C the presence of harmful substances in food
Answer:
a) Acetylcholine is degraded by acetylcholinesterase.
Explanation:
After it binds for its receptor on the plasma membrane of the postsynaptic cell, acetylcholine must be removed in order to prevent repeated stimulation. Acetylcholinesterase is enzyme for the inactivation of acetylcholine, present at all cholinergic synapses. This enzyme hydrolyses acetylcholine and breaks it to the acetate and choline. Choline can be reused for the synthesis of the new acetylcholine molecule so it is taken back into the presynaptic cell.
Answer:
The cell interior would experience higher than normal Na+ concentrations and lower than normal K+ concentrations.
Explanation:
Na+/K+ ATPase exists in two forms: Its phosphorylated form has a high affinity for K+ and low affinity for Na+. ATP hydrolysis and phosphorylation of the Na+/K+ pump favor the release of Na+ outside the cell and binding of K+ ions from the outside of the cell. Dephosphorylation of the pump increases its affinity for Na+ and reduces that for K+ ions resulting in the release of K+ ions inside the cells and binding to the Na+ from the cells.
The presence of ATP analog would not allow the pump to obtain its phosphorylated form. Therefore, Na+ ions would not be released outside the cells. This would increase the Na+ concentration inside the cell above the normal. Similarly, the pump would not be able to pick the K+ from the outside of the cell resulting in reduced cellular K+ concentration below the normal range.
Answer:
Answer is D - cAMP.
Explanation:
cAMP is a small molecule that functions as an intracellular signaling molecule - a second messenger. The first messenger would be the thing that activated the GPCR (e.g. a hormone). The GPCR is a signal transducer (converts extracellular signal to intracellular signal). Once activated, the GPCR activates adenylate cyclase which can be called a signal effector - it is an enzyme that produces cAMP.
I believe heterotrophs are organisms that get their energy by eating other organisms. These organisms are also called predators
