Endocrine System Flashcards
Exocrine Gland
Secrete their contents through tubes or ducts onto an interior or exterior body surface e.g sweat
Endocrine Gland
(Ductless) glands secrete hormones directly into the blood stream, which delivers to specific target cells or tissues
Hormone
A chemical messenger that is secrete by an endocrine gland, often carried in blood.
Target Organ
Particular organs that a hormone targets
Paracrine
Cells that communicate with other cells in the same tissue by secreting chemicals that diffuse to adjacent cells.
Hypothalamus
Located in the brain
Secretes hormones that regulate the pituitary gland
Pituitary gland
Located in the brain
2 lobes posterior and anterior
Secretes hormones that control the function of the other glands in endocrine system
Anterior Pituitary hormones
- Adrenocorticotrophic hormone
- growth hormone
- luteinising hormone
- follicle stimulating hormone
- prolactin
- thyroid stimulating hormone
Adrenocorticotrophic Hormone
Stimulates adrenal glands to produce hormones
Growth Hormone
Regulates body growth
Luteinising Hormone
Acts on ovaries to stimulate oestrogen production and testes to stimulate testosterone production
Follicle stimulating hormone
Causes maturation of egg and sperm
Prolactin
Produces milk in mammory glands of breasts
Thyroid stimulating hormone
Stimulates the production and release of hormones from thyroid gland
Posterior Pituitary Hormones
Antidiuretic hormone
Oxytocin
Anti diuretic hormone
Increases water reabsorption in the nephron
Oxytocin
Stimulates contractions in childbirth and contraction of the lobules in the breast for lactation
Thyroid Gland
Located in the neck
Produces thyroxine which increases cellular metabolism
Parathyroid Glands
Four small glands at back of thyroid gland
Produces parathyroid hormone which controls calcium metabolism
Pancreas
Has both exocrine and endocrine glands
Releases pancreatic juices into duodenum
Releases insulin and glucagon into bloodstream
Thymus
Located above heart
Produces thymosins
Involved in maturation of white blood cells
Gonads
Ovaries produce oestrogen and progesterone
Testes produce testosterone
Pineal Gland
Located in the brain
Produces melatonin which regulates day/night response
Adrenal Medulla
Adrenal glands are located on top of kidneys, medulla in the middle
Produces adrenaline and noradrenaline
Involved in sympathetic stimulation of the nervous system
Adrenal cortex
Outer layer of adrenal glands
Hypothalamus Partnership
Interprets nerve impulses and converts them into chemical messages that regulate the secretion of hormones from pituitary gland
Hypothalamus Functions
Regulation of pituitary gland
Production of hormones
Regulation of temperature
Regulation of the autonomic nervous system
Regulation of emotions and sexual behaviour
Anterior Lobe
Responds to factors released from the hypothalamus and produces a variety of hormones
Hormones
Chemical messengers secreted by endocrine glands. Can affect cells or organs. Receptorcides required
Hormones affects on cellular activity
Change the permeability of cell membrane
Change the rate of chemical reactions which occur in the cell
Hormones affects on proteins
Change shape and structure of enzyme
Change rate of transcription/translation of proteins
Steroid Hormones
Enter through plasma membrane into cytoplasm
Stimulates or inhibits particular protein synthesis
Fat soluble hormones e.g testosterone and cortisol
Protein/Amine Hormones
Activate specific receptors on the plasma membrane cannot pass through
Secondary messenger diffuses into cell
Protein and amine hormones are water soluble
Inhibit or stimulate particular enzymes
E.g oxytocin and insulin
Diabetes
Diabetes is a disease that affects your body’s ability to produce or use insulin
Diabetes causes
Type 2:
Genetics
Lifestyle
Unhealthy diet
Obesity
Lack of exercise
Type 1: autoimmune response- body’s immune system attacks and destroys insulin producing beta cells in the pancreasDiabetes symptoms
Extreme thirst Frequent urination Blurry vision Extreme hunger Fatigue Unusual weight loss
Diabetes treatment
Aim of treatment is to keep low blood glucose levels as close to normal as possible
People with diabetes need to monitor blood glucose levels regularly
Type 1: treated with insulin replacement through insulin injections, healthy diet and regular exercise
Type 2: lifestyle modification (healthy diet, regular exercise and weight loss) and oral medications to control blood glucose levels
Hyperthyroidism
Hyperthyroidism (sometimes called thyrotoxicosis) occurs when the thyroid gland is overactive.
Hyperthyroidism causes
The most common cause of hyperthyroidism in Australia isGraves’ Disease, anautoimmune conditionwhere the immune system stimulates the thyroid to produce too much hormone.
Hyperthyroidism can also be caused by the thyroid becoming inflamed (thyroiditis) or by nodules inside the thyroid which become hyperactive.
Hyperthyroidism symptoms
Feel overly anxious
Feeling overly tied
Losing weight despite same lifestyle (Graves’ Disease)
Unable to tolerate heat
Bulging Eyes (Graves’ Disease)
Enlarged Thyroid or Goiter (Graves’ Disease)
Hyperthyroidism treatment
Medicine can be used to reduce the amount of hormone produced by thyroid
Radioactive iodine therapy which shrinks the thyroid
Could be removed by surgery this may lead to damage to surrounding nerves and surrounding glands.
Aldosterone
controls sodium levels
Adrenal cortex
Cortisol
involved in stress response
Produced in adrenal cortex
Hypothyroidism
Where the thyroid gland does not produce enough thyroxine
Slows down cell metabolism
Hypothyroidism causes
Autoimmune disease known as hashimotos thyroiditis
Radiation therapy
Hypothyroidism symptoms
Fatigue Weight gain Sensitivity to cold Depression Muscle weakness pain/stiffness in joints Impaired memory
Hypothyroidism treatment
Diagnosed with blood test- symptoms may not occur
Prescribed hormone tablets called levothyroxine
Combination therapy
