What are hormones?
Chemical messages that travel from glands, through the blood, to different organs.
Where are hormones released from?
The endocrine glands.
What do hormones bind to?
Receptors.
Adrenocorticotropic hormone
Stimulates the adrenal gland.
Pituitary gland (anterior)
Thyroid-stimulating hormone
Stimulates the thyroid gland to produce T3 and T4.
Pituitary gland (anterior)
Follicle stimulating hormone (FSH)
Stimulates ovulation and formation of corpus luteum.
Pituitary gland (anterior)
Luteinising hormone (LH)
Controls the development of follicles in the ovaries.
Pituitary gland (anterior)
Prolactin
Stimulates milk production.
Pituitary gland (anterior)
Growth Hormone
Regulates tissue repair and promotes growth.
Pituitary gland (anterior)
Anti-diuretic hormone (ADH)
Directly acts on kidneys and blood vessels, controlling the amount of water content in the blood which helps maintain homeostasis via osmoregulation.
Pituitary gland (posterior)
Oxytocin
Causes contactions during parturition.
Pituitary gland (posterior)
Insulin
Lowers blood glucose.
Pancreas
Glucagon
Raises blood glucose.
Pancreas
Somatostatin
Prevents large fluctuations in blood glucose levels.
Pancreas
Adrenaline (Epinephrine)
Triggers 'fight or flight' response.
Adrenal gland (medulla)
Cortisol
A 'stress hormone' which gives the body an energy boost by controlling the way the body processes nutrients.
Adrenal gland (cortex)
Aldosterone
Contributes to osmoregulation. Regulates the balance of salt/water in the blood by instructing the kidney to remove or release certain salts from the blood.
Adrenal gland (cortex)
Triiodothyronine (T3) and Thyroxine (T4)
Influence growth, and control metabolism speed.
Thyroid
Calcitonin
Moderates calcium blood levels. Stimulates the absorption of calcium by the bones.
Thyroid
Parathyroid hormone
Regulates calcium blood levels. Raises calcium levels if they are too low.
Parathyroid
Oestrogen and Progesterone
Develop secondary sex characteristics (mammary glands), prepare the uterus for pregnancy, maintains the pregnancy and stops the animal coming into heat during gestation.
Ovaries
Testosterone
Promotes sperm production, develops secondary sex characteristics (facial hair in human males), and is involved in male sexual development and behaviour (aggression, territorial behaviour).
Testes
Types of hormone stimuli
Nerve impulses (adrenaline), stimulating hormone (thyroid-stimulating hormone), chemicals in the blood (glucose), and feedback loops (oestrogen preventing further secretion of FSH).
What is a circulating hormone?
Circulating hormones are hormones which travel through the body. (Histamines, produced by cells when they detect foreign material and are part of the immune response).
What is a locally acting hormone?
Locally acting hormones effect one area/organ. (Insulin produced by the pancreas only acts on the liver).