Grade 12 -Summary -Table of Homeostasis

HOMEOSTASIS
ASPECT GLUCOSE CO2 H2 O SALT TEMPERATURE




Stimulus Glucose level: CO2 levels in the blood Water levels Sodium ions in blood Temperature
1.rises increase 1. Rises 1. Increase 1.rises
2.drops 2. Drops 2.decreases 2.drops




Receptors Islets of Langerhans Chemoreceptors in Osmoreceptors in Afferent + Efferent 1.Hot receptors
1.beta cells secrete carotid artery detect hypothalamus are arterioles 2.cold receptors
insulin carbonic acid in the stimulated, message is
2.alpha cells secrete blood sent to pituitary gland
glucagon


Control centre Pancreas Medulla Oblongata Pituitary gland Adrenal gland Hypothalamus




Reaction Hormones Medulla oblongata ADH is secreted: Aldosterone 1. blood vessels
(hormone/impulse) 1.insulin increase heartbeat and 1.less secreted 1.less aldosterone near skin dilate,
2.glucagon breathing rate via nerve 2.more secreted secreted more blood sent to
Released impulse 2.more aldosterone skin surface, more
secreted sweat produced,
more heat lost to
environment, more
blood sent to sweat
glands
2.blood vessels
near skin constrict,
less blood sent to