Endocrine system Beatrice Mwachugu (Endocrine Organs (Pancrease (Alpha…
Endocrine system Beatrice Mwachugu
Secretes parathyroid hormone
Parathyroid hormone increases the concentration of Ca2+ in blood
Secretes thyroid hormone which increase basal metabolic rate
Thyroid cells also secrete calcitonin which lowers blood levels of Ca2+by slowing the release of Ca in the blood.
Secretes amino acid based hormones,epinepherine, and norepinephrine into blood to enhance the fight or flight
Secretes lipid based steroid hormones
Has 3 layers
cells arranged in a branching network
Cells are arranged in a parallel cord
Cells arranged in spherical clusters
Secretes melatonin which is a sleep hormone.
Secretes glucagon that signals liver cells to release glucose to raise sugar levels in blood
Secrete Insulin hormone that signals the body to take glucose from blood
Secretes somatostatin that inhibits secretion of insulin and glucagon
Secrete pancreatic polypeptide that inhibits exocrine activity.
Located in the lower neck
Thymic hormes which is a family of peptide molecules
maintain reproductive organs a nd maintain secondary characteristics of females
Signals uterus to prepare for pregancy
Give secondary characteristics of male and maintain male reproductive organs
Classes of Hormones
Amino acid based
Made of amino acids,peptides and proteins and produced by cells that a rough endoplasmic reticulum
Lipid molecules produced by smooth ER
Control of hormone secretion
Controlled by change in nutrient and ions in blood
Controlled by certain hormones which control the secretion of other hormones
Nervous system stimulates endocrine glands to release hormones .
Types of hormones
Thyroid stimulating hormone
Melanocyte stimulating Hormone
For the hormones to cause changes target cells must have receptor.
Hormones act as triggers or stimulators
They travelin blood or body fluids
Hormones travel slowly
Hormones are messanger molecules