Human Biology Task 1 Flashcards
What do hormones affect
all cells in the body
a particular group (target cells)
a particular organ (target organ
Define Hormones
chemicals, secreted by endocrine glands, that are transported throughout the body in the blood.
- change the functioning of cells by changing the type, activities or quantities of proteins produced
Three types of hormones
Protein hormones
- Made of proteins
- E.g. Insulin
Amine hormones
- Made of single amino acids
- E.g. Adrenaline
Steroid hormones
- Made of lipids
- E.g. Cortisol
5 features of water soluble hormone
- Amine(frm singe amino acid) + protein hormones(frm multiple amino acids)
- Hydrophobic – cannot diffuse through membrane. as the phospholipid tails repell it.
- Attach to receptor proteins in the membrane of the target cell.
- Causes secondary messenger substance to diffuse through the cell and activate particular enzyme
- Quick response, short lasting effects
4 Features of lipid soluble hormone
- Steroid hormones(frm cholesterol)
- Diffuses across membrane (hydrophillic) and combines with receptor inside the cell (nucleus or cytoplasm)
- Hormone-receptor complex binds to section of gene activating/inhibiting transcription and protein synthesis (gene expression).
- Slow to have effect, long lasting.
Two types of glands 3,2
Exocrine glands
- secrete hormones into a duct that carries the secretion to the surface/body cavities.
- E.g. Sweat glands, salivary glands.
Endocrine glands
– secrete hormones into extracellular fluid which passes into capillaries to be transported around the body.
Describe hypothalamus?
contains neurosecreotry cells
- releasing/inhibiting factors travel thru blood vessels sent to ant.pit
- secretes oxytocin and ADH to post.pit
- regulates many of the body’s basic functions. E.g. body temperature, water balance, heart rate.
- mainly acts through the pituitary gland
- produces hormones which travels by blood or along nerve fibres to Pituitary gland
PITUITARY GLAND 4
- Vital to normal functioning.
- Known as ‘master gland’ due to the pituitary hormones often regulating activity of other endocrine glands.
- Some hormones made in hypothalamus are secreted by pituitary gland.
- all hormones secreted are protein
Anterior lobe (pituitary) secretes…1,4,4,3,3,5
Actually produces and secretes
Follicle Stimulating Hormone (FSH)
- targets ovaries/testes
- Female: development of follicles
- Male: sperm production
Leutinising Hormone (LH)
- targets ovaries/testes
- Female: triggers ovulation
- Male: secretion of sex hormones
Growth Hormone (GH)
- targets all cells
- Body growth and increase protein synthesis rate
Thyroid Stimulating Hormone (TSH)
- targets thyroid gland
- Production and release of hormones
Adrenocorticotropic Hormone (ACTH)
- targets adrenal cortex
- Production and release of hormones
Prolactin
- targets mammary glands
- Initiate and maintain milk secretion
Posterior Lobe 2,5
Communicates via nervous impulses
Does not produce hormones, only stores and secretes
Oxytocin
- targets Uterus and mammary glands
- Uterine muscle contractions and milk let-down
Antidiuretic Hormone (ADH)
- targets Kidneys
- Fluid retention
Thymus 3
Thymosin(protein)
- T-Lymphocytes
- Influences the maturation of T-lymphocytes
Pancreas 3,3
Glucagon
- targets Liver
- Raises blood sugar by stimulating glycogen breakdown
Insulin
- targets Liver, muscle and fat stores
- Lowers blood sugar by promoting glucose to turn into glycogen
(Protein)
Testes 5
Androgens (e.g. Testosterone)
(Steroid)
- targets Many tissues
- Stimulate sperm production.
- Growth of skeletal muscle.
- Development/maintenance of male sex characteristics
Ovaries 4,4
Oestrogens
- targets Many tissues
- Development of Female Characteristics.
- Regulates the Menstrual cycle
Progesterone
- targets Uterus and Mammary glands
- Regulate menstrual cycle/pregnancy.
- Prepares mammary glands for milk secretion.
(Steroid hormone)
Adrenal Medulla 3,3
Adrenaline
- targets Most cells
- Fight-or-Flight response
Noradrenaline
- targets Most cells
- Similar effects (increases heart rate)
(Amine hormone
- both increase metabolism
Adrenal Cortex 4,3
Cortisol
- targets Liver
-> cells uptake glucode ised for cell rep
->more glucose used to transport cells
- Promote normal metabolism,
- adapt to stress
Aldosterone
- targets Kidney
- Reduce sodium and increase potassium in urine
(Steroid hormone)
Parathyroid 3
Parathyroid Hormone (PTH) (Protein)
- targets Bones and Kidney
- Controls calcium and phosphate levels in blood
Thyroid 4
Thyroxine(Amine)
- targets All cells
- Controls body metabolism by regulating anabolic/catabolic reactions to release energy.
- Maintains body temp.
Pineal 3
Melatonin(Amine)
- targets Hypothalamus
- Regulates sleep patterns
Hormone cascades 4
- Hormones often involved in a chain of event (cascade).
- Hypothalamus secretes releasing (stimulate secretion) or inhibiting factors (slow down secretion)
- Travel anterior pituitary gland via blood and affect hormones secreted there.
- Hormones secreted from APG can stimulate other glands to produce and secrete their own hormones (e.g. ACTH and Cortisol).
ROLE OF LIVER
Converts glucose into glycogen (for storage) and glycogen into glucose (for release into blood)
Type I Diabetes
Insulin-Dependent 2,2,2,2,2,7
Blood Glucose Levels:
- Hyperglycaemia – blood glucose levels rise higher than normal
Onset:
- Early and rapid onset – occurs during childhood
Insulin production?:
- Body does not produce enough insulin
Cause:
- Caused by destruction of Beta cells - autoimmune response
Management/ treatment:
- Requires insulin injections to regulate blood glucose – insulin is now usually administered via automated pump.
Risks if untreated:
Kidney failure
heart attack
stroke
amputations
blindness
nerve damage
Type II Diabetes
Non-Insulin-Dependent 2,2,2,2,4,7
Blood Glucose Levels:
- Hyperglycaemia – blood glucose levels rise higher than normal
Onset:
- Late onset – occurs during adulthood
Insulin production?
- Body does not respond to insulin
Cause:
- Decreased function of insulin receptors – lifestyles factors contribute to this resistance
Management/treatment:
- Non-insulin-dependent
- Controlled by managing diet and lifestyle.
- Medication may also be required but not insulin.
Risks if untreated:
Kidney failure, heart attack, stroke, amputations, blindness, nerve damage
Thyroid Disorders
Hyperthyroidism and Hypothyroidism
Hyperthyroidism 1,4,6,2
Too much thyroid hormones (overactive thyroid)
Cause(s):
- Autoimmune – antibodies imitate TSH
- Too much iodine
- Tumour on the pituitary gland
Symptoms:
- Nervousness/anxiety
- Tremors/muscle weakness
- Fatigue
- Shortness of breathe
- Goitre (enlarged thyroid)
Treatment: medication, radioiodine treatment, surgery
Example: Graves’ disease
Hypothyroidism 1,5,4,2
Not enough thyroid hormones (underactive thyroid)
Cause(s):
- Low iodine in diet (needed to make T3 & T4)
- Autoimmune (destruction of thyroid cells)
- Treatment of hyperthyroidism
- Pituitary dysfunction
Symptoms:
- Goitre (enlarged thyroid)
- Fatigue – tiredness & muscles aches
- Depression
Treatment: hormone replacement using synthetic thyroid hormones
Example: Hashimoto’s disease
Adrenal Disorders 2,2
Hypercortisolism
(Cushing’s syndrome)
Hypocortisolism
Addison disease (Primary Adrenal Insufficiency)
Hypercortisolism 2,2,2
- Too much cortisol – usually due to excessive levels of ACTH from the pituitary gland
- Commonly caused by tumour (pituitary gland) or excessive use of steroid medication (e.g. asthma)
Symptoms:
- weight gain, high blood pressure, mood swings/anxiety/depression, moon face (round, red, full)
Treatment:
- dependent on the cause – reduction in medication, surgery to remove tumour or medication to decrease cortisol production.
Hypocortisolism 6
Insufficient cortisol (sometimes aldosterone too)
- Due to destruction or dysfunction of the adrenal cortex
- Usually caused by autoimmune response
- Gradual onset but progressive - dependent on degree of adrenal failure
- Symptoms: Weight loss, fatigue, dizziness, muscle weakening, hyperpigmentation (darkening of regions of the skin)
- Treated with hormone replacement therapy.
What are the 5 releasing factors of hypothalamus?
- Thyrotropin-releasing hormones(TRH): stimulates the released of TSH and prolactin
- Gonadotropin- releasing hormone (GnRH) : simulates release of FSH AND LH
- Corticotropin releasing hormone (CRH): stimulates the release of adrenocorticotropin hormone (ACTH)
- growth hormone releasing hormone(GHRH): stimulates the release of growth hormone (GH)
- prolactin releasing hormone (PRH): stimulates release of prolactin
What are the 2 inhibiting factors of hypothalamus?
- Growth hormone inhibiting hormone(GHIH) : inhbits the released of GH and TSH
- Prolactin inhibiting hormone(PIH): inhibits the release of prolactin
What is infundibulum
joins the pituitary gland to the hypothalamus
