Download The Endocrine System

The Endocrine System
•The endocrine system secretes
hormones that stimulate growth and
many kinds of reactions, such as activity
levels and moods.
•The major endocrine glands include the
pituitary, the thyroid, the adrenals, the
testes, and the ovaries.
Ovaries & Testes
Ovaries in females and testes in males produce hormones that influence
sexual development and functions.
Both glands produce estrogen, progesterone, and testosterone.
Estrogen and Progesterone
Testosterone
• Estrogen and progesterone are
female sex hormones that regulate
the menstrual cycle.
• Estrogen has psychological as well
as biological effects.
• Low levels of estrogen and
progesterone are found in males.
• Testosterone is the primary male
sex hormone.
• It aids the growth of muscle and
bone.
• It aids development of primary
and secondary sex
characteristics.
• Small amounts are found in
females.
Essential Question: How does the endocrine
system affect the human body?
Basic Vocab
Endocrine System – consists of glands that secrete substances
Hormones – are produced by several different glands and
stimulate growth and many kinds of reactions
Pituitary Gland – responsible for the secretion of many different
hormones that affect various aspects of behavior such as the
growth hormone
Thyroid Gland – produces thyroxin which affects the body’s
metabolism
Adrenal Gland – the outer layer of the adrenal gland, or cortex,
secretes cortical steroids which increase resistance to stress and
promote muscle development
Three Endocrine Glands
The endocrine system consists of glands that secrete
substances called hormones.
The Pituitary Gland
The Thyroid Gland
• It lies just below the
hypothalamus in the middle of
the brain.
• It secretes hormones that include
human growth hormone,
prolactin, and oxytocin.
• Some pituitary hormones
stimulate other endocrine glands
such as the adrenals, thyroid, and
ovaries or testes.
• It produces the hormone
thyroxin.
• Thyroxin affects the body’s
metabolism.
• Too little thyroxin can cause
hypothyroidism and cretinism.
• Too much thyroxin can cause
hyperthyroidism.
Three Endocrine Glands cont.
The Adrenal Glands
• They are located above the kidneys.
• The outer layer, or cortex, secretes cortical steroids.
• Cortical steroids increase resistance to stress, promote
muscle development, and make the liver release stored
sugar to provide energy during emergencies.
• The adrenal glands produce adrenaline and noradrenaline.