Answer:
They're made of more than one cell
Explanation:
Cell,tissues ,Organs and Organ Systems. After tissues, organs are the next level of organization of the human body. An organ is a structure that consists of two or more types of tissues that work together to do the same job. Examples of human organs include the brain, heart, lungs, skin, and kidneys
Answer:
air
Explanation: without air you can cant even live
Answer:
they are Na+, K+ and Ca2+ ion channels.
Explanation:
Ionotropic acetylcholine receptors are also called nicotinic acetylcholine receptors because beside acetylcholine (Ch) they respond to nicotine. These receptors are primary receptors in muscle for motor nerve-muscle communication that controls muscle contraction.
Two molecules of ACh are required for receptor to open. Since the receptors are linked to ion channels, the channels open. Opening of the channel allows positively charged ions to move across it: sodium enters the cell and potassium exits.
Answer: Denaturing
Explanation: Enzymes are made of amino acids that are linked by bonds, amongst those bonds are hydrogen bonds that are very weak. High temperatures and low pH(acidity) breaks those bonds changing the molecular conformation of the enzymes. That way they denature and loss the ability to perform their functions. High temperatures and acidity alter the structure of their active site preventing the substrate from binding to them. While high temperatures denatures enzymes, low temperature renders them inactive.