Question

Most intracellular receptors are what type of protein?

	a.	enzymes
	b.	neurotransmitters
	c.	steroids
	d.	transcription factors
	e.	DNA

Answer 1

Ans:

c. Steroids

Explanation: Receptors are the protein or glycoprotein that binds to the signaling ligands. There are two types of receptor based on location- intracellular receptors and cell surface receptors. Intracellular receptors are present in the cytosol or nucleus. Most intracellular receptors are steroid hormone (like glucocorticoids) receptors. Extracellular steroid hormone binds to the intracellular steroid receptors in the cytosol and controls the activities of responsive genes. The other type of intracellular receptors present in nucleus are the receptors for vitamin D3 and thyroid hormone. The cell surface receptors binds to the cell surface receptor proteins. Three cell surface receptors are G-protein coupled receptors, ion channel gated receptors and enzyme linked receptors. Neurotransmitters are mainly G-protein coupled cell surface receptors and enzymes are involved in enzyme-linked cell surface receptors. Transcription factors are the protein involved in eukaryotic transcription and DNA is the polymer of nucleotides that stored genetic information.