I believe the correct answer would be actin filaments. These are polmers that are linear with G-actin as subunits that attaches ith myosin heads during the skeletal muscle contraction. They are necessary for cell shape, adhesion and contraction.
I believe it’s D sorry if i’m wrong!
The alternative pathway of complement useful in the early stages of an infection because <u>It's faster than the other complement pathways</u>.
The alternative pathway is one of three complement pathways that opsonize and kill pathogens. This pathway is activated by viruses, fungi, bacteria, immunoglobulin A and forms an important part of the defense mechanism independent of the immune response.
The alternative pathway (AP) is slowly activated spontaneously by hydrolysis of the internal C3 thioester bond [12–14] and further triggered by contact with various proteins, lipids and carbohydrate structures on microorganisms and other foreign surfaces [1, 15].
To learn more about alternate pathway for early stages of infection, here
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The brain releases endorphins while exercising, the release of these endorphins tend to make people happy.
