Module 3- topic 3-4: Peripheral Nervous System and Hormones Flashcards
Sensory receptors
Monitor changes in and out of human body
Transmits information back to CNS
Mechanoreceptors
Detect mechanical stimuli
Thermoreceptors
Detect temperature changes
Photoreceptors
Respond to light
Chemoreceptors
Respond to chemicals
Nocireceptors
Detect harmful stimuli and elicit pain response
Receptor potential
Produced by stimuli and I turn causes action potential to travel along afferent fibres
Peripheral nerve fibres
Bundled together to produce peripheral nerve
Endoneurium
Immediately surrounds each nerve fibre
Perineurium
Collects nerve fibres in small bundles called fascicles
Fascicles
Bundles of nerve fibres wrapped in perineurium
epineurium
Collects fascicles with blood vessels to produce peripheral nerve
Spinal reflex
Somatic nerves involved in involuntary automated response
Autonomic nervous system
Maintains homeostasis because sympathetic and parasympathetic send opposing efferent signals to target organs
Impulse pathway of autonomic nervous system
A chain of 2 neutrons plus a junction site
Gangalion
Junction site
Pre ganglionic nerve body
Within CNS
Post ganglionic nerve body
Within a ganglion within pns
Sympathetic ganglia
Close to spinal cord
Parasympathetic ganglia
Within effector organs
Efferent signals in ANS motor neurons
Travel far slower than somatic motor neurons
Effect lasts much longer
Parasympathetic pathway
Releases acetylcholine at both ganglionic and effector synapse
Sympathetic pathway
Releases acetylcholine at ganglionic synapse but releases norepinephrine at effector synapse
Endocrine system
Control and integration of organ systems
Produces and secretes hormones
Hormones
Bond to target tissue and change their metabolism
Endocrine glands
Do not have secretory ducts, release products directly into blood stream
Effects of endocrine system
Much slower than nervous system but are maintained for longer periods of time
Pituitary gland - location
Located at base of brain
Pituitary gland - makeup
Posterior pituary
Anterior pituitary
Posterior pituitary
Extension of hypothalamus
Stores hormones produced by hypothalamus
Anterior pituitary
Derived from epithelial cells
Hormone secreting glandular tissue
How hypothalamus regulates release of hormones
Interconnecting network of blood vessels
Posterior pituitary- hormones
Oxytocin
Antidiuretic hormone
Oxytocin
Stimulates uterine contraction and milk ejection
Antidiuretic hormone (ADH)
Stimulates kidneys to reabsorb water from urine and return to bloodstream
Anterior pituitary- hormones
Human growth hormone Thyroid stimulating hormone Adrenocorticotropic hormone Prolactin Follicle stimulating hormone Luteinizing hormone
Human growth hormone (hGH)
Promotes growth
Increased levels of hGH
Gigantism
Decreased levels of hGH
Dwarfism
Thyroid stimulating hormone (TSH)
Stimulates hormone production by thyroid gland
Adrenocorticotropic hormone (ACTH)
Stimulates hormone production from adrenal glands
Prolactin
Promotes milk production
Follicle stimulating hormone (FSH) and Luteinizing hormone (LH)
Regulate male and female reproductive systems
Thyroid gland - location
Front of neck near Adam’s apple
Thyroid gland - makeup
Composed of numerous follicles lines by single layer of epithelial cells
Thyroid hormones
Thyroid hormone
Calcitonin
Thyroid hormone
Effects metabolism
Calcitonin
Produced by parafollicular cells
Lowers calcium levels
Promotes bone formation by inhibiting osteoclasts
Parathyroid glands - location
4 pea shaped glands at rear of thyroid gland
Parathyroid hormone
Maintains calcium homeostasis
Ways that PTH increases calcium
Activates reabsorption of bone matrix
Increases calcium absorption of small intestine
Increases calcium reabsorption of kidney
Too much pth
Cause oestoclasts to break down large areas of bone to make cysts
Too little pth
Decreases levels of calcium in blood
Adrenal gland - location
Small Pyramid shaped organs at top each kidney
Hormones in adrenal glands
Aldosterone
Cortisol
Sex hormones
Aldosterone
Increases blood pressure by increasing Na+ reabsorption
Formed in zona glomerulosa
Cortisol
Increases metabolism
Decreases inflammatory and immune response
Sex hormones
Onset of puberty
Adrenal medulla
Contains chromatin cells
chromatin cells
Secrete catecholamines
- epinephrine
- norepinephrine
Catecholamine function
Increase: heart rate Blood pressure Metabolism Oxygen uptake
proprioceptors
detect muscle contraction and joint movement
auditory receptors
in ear
otoliths
stones in ear
detects and maintains balance
movement tells brain where head it
olfactory receptors
in the nose
Gustatory receptors
taste buds