Answer: 1). Epinephrine binds to a cell-surface receptor; the activated receptor stimulates production of the second messenger, cAMP.
Explanation: Epinephrine action begins by binding of the hormone to its specific receptor protein in the plasma membrane known as adrenergic receptor. This protein is a member of a large family of receptors called G-protein coupled receptors. The binding of epinephrine to its receptor triggers a conformational change in the receptor that affects its interaction with a Gs protein. The bound receptor triggers the replacement of GDP bound to Gs by GTP, thereby activating Gs protein. Gs is a heterotriemeric protein having an alpha, beta and gamma subunits. The activation of the Gs protein causes the alpha subunit of the protein to dissociate and move to another membrane protein called Adenylyl cyclase and activate it. The activated of adenylyl cyclase catalyzes the formation of cyclic AMP (cAMP).
Vitamin B12 is more difficult to obtain on a vegan diet since Vitamin B12 is mostly found in most meat and dairy products (which vegans cannot consume). Therefore vegans have to incorporate foods with high amounts of Vitamin B12, such as soy products and to talk to their doctor about taking supplements to make sure they are getting enough.
Vitamin B12 deficiency can cause anemia and nervous system injury
Pray this helps you :)
B- Enzymes act as catalysts to speed up chemical reactions
Answer:
Nitrogenous base
Explanation:
Phosphate and deoxyribose create the "backbone" of a DNA molecule.
Think of the molecule as a ladder.
These(deoxyribose and phosphate) are the sides of the latter.
The nitrogenous bases(A,G,C,T) are the rungs of the ladder.
As the arrow points to the "rung" of the ladder, that means it is a nitrogenous base.
The receptor cell picks up info then sends it to the muscle