The endocrine system
And the many hormones and glands
Crystals of progesterone under microscope
Pheromones
• Pheromones are environmental
signals that act at a distance between
individual organisms.
• Ex: ants, female silkworks, dogs
Hormones
• A hormone is an organic chemical
produced by one set of cells that
affects a different set.
• A hormone travels through the
circulatory system to its target organ.
• Cells respond to a hormone depending
on their receptors; they combine in a
lock-and-key manner.
Types of Glands
• Exocrine glands – glands that have
ducts leading to the target. Ex: Sweat
and salivary glands.
• Endocrine glands – glands that do not
have ducts leading to the target. The
hormone is carried by way of the
circulatory system to the target.
Action of Hormones
Peptide hormones (double
messenger system)
• never enter a cell so they bind to a receptor protein in
plasma membrane
• See p. 375 in Bio12 Animation on cd
• a. Peptide hormone binds to receptor protein; relay
system leads to conversion of ATP to cyclic AMP.
• b. Cyclic AMP (cAMP) is made from ATP; it has one
phosphate group attached to adenosine at two
locations.
• c. Peptide hormones are the first messenger; cAMP
and calcium are often the second messenger.
• d. cAMP sets an enzyme cascade in motion.
• e. Activated enzymes can be used repeatedly,
resulting in a thousand-fold response.
Steroid hormones (single
messenger system)
• are smaller and have the ability to cross cell
membranes.
• See p.374 in Bio12 animation on cd
• a. Steroid hormones are lipids.
• b. Inside a nucleus, hormones such as
estrogen and progesterone bind to a specific
receptor.
• c. Hormone-receptor complex binds to DNA
resulting in activation of genes that produce
enzymes.
• http://www.accreteil.fr/biotechnologies/doc_steroidesignal.htm
The
glands
• Animation
hypothalamus
and pituitary
on Bio12 cd
2 control mechanisms
a) Negative feedback
2 Control mechanisms
• Contrary actions of hormones can
control hormonal regulation.
• 1. Effect of insulin is offset by
production of glucagon by pancreas.
• 2. Thyroid lowers blood calcium level
but the parathyroids raise blood
calcium level.
Hormone project: Description
• You are going to teach the rest of the class about
a gland and its hormones.
• You will have to:
• A) have a picture of the gland and its location in
the body
• B) hormones secreted by that gland, their target
cells and their effects
• C) regulated by…
• D) explain diseases due to hyper and/or hypo
secretion of the hormone
Hormone project: Format
• You can present the information using:
–
–
–
–
PowerPoint presentation
Poster
Video (library, bio12cd)
If you make a song or a poem, to help us
understand, you will get extra points
Hormone project: Evaluation
• /10 Information accurate (picture of gland (1),
hormones(1), target cells(2), effects(2),
regulation(2), diseases(2))
• /5 Well explained, audience can understand
(voice, speed, vocabulary…)
• /5 Interactive
• /5 Creativity
• /25 TOTAL
• /2 Bonus: Song or poem
The list of glands and subjects
•
•
Hypothalamus HALEY
Pituitary gland: the master gland
– Anterior pituitary gland (3 persons) FRED, LYNN, KRISTINE
– Posterior pituitary gland Pancreas : you must explain diabetes (2 persons)
ESI, LUKE
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•
•
•
•
•
•
•
•
Adrenal glands (2 persons) VICTOR CONNOR
Thyroid gland AVERY
Parathyroid gland JESSICA
Testis TYREL, ANDREW
Ovaries : you must explain the menstrual cycle (2persons) A’S
Pineal gland REBBECCA
Thymus NICK
Adjustments to stress ADAM
Chemically enhanced sports performance JOSH