Cyclopropane is a highly strained molecule because the conformations of the cycloalkanes are influenced by the torsional, angle strain, and steric strain. Cycloalkanes, which comprises more than three atoms of carbons are not flat molecules, they are puckered.
The three and four-membered ring components exhibit angle strain and minimize the internal bond angles. The angle strain is generated when the bond angles deviate from the optimum tetrahedral angle, that is, 109.5 degree.
Torsional strain is a resultant of eclipsing interactions, and steric strain is attained when the atoms are forced too close to each other.
Answer:
The correct order would be:
A vaccine introduces a weakened flu virus into the body.
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The immune system identifies antigens on the weakened flu virus.
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Antibodies are produced, which bind to the weakened flu virus and signal immune cells to destroy it.
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The actual flu virus enters the body, and lymphocytes recognize the antigens.
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Antibodies are quickly produced and allow the body to fight off the infection.
Vaccination or immunization is the process which helps in developing the immunity (adaptive) against a particular pathogen or microorganism.
It includes the administration of antigen, weakened or heat-killed microorganism (such as flu virus) into the patients body. Body's immune system produces naive B and T cells to eliminate the antigen.
This encounter enables the immune system to produce memory B and T cells against that particular pathogen.
In future, whenever the same antigen enters the body, the immune system gets activated quickly due to the presence of memory cells. It enables the body to produce more effective secondary response against the pathogen.
No matter what the cell type, prokaryotic or eukaryotic, plant or animal, the cell membrane forms a protective barrier between the exterior environment and the interior of the cell.
Answer:
B
Explanation:
The folds contain ribosomes attached to the membrane. The more the folds the more the surface area to which more ribosomes can attach. The ribosomes are organelles responsible for the manufacture of protein in cells. Thereafter, the proteins are properly folded by the mediation of chaperones in the lumen of the RER.
Answer:
Option A, Start the reaction by absorbing light energy
Explanation:
Chlorophyll is a green color pigment in plant that helps in entrapping sunlight. Being green in color, it absorbs the blue and red light and reflects the green light. The molecules of chlorophyll gains energy from sunlight and then jumps to higher energy levels by the process known as photo excitation. These excited molecules get ionized to further initiate the process of photosynthesis.
Hence, option A is correct.
