In IBDP Biology, we may need to be aware of even more different types of hormones that is around the body, for example growth hormones or ADH, let's go!

Growth Hormone 

GH (aka somatotropin) a protein that stimulates cells to enlarge and divide faster

• enhanced the movement of amino acids through cell membranes and increase rate of protein synthesis
• decreases the rate at which cells use carbohydrates and increase the rate at which they use fats
• peaked secretion at night
• hypothalamus secretes GHRH stimulates GH secreting

Prolactin 

• It is a protein and promotes milk production
• High levels of it can disrupt sexual functions
• Prolactin secretion is mostly under inhibitory control by dopamine from the hypothalamus (aka prolactin release inhibiting hormone)
• hypothalamus likely releases more than one prolactin-releasing factor (PRF) 

Oxytocin 

• Causes or strengthen labour contractions during childbirth
• positive feedback example
• controls bleeding after childbirth
• can be used to induce abortion
• also helps with lactation 

ADH  

• small peptide molecule made in hypothalamus released by pituitary gland 
• prevents production of dilute urine; it causes more permeable membrane to soak up more water
• can stimulate contraction of arteries and capillaries

Types of Hormones 

Steroid Hormones

• can freely diffuse across the plasma membrane of cell
• bind to receptor in cytoplasm or nucleus of target cell to make active receptor-hormone complex which move into the nucleus and bind directly to DNA, acts as a transcription for gene expression

Peptide Hormones

• hydrophylic and lipophobic meaning they cant freely cross the plasma membrane
• bind to receptors on surface of cell which typically have internally anchored proteins
• receptor complex activates a series of intracellular molecules which initiate cell activiy 
• process called signal transduction 
• IE: insulin, glucagon, leptin, ADH, oxytocin  

That is all !

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References:

• https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.osmosis.org%2Flearn%2FGrowth_hormone_and_somatostatin&psig=AOvVaw2TSWSNdxDDmWeneHjA-Iv5&ust=1626351290181000&source=images&cd=vfe&ved=0CAoQjRxqFwoTCJD7he_E4vECFQAAAAAdAAAAABAR
• https://www.google.com/url?sa=i&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FOxytocin&psig=AOvVaw0Mayiic-O3d9ojHZTs30jO&ust=1626354142868000&source=images&cd=vfe&ved=0CAoQjRxqFwoTCNDbjbrP4vECFQAAAAAdAAAAABAD
• https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.dreamstime.com%2Fillustration%2Fantidiuretic-hormone.html&psig=AOvVaw3keZaahI3ZuNffNR4_KE0P&ust=1626354214089000&source=images&cd=vfe&ved=0CAoQjRxqFwoTCMCnxdzP4vECFQAAAAAdAAAAABAD

Drafted by Venetia (Biology)