Slow process of chemical coordination → communicate information throughout the body via
hormones secreted by endocrine glands (Hormones are generally proteins)
Hormones- organic chemical substances secreted by endocrine glands and transported in the
bloodstream to target organ(s) with a receptor for given hormone.
Endocrine Exocrine
Vascular, ductless directly into bloodstream to Ducts (salivary glands)
target organ
Endocrine Nervous
slow acting, long lasting, via hormones through fast acting, short lasting, via electrical impulses
from endocrine glands from neurons
Negative feedback loop
Controls a change from a set point by correction in opposite direction to maintain homeostasis
Receptor- detects a change from set point
Control centre - activates control mechanism
Effector- responds
Homeostasis- maintain a steady internal environment ( BGL 3.5 to 5.5 mol.litre, 37*C)
Hypersecretion (+)- oversecretion (hyperactive child)
Hyposecretion (-) - undersecretion (hippo underwater)
Adrenal glands - pyramid shape on top of each kidney
Adrenal cortex (outside)→ Aldosterone- ionic balance in tissue fluid (osmoregulation)
Cortisone- anti-inflammatory- increases body's ability to fight stress
Adrenal medulla (middle)→ Adrenaline
- Increases and strengthens heart rate → increases cellular respiration rate
- Increases blood pressure via vasoconstriction in alimentary canal and skin
- Increase rate and depth of breathing (increase oxygen)
- Increase skeletal muscle tone