this helps :)

4 0

3 years ago

In the Krebs Cycle of cellular respiration, pyruvate is used to make

Nikolay [14]

Answer:

b. carbon dioxide

Explanation:

This metabolic pathway is called the Krebs cycle after the scientist who first discovered it in 1937. The Krebs cycle is further broken down by pyruvic acid, obtained in the glycolysis process. The process proceeds in two stages. The first is the degree of decomposition of the bicarbonate residue.

The Krebs cycle is the main metabolic pathway for the breakdown of organic matter and the production of energy in the form of reduced coenzymes, which will then be incorporated into ATP.

8 0

3 years ago

A DNA fragment is introduced into the lacZ gene of a plasmid, which also contains an ampicillin resistance gene. What is the app

zhenek [66]

Answer: The bacteria transformed with this particular plasmid will form white colonies on the plates containing ampicillin and Xgal.

Explanation: The lacZ gene produces an enzyme called β-galactosidase which is responsible for the breakdown of lactose into glucose and galactose. The lacZ gene is one of the three genes (the other two being lacA and lacY) of the lac operon which is responsible for the transport and mechanism of lactose in E. coli and many other bacteria.

In recombinant DNA technology, when a plasmid is to be used to transform a host cell, such markers are used to help screen the transformed cells from the ones that have not taken up the plasmid. Xgal present in the plates is an artificial substrate which is hydrolyzed by

β-galactosidase into 5-bromo-4-chloro-indoxyl which will dimerize and oxidise into 5,5'-dibromo-4,4'dichloro-indigo. This is a blue pigment which will give blue color to the bacterial cells. Introducing a DNA fragment in this lacZ gene will make it non-functional so it will not be able to produce the enzyme.

Therefore, when a bacterial cell is transformed with a plasmid containing ampicillin resistance gene and a DNA fragment introduced in the lacZ gene and then grown on plates containing ampicillin and Xgal, white colored colonies will appear. The white colonies will show the bacterial cells that have successfully taken up the plasmid with the DNA fragment incorporated in the lacZ gene as this will render the gene non-functional and will not produce β-galactosidase which will breakdown Xgal to give blue colonies. Since the plates contain ampicillin, only the bacterial cells that have been successfully transformed with the plasmid ( the ones that have the DNA fragment and the ones without it) will grow as the ampicillin resistance will give them resistance against ampicillin in the plates. The bacterial cells that have not taken up the plasmid will not be resistant to ampicillin and will not form colonies on the plate.

This is called blue-white screening which is used to identify successfully transformed host cells. A picture of this is given in the attachment, taken from the following website:

https://www.mun.ca/biology/scarr/Blue_&_White_Colonies.html

8 0

3 years ago