Endocrine SystemEndocrine SystemControl of Our Bodies Control of Our Bodies

HomeostasisHomeostasis

Engage• You will be viewing some video clips

from Sideshow: Alive On The Inside. Within these clips you will see various types of endocrine disorders.

• If you are interested in viewing more endocrine system oddities, you can read the book Freak Show: Presenting Human Oddities for Amusement and Profit by Robert Bogdan.

Explore• Explore 1• Using your text and other resources, you

will familiarize yourself with the endocrine glands and their functions by completing the endocrine system worksheet.

• Explore 2• Role Play: The Rise and Fall of Glucose

regulates

ExplainSection 39-2

by meansof the

by meansof the

by meansof the

by meansof the

by meansof the

by meansof the

Growth Waterbalance Reproduction Metabolism

Calciumand glucose

levels

Responseto stress

The Endocrine System

Pituitary

Ovaries

Testes Thyroid Pancreas Adrenals

Parathyroids

Explain• List 4 types of endocrine glands

and give their function.• What is the overall function of the

endocrine system?• With what other systems does the

endocrine system interact?

Exocrine or Endocrine• Exocrine – release products

(enzymes) into ducts– Ex) Sweat, tears, digestive juices

• Endocrine – directly to bloodstream; NO DUCTS– Ex) Hormones

Endocrine System• Glands – release products to

bloodstream directly.• Horomones – products deliver

messages to body• Target cells – have specific

receptors for specific hormones

HypothalamusThe hypothalamus makes hormones that control the pituitary gland. In addition, it makes hormones that are stored in the pituitary gland.

Pituitary glandThe pituitary gland produces hormones that regulate many of the other endocrine glands.

Parathyroid glandsThese four glands release parathyroid hormone, which regulate the level of calcium in the blood.

ThymusDuring childhood, the thymus releases thymosin, which stimulates Tcell development.

Adrenal glandsThe adrenal glands release epinephrine and nonepinephrine, which help the body deal with stress.

Pineal glandThe pineal gland releases melatonin, which is involved in rhythmic activities, such as daily sleep-wake cycles.

ThyroidThe thyroid produces thyroxine, which regulates metabolism.

PancreasThe pancreas produces insulin and glucagon, which regulate the level of glucose in the blood.

OvaryThe ovaries produce estrogen and progesterone. Estrogen is required for the development of secondary sex characteristics and for the development of eggs. Progesterone prepares the uterus for a fertilized egg.

Testis The testes produce testosterone, which is responsible for sperm production and the development of male secondary sex characteristics

Section 39-1Endocrine Glands

Pituitary Gland• Master gland

– Controls the other endocrine glands

• Growth Hormone (GH)– Too much –

gigantism– Too little –

dwarfism• Antidiuretic (ADH)

– Stimulates kidneys to keep water

Hypothalamus• Part of brain and attached to

pituitary• Controls pituitary secretions

Thyroid

THYROID GLAND• Regulates

– Metabolism and energy balance

Thyroid Hormones• Thyroxine

– Regulates body energy usage• Calcitonin

– One hormones that regulates calcium and phosphate in blood

Questions• What are the two hormones that

the thyroid secretes?• What is the function of thyroxine?• What is the function of calcitonin?

Parathyroid

Calcium RegulationPARAthyroid Glands

• PTH-Parathyroid hormones• Increases calcium, phosphate, and

magnesium absorption in intestines.• Causes bones to release calcium and

phosphate• Causes removal of calcium and

magnesium from urine by kidneys• Increases the making of Vitamin D in body

Negative Feedback Mechanism

• Our body uses feedback mechanism to maintain homeostasis within our body.

• Regulation of calcium is one example of this process.

• Can you think of another one? Hint: Role Play Activity

Questions• PTH cause the small intestine to

absorb more calcium, _____ and _____.

• What does PTH cause the bones to release?

• What do the kidneys do because of PTH?

Adrenal Gland• Releases hormones to deal with

stress

Adrenal Gland Cont.• Cortex

– Produces more than 2 dozen steroid hormones

– corticosteriods• Medulla

– “fight or flight”– Epinephrine and

norepinephrine

Glucose RegulationTwo Ways:1. Eating Regularly2. Hormone Adjustments

Pancreas: Endocrine and Exocrine

• What did the pancreas do in digestion?

Secreted EnzymesPancreas also secretes hormonesEndocrine glands

- ductless organ that releases hormones DIRECTLY into the bloodstream.

Questions• What do exocrine glands secrete?• What do endocrine glands

secrete?

Blood Glucose Level• Pancreatic Hormones regulate blood

sugar level before and after meals.• Islets; clusters of cells in pancreas

– Alphasecrete glucagon – increases sugar

– Beta secrete insulin – decreases sugar

What Happens?

• Between meals Blood glucose lowPancreas secretes

glucagonLiver changes glycogen to glucoseglucose sent to target tissues

• After a meal Blood glucose highPancreas secretes

insulinGlucose goes to the Liver(Glygogen) and goes to Target tissues

Questions• What organ regulates glucose in blood?• When we eat our blood glucose level is

high or low?• In between meals our blood glucose

level is high or low?• When our blood glucose is high the

pancreas secretes ___________.• When our blood glucose is low the

pancreas secretes ___________.• What mechanism allows our body to

control the glucose level in our body?

Diabetes• Diabetes

– High sugar levels in blood– Do not produce enough insulin to

control blood sugar– Some take insulin injections to

regulate

Reproductive Glands• Production of gametes• Secretion of sex hormones• Female – Ovaries - Estrogen• Males – Testes - Testosterone

Elaborate• You will perform various

investigations with plant hormones to better understand human hormones. You will be working with hormones that stimulate and inhibit plant growth.