1. Unit 12: Regulation and Reproduction
Assignment 2: The Nervous and Endocrine Systems
Lesson 3: The Endocrine System

2. Question 1
Name the type of neuron which takes sensory information to the brain or spinal cord.

3. Sensory Neuron

4. What is another name for the interneurons?
Question 2
What is another name for the interneurons?

5. Relay neurons

6. What are the junctions between neurons called?
Question 3
What are the junctions between neurons called?

7. Synapses

8. Question 4
At a Synapse, the electrical impulse is transmitted by chemicals called …

9. Neurotransmitters

10. Name a neurotransmitter…
Question 5
Name a neurotransmitter…

11. Acetylcholine, Noradrenaline, GABA, serotonin, dopamine…

12. What is the scientific name for a nerve impulse?
Question 6
What is the scientific name for a nerve impulse?

13. Action Potential

14. What is the voltage of a resting potential in a nerve cell?
Question 7
What is the voltage of a resting potential in a nerve cell?

15. -70mV

16. Question 8
Which two ions are responsible for maintaining a resting potential in a neuron?

17. Sodium and Potassium

18. Question 9
Which ion is responsible for initiating an action potential?

19. Sodium

20. end

21. What happens when…
…somebody asks you the time? Try to describe each step and how signals are transmitted from one neuron to the other.

22. Lesson Objectives
To know the names and locations and functions of the main endocrine glands.
Know how the two main types of hormone have effects on target cells.
To know how blood glucose concentration is regulated by adrenal hormones.

23. What is a Hormone?
An exocrine gland secretes fluids ______ the body. An example would be ____________.
An endocrine gland secretes fluids into _________.
A hormone is a chemical _______________ which can bring about changes in target ________.

24. What is a Hormone?
An exocrine gland secretes fluids outside the body. An example would be saliva/sweat.
An endocrine gland secretes fluids into the blood.
A hormone is a chemical messenger which can bring about changes in target cells/tissues/organs.

25. How do hormones work? Autocrine:
A cell produces a hormone which acts on that same cell.
Paracrine:
A cell produces a hormone which acts on the surrounding or nearby cells
Endocrine:
A gland produces a hormone which travels in the blood and acts on target cells / tissues / organs
For your assignment we want to know about ENDOCRINE function

26. Endocrine glands
Label the gland and list the hormones made at each one :

28. The two main types of Hormone:
1. Steroid Hormones:
e.g. Sex Hormones
These are lipid soluble so can easily diffuse across cell membranes to enter target cells.
2. Peptide Hormones
e.g. Adrenaline, insulin, glucagon.
These are not lipid soluble so have to bind to receptors on the cell surface. This leads to the activation of a second messenger.

29. Endocrine Action 1: Lipid Soluble (Steroid) Hormones E.g. Oestrogen
These hormones can easily pass through the plasma membrane to gain entry to a cell and have its action on the cell. (i.e. bring about a change)
They usually enter the nucleus to have
their effects.

30. Endocrine action 2: Non – lipid soluble hormones E.g. Peptide hormones
Cannot directly enter the cell as they are not lipid soluble.
So, these hormones bind to a receptor on the surface of the cell.
This receptor triggers the release of a ‘second messenger’ inside the cell.
This second messenger brings about a change in the cell.

31. Second Messengers

32. Glucoregulation
Research and make notes on how the following hormones regulate blood sugar level:
Insulin
Glucagon
During your research, try to find out what the following words mean:
Glycogenolysis
Gluconeogenesis
Glycogenesis
You have 20 minutes…

33. Feedback:

34. Fight or Flight:
What do you understand about the fight or flight response in mammals?
Write a few sentences to describe what you think it is…

35. Fight or Flight, an introduction: