1. Hormones and Metabolism
Option D5

2. D5.1 State that hormones are chemical messengers secreted by endocrine glands into the blood and transported to specific target cells.
Pituitary
Gland
Pineal
Gland
Thyroid
Gland
Thymus
Adrenal
Gland
Pancreas
Ovary
Testis

3. D5.2 Steroid hormones bind to receptor proteins in the cytoplasm of the target cell to form a receptor-hormone complex.
D5.3 The receptor-hormone complex promotes the transcription of specific genes.

4. D5.4 Peptide hormones bind to receptors in the plasma membrane of the target cell.
D5.5 Binding of hormones to membrane receptors activates a cascade mediated by a second messenger inside the cell.

5. D5.6 The hypothalamus controls hormone secretion by the anterior and posterior lobes of the pituitary gland.

6. D5.7 Hormones secreted by the pituitary control growth, developmental changes, reproduction and homeostasis.

7. D5.7 Hormones secreted by the pituitary control growth, developmental changes, reproduction and homeostasis.

8. D5.7 Hormones secreted by the pituitary control growth, developmental changes, reproduction and homeostasis.

9. D5.a2 Control of milk secretion by oxytocin and prolactin.
Oxytocin and prolactin are two
hormones directly related to lactation.
What stimulates the secretion of milk?
Low estrogen level (as a result of
birthing process) causes prolactin to
stimulate the milk-producing cells of
the breast to begin releasing milk.
High oxytocin level causes contraction
of smooth muscles surrounding the
ducts carrying the milk, which results
in milk ejection.
Production of both oxytocin and
prolactin is increased by stimulation
caused by a suckling infant. This is
controlled by positive feedback.

10. Example 1: control of ADH (vasopressin) secretion by negative feedback.

11. Example 1: control of ADH (vasopressin) secretion by negative feedback.

12. Example 2: regulating temperature by negative feedback.
Click for animation

13. Example 2: regulating temperature by negative feedback.