Unit 1.4a

Question 1

Why do organisms have signalling molecules?

Answer 1

To signal between their cells

Question 2

What type of proteins have binding sites for specific signalling molecules?

Answer 2

Receptor Molecules / Target Cells

Question 3

How are cellular responses initiated?

Answer 3

By signalling molecules binding and the receptors conformation changing

Question 4

Why do cells produce specific specific signals?

Answer 4

So that only cells with the specific receptors receive the message.

Question 5

Why do signalling molecules have different effects on different target cells?

Answer 5

Due to differences in intracellular signalling molecules and pathways involved.