1.4.1 communication and signalling; coordination

Question 1

how do multicellular organisms signal between cells

Answer 1

using extracellular signalling molecules

Question 2

what are some examples of extracellular signalling molecules

Answer 2

• steroid molecules
• peptide hormones
• neurotransmitters

Question 3

what are receptor molecules of target cells

Answer 3

proteins with a binding site for a specific signal molecule

Question 4

how is a response initiated within a cell

Answer 4

the binding of a signalling molecule to a receptor molecules changes the conformation of the receptor, which initiates the response

Question 5

is it true that different cell types produce specific signals that can only be detected and responded to by cells with the specific receptor

Answer 5

yes

Question 6

why might signalling molecules have different effects on different target cells

Answer 6

because of the differences in the intracellular signalling molecules and pathways that are involved

Question 7

what may different cell types show (in multicellular organisms)

Answer 7

a tissue specific response to the same signal